ASM Specialty Handbook: Aluminum and Aluminum Alloys 9780871704962

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ontents Introduction to Aluminum and Aluminum Alloys General Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Alloy and Temper Designation Systems . . . . . . . . . . . . . 18 31 Physical Metallurgy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Recycling Technology . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Selection and Application of Aluminum Alloys Wrought Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Foundry Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Aluminum-Lithium Alloys . . . . . . . . . . . . . . . . . . . . . . . Powder Metallurgy Alloys . . . . . . . . . . . . . . . . . . . . . . . Aluminum-Matrix Composites . . . . . . . . . . . . . . . . . . . Aluminum Coatings . . . . . . . . . . . . . . . . . . . . . . . . . . . .

59 88 121 143 160

180

Fabrication and Finishing of Aluminum Alloys Molten Aluminum Processing and Casting . . . . . . . . . . Forming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Forging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Extrusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Powder Metallurgy Processing . . . . . . . . . . . . . . . . . . . Heat Treating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Machining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

199 231 247 262 275 290 328

Welding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 376 Brazing and Soldering . . . . . . . . . . . . . . . . . . . . . . . . . . . 420 Adhesive Bonding . . . . . . . . . . . . . . . . . . . . . . . . . . . 438 Cleaning. Finishing. and Coating . . . . . . . . . . . . . . . . . . 451

Metallography. Microstructures. and Phase Diagrams Metallographic Practices . . . . . . . . . . . . . . . . . . . . . . . . . 485 Microstructures of Aluminum Alloys . . . . . . . . . . . . . . . 493 Solidification Structures of Aluminum Alloy Ingots . . . 523 Solidification Structures of Aluminum-Silicon Alloy Castings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 532 Phase Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 542

Properties of Aluminum and Aluminum Alloys Corrosion Behavior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 579 Tribological Behavior . . . . . . . . . . . . . . . . . . . . . . . . . . . 623 Properties of Pure Aluminum . . . . . . . . . . . . . . . . . . . . . 639 Properties of Wrought Aluminum Alloys . . . . . . . . . . . . 645 Properties of Cast Aluminum Alloys . . . . . . . . . . . . . . . . 706

Index ...........................................

732

ecialty

0

Aluminum and Aluminum Alloys Edited by J.R. Davis Davis & Associates Prepared under the direction of the ASM International Handbook Committee Scott D. Henry, Manager of Handbook Development Suzanne E. Frueh, Production Manager Randall Boring, Production Coordinator Dawn Levicki, Production Coordinator Laurie Harrision, Editorial Assistant

.

William W. Scott, Jr., Director of Technical Publications

AS

V*

/WERM;T/OICCAL

The Materials Information Society

Copyright 1993 by ASM International@' All rights reserved

No part of this book may be reproduced, stored in a retrieval system, or transmitted,in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the written permission of the copyright owner. First printing, D e c e m b e r 1993 S e c o n d printing, February 1994 Third printing, March 1996 Fourth printing, March 1998

This book is a collective effort involving hundreds of technical specialists.It brings together a wealth of information from worldwide sources to help scientists, engineers, and technicians solve current and longrange problems. Great care is taken in the compilation and production of this Volume, but it should be made clear that NO WARRANTIES,FXPRESS OR IMPLIED, INCLUDING,WITHOUTLLMITATION, WARRANTIES OF MERCHANTABILITYOR FITNESS FOR APARTICULAR PURPOSE, ARE GIVEN IN CONNECTION WITH THIS PUBLICATION. Although this information is believed to be accurate by ASM, ASM cannot guarantee that favorable results will be obtained from the use of this publication alone. This publication is intended for use by persons having technical skill, at their sole discretion and risk. Since the conditions of product or material use are outside of ASM's control, ASM assumes no liability or obligation in connection with any use of this information. No claim of any kind, whether as to products or information in this publication, and whether or not based on negligence, shall be greater in amount than the purchase price of this product or publication in respect of which damages are claimed. THE REMEDY HEREBY PROVIDED SHALL BE THE EXCLUSIVE AND SOLE REMEDY OF BUYER, AND IN NO EVENT SHALLEITHER PARTY BE LlABLE FOR SPECIAL, INDIRECT OR CONSEQUENTIALDAMAGES WHETHER OR NOT CAUSED BY OR RESULTING FROM THE NEGLIGENCE OF SUCH PARTY. As with any material, evaluation of the material under enduse conditions prior to specificationis essential. Therefore, specific testing under actual conditions is recommended. Nothing contained in this book shall be construed as a grant of any right of manufacture, sale, use, or reproduction, in connection with any method, process, apparatus,product, composition,or system, whether or not covered by letters patent, copyright, or trademark, and nothing contained in this book shall be construed as a defense against any alleged infringement of letters patent, copyright, or trademark, or as a defense against liability for such infringement. Comments, criticisms, and suggestions are invited, and should be forwarded to ASM International. Library of Congress Cataloging-in-PublicationData Aluminum and aluminum alloys /edited by J.R. Davis; prepared under the direction of the ASM InternationalHandbook Committee. p. cm. -- (ASM specialty handbook) Includes bibliographicalreferences and index. 1. Aluminum. 2. Aluminum allovs. I. Davis, J.R. (Joseph R.) II. ASM International. Handbook committee. III. Series. TA480.A6A6177 1993 620.1 '86dc20

ISBN 0-87170496-X

ASM International@ Materials Park, OH 440730002 Printed in the United States of America

ii

"CorrosionBehavior" was based on a nucleus artic1e"Corrosion of Aluminum and Aluminum Alloys-published in Volume 13 of ASM Handbook. This nucleus article was significantlyexpanded by the incorporationof material from six additional articles in Volume 13. This supplemental informationdescribes in greater detail such important topics as intergranular corrosion, evaluation of stress-corrosion cracking, hydrogen damage, exfoliation corrosion, and filiform corrosion. Still other articles are based on information blended from different handbooks. For example, the article "Wrought Products" contains information found in four separate Handbooks as well as Aluminum: Properties and Physical Metallurgy, which was also published by ASM. Lastly, when gaps were identified in subject coverage, new material was introduced. Examples include the articles "Adhesive Bonding," "Brazing and Soldering," "Extrusion,"and "Aluminum-Matrix Composites." The ASM Specialty Handbook is yet another example of the wealth of information available in the largerASM Handbook series. During the many months of work on this project, the editor gained an even greater appreciation of the thousands of Handbook contributors from whom material was drawn. Their efforts have resulted in a unparalleled repository of technical information on metals and their alloys that further solidifies ASM International's reputation as "The Materials Information Society."

The "Information Age" has provided the engineer with unprecedentedaccess to technical informationrelating to the processing, properties, and applicationsof engineered materials. We are truly an informationdriven society fueled by voluminous amounts of printed literature, telecommunications, on-line databases, computer software programs, and the soon-to-be-realizedinteractive communicationstechnology. Despite the many advantages affordedby these learning tools, we are also faced at times with an information overload which contrasts sharply with the engineer's demands for quicker and easier access to information.As the technical world becomes increasingly complex, engineers can ill afford to spend days, or even hours, synthesizing information. Recognizing the need for more specialized sources of information, ASM introduces the ASM Specialty Handbook. To better understand this concept, think of the 18 volume ASM Handbook series as the core of a very large database. This database was not designed to be material specific, but rather addressesthe properties,processing, testing, and characterization of a wide variety of metals and alloys. Yet if a horizontal cross section of this database was searched for information describing a specificmaterial or alloy, abundant and valuable data would be found. Such was the case with the present volume, Aluminum and Aluminum Alloys. Once an outline was established and approved, material on aluminum was drawn from the entire ASM Handbook series as well as other complementary publications and rewritten and edited to form one cohesive document. The result is the largest and most comprehensive single source on aluminum and aluminum alloys ever published. The majority of the articles in the ASM Specialty Handbook are based on multiple sources. For example, the article

Joseph R. Davis Davis & Associates Chagrin Falls, Ohio

iii

Welding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 376 Brazing and Soldering ........................... 420 Adhesive Bonding .............................. 438 Cleaning. Finishing. and Coating . . . . . . . . . . . . . . . . . . 451

Introduction to Aluminum and Aluminum Alloys General Introduction ............................. Alloy and Temper Designation Systems . . . . . . . . . . . . . Physical Metallurgy ............................. Recycling Technology ...........................

3 18

31 47

Metallography. Microstructures. and Phase Diagrams Metallographic Practices ......................... 485 Microstructuresof Aluminrlm Alloys . . . . . . . . . . . . . . . 493 Solidification Structures of Aluminum Alloy Ingots . . . 523 Solidification Structures of Aluminum-Silicon AlloyCastings ................................ 532 Phase Diagrams,. ............................... 542

Selection and Application of Aluminum Alloys WroughtProducts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FoundryProducts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Aluminum-LithiumAlloys ....................... Powder Metallurgy Alloys ....................... Aluminum-Matrix Composites . . . . . . . . . . . . . . . . . . . Aluminum Coatings ............................

59 88 121 143 160 180

Properties of Aluminum and Aluminum Alloys Corrosion Behavior ............................. Tribological Behavior ........................... Properties of Pure Aluminum ..................... Properties of Wrought Aluminum Alloys . . . . . . . . . . . . Properties of Cast Aluminum Alloys . . . . . . . . . . . . . . . .

Fabrication and Finishing of Aluminum Alloys Molten Aluminum Processing and Casting . . . . . . . . . . Forming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Forging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Extrusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Powder Metallurgy Processing . . . . . . . . . . . . . . . . . . . Heat Treating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Machining. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

199 231 247 262 275 290 328

Index...........................................

V

579 623 639 645 706 732

uction to Aluminum an Aluminum A General Introduction ....................................................................................

AlloyandTemperDesignationSystems ....... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PhysicalMetallurgy ................................................................................... RecyclingTechnology .................................................................................

3 18 31 47

General ntrod ucti on ALUMINUM, the second most plentiful metallic element on earth, became an economic competitor in engineering applications as recently as the end of the 19th century. It was to become a metal for its time. The emergence of three important industrial developments would, by demanding material characteristics consistent with the unique qualities of aluminum and its alloys, greatly benefit growth in the production and use of the new metal. When the electmlytic reduction of alumina (Al203) dissolved in molten cryolite was independently developed by Charles Hall in Ohio and Paul Heroult in France in 1886, the first intemalcombustion-engine-powered vehicles were appearing, and aluminum would play a role as an automotive material of increasing engineering value. Electrification would require immense quantities of lightweight conductive metal for long-distance transmission and for construction of the towers needed to support the overhead network of cables which deliver electrical energy from sites of power generation. Within a few decades the Wright brothers gave birth to an entirely new industry which grew in partnership with the alumhm industry development of StmctunllY reliable, strOnf5 and fracture-resistant Pa* for airframes, engines, and ultimately, for missile bodies, fuel cells, and satellite components. The aluminum industry’s growth was not limited to these developments. me first commercial applications of aluminum Were nove b items such as mirror frames, house numbers, and sewing trays. cooking utensils were also a major early market. In time, ahminum grew in diversity of applications to the extent that virtually every aspect of modem life would be directly or indirectly affected by its use. \

Aluminum Production All aluminum production is based on the Hd-Heroult process. Alumina refined from bauxite is dissolved in a CIyolite bath with various fluoride salt additions made to control bath temperature, density, resistivity, and alumina solubility. An electrical current is then passed through the bath to electrolyze the dissolved alumina with oxygen forming at and reacting with the carbon anode, and aluminum

collecting as a metal pad at the cathode. The separated metal is periodically removed by siphon or vacuummethods into crucibles, which are then transferred to casting facilities where remelt or fabricating ingots are produced. The major impurities of smelted aluminum are iron and silicon, but zinc, gallium, titanium, and vanadium are typically present as minor contaminants. Internationally, minimum aluminum purity is the primary criterion for defining composition and value. In the United States, a convention for considering the relative concentrations of iron and silicon as the, more i m p o m t criteria has evolved. Reference to grades of unalloyed metal may therefore be by purity alone, for example, 99.70% aluminum, or by the method sanctioned by the Aluminum Association in which standardized Pxxx grades have been established.In the latter case, the digits following the letter P refer to the maximum decimal percentages of silicon and iron, respectively. For example, P1020 is unalloyed smelter-produced metal containing no more than 0.10% Si and no more than 0.20% Fe. PO506 is a grade which contains no more than 0.05%Si and no more than 0.06% Fe. Common P grades range from PO202 to P1535, each of which inc~rpol&% additional impurity limits for control purposes. Refining steps are available to attain much higher levels of purity. Purities of 99.99% are achieved through fractional crystallization or Hoopes cell operation. The latter process is a three-layer electrolytic pxucess which employs molten salt of greater density than pure molten aluminum. Combinations of these purification techniques result in 99.999% purity for highly Specialized applications.

recovery representing 31.2%. Detailed data on U.S. supply of aluminum from 1981to 1991 are given in Table 2. The source of secondary production is m p in all forms, as well as the product of skim and Qoss pmcessing.primary and sewndary production of a l e u m are integralty related and complemmw. M ~ wrought Y and c& composi~ons mnstrucw to reflect tfie impact of controll& elementContaminationthat may accompany ST consumption. A recent trend has been inmased use of scrap in primary and intepted secondaryfabricatingfacilities for various wrought produd, incluhg can sheet. As showninTable 3, reclmation fromaluminum cans increased in 1991to an estimated 893 thousand metric tons, up 1.8% from 1990, accounting for 62.4% Of m shipments.

=

Aluminum Alloys It is convenient to divide aluminum alloys into two major categories: casting compositions and wrought compositions. Afurther differentiation for each category is based on the primary mechanism of property development (see the discussion below on “Heat-Treatable and NonHeat-Treatable ~ l l ~ ~ ~ ” ) . have Cast and wIoughtalloy nomenclatures been developed. me Aluminum Association systemismostwi~elyrecognizedinthe united states. ’Iheir alloy identification system employs different nomenclaturesfor wrought and cast alloys, but divides alloys into families for simplification(see the amcle ,,lloy and Temper Designation Systems” in this Volume for details). For wrought alloys a fourdigit system is us(d to produce a list of wrought c0mposition families as fo11ows:

Prod“dio” statisticS’ w * d thousand ~ u d o n metOf primary aluminum totaled 18,056 ric tons in 1991(‘&ble 1). Over the decade 19811991, world production increased 19.7%, an annual growth rate of 2.0%. The United States m u n t e d for22.Wofthewofid’s 1991production while the E~~~ a m u n i t y accounw for 125%.other EWE)ean countries, including former members of the Union of Soviet S&&t Republics, accounted for 21.0%. The remaining 43.6% includes Asia (11.6%), Canada (lO.l%), South America (9.9%),Oceania (8.5%),and Africa (3.4%). The total U.S. supply in 1991 was 8,02Othousandrnetrictons, withprimaryproduction representing about 51.3% of total supply, impo* accoUnting for 17.4%, and secondary

lm controlled unalloyed @ure> ComPosition used primarily in the electrical and c~emictdindusllies 2xm Alloys in which copper is the principal alloying element, though other elements, notably magnesium, may be specified. 2wr series alloys are widely used in aircraft ~ X X XAlloys in which manganese is the principal alloying element. Used as a genedpurpose alloy for architectural applications and various products

4 / Introduction to Aluminum and Aluminum Alloys

Table 1 World primary aluminum production from 1981 through 1991 Country

1991

1990

1989

1988

1987

1986

1985

1984

1983

1982

1981

Africa

612

616

607

59 1

579

554

513

410

420

500

473

C~eroOn

89 178 175 170

93 179 174 170

92 180 169 166

87 173 161 170

79 179 150 171

84 175 125 170

90 209 49 165

73 170

79 141 174 106

65 134

167

77 140 42 161

North America

5.95 1

5,615

5,585

5,478

4,883

4.392

4.782

5.321

4,444

4,339

5,605

Canada United States

1,830 4,121

1,567 4,048

1.555 4.030

1,534 3,944

1.540 3,343

1,355 3,037

1,282 3,500

1.222 4,099

1,091 3353

1,065 3,274

1,116 4,489

Latin America

1,794

1,783

1,692

1,543

1,486

1,389

1,153

1,048

938

795

788

165 950 51 28 600

166 93 1 68 28 590

1 62

437

153 843 60 2 428

148 757 37 29 41 8

136 549 43 29 3%

134 455 44 29 386

133

890 72 28 540

154 874 68

29 335

138 299 41 43 274

134 256 43 41 314

2,091

2,012

1,995

1,775

1,577

1.488

1,568

1,595

1,390

1,417

1,682

210 860

183 710 375 185 40 35

204 115 39 256

17 1 380 217 33 45 35 1

130 350 213

...

10

10

10

10

2

176 410 260 217 43 227 10 18

177 400 269 199 42 287

2

180 615 265 202 45 41 10 22

178 410 257 219 40 140

...

187 850 423 197 45 35 10 18

172

185 67 32

213 850 433 186 59 34

18

13

18 31 40 106

Egypt Ghana SWthAliiCa

Algentina BI-dzil Mexico Suriname Venezuela Asia

Bahrain China, €?R.(a) India Indonesia Iran Japan Korea, Peop. Rep. K o r q Republic of Taiwan Turkey United ArabImirates European Community FranCe

Germany, Fed. Rep.@) EasternStates Western States GEZX IdY Netherlands

sw

United Kingdom Other Europe

440

10

10 18

10 19

...

401 40

400

190 84

...

13 77 1

...

...

...

...

...

...

...

...

...

56 239

61 174

62 168

57 162

42 155

60 155

54 153

38 155

30 151

15 10 36 149

2,265

2,347

2,361

2,359

2,387

2.35 1

2,283

2,403

2,282

2,340

2583

286 700 20 680 152 218 260 355 294

326 736 21 715 150 232 258 355 290

3 35 734

328 75 3

323 793

322 765

293 745

342 777

361 743

390 723

436 729

145 2 19 279 352 297

151 226 278 323 300

127 233 276 341 294

124 243 266 355 276

125 224 25 1 370 275

136 230 249 38 1 288

136 1% 235 358 253

135 233 367 241

274 262 397 339

3,800

4,098

4,458

4,388

4,349

4,120

4,007

3,927

3.733

3,498

3,415

80 68

89 70

95 67 61 75 82 864 48 265 99 72 2,400 260

93 68 68 76 85 853 48 260 81 73 2,400 244

93 33 61 74 76 726 48 269 78 80 2,300 282

94 32

94 36 57 74 76 713 44 223 82 76 2,000 258

94 34 58 74 75 638 43 208 79 75 1,900

94 33

74 73 743 47 247 84 73 2,200 280

96 32 58 74 80 765 46 244 83 79 2.100 270

220

173

251

146

A& Czechoslovakia(a)(c) GermanD.R.(a)(b) Hungary Iceland Norway Poland(d) Romania Sweden Swiherland U.S.S.R.(a) YugOSlavia

...

...

64 89 833 45 158 97 66 2,000 300

75 88 845 46 168 % 72 2,200 349

93 69 54 75 88 863 48 269 97 71 2,400 331

Oceania

1,543

1,542

1,502

1,414

1,256

1,118

1,092

1,001

697

544

533

Australia New Zealand

1,235 308

1,234 308 18,013

1,244 258

1,150 264 17,548

1,004

882 236

85 1 24 1

15,398

478 219 13,W

38 1 163 13,433

379

15,412

75 8 243 15.705

Total world(a)

lgOS6

18.200

252 16,517

60

60 74 74 634

66 242 83 82

1.800

154 15,079

Note: Values are given in thousands of mehic tons. (a) Estimated by the Bureau of Mmes, U.S. Department of Interior. (b) Geman Democratic Republic and FedRal RepuMic of Gemany combined in 1990. Source: Ref 1. (c) Includes secondary unalloyedingot. (d) Includes primary alloyed ingot.

. 4.m Alloys in which silicon is the principal

alloying element Used in welding rods and brazing sheet 5.m Alloys in which magnesium is the principal alloying element Used in boat hulls, gang-

planks, and other products exposed to marine environments &wr Alloys in which magnesium and silicon are principal alloying elements. Commonly used for architectural extrusions

7xxrAlloysinwhichzincistheprincipalalloying element, but otherelements such as copper, magnesium, chromium, and zirconium may be specified. Used in aircraft structural components and other high-strength applications

General Introduction / 5 Table 2 Total U.S. supply of aluminum from 1981 through 1991 Year 1981 1982 I983 1984 1985 1986 1987 1988 1989 1990

1991

Total supply

Domestk primary

7,061 5,762 6,149 7,235 6,594 6,655 7,035 7,534 7,437 7,863 8,020

4,489 3,274 3,353 4,099 3,500 3,039 3,347 3,945 4,030 4,048 4,121

production

Total 782 823 1,023 1,376 1,332 1,843 1,702 1,467 1,353 1,421 1,398

Imports Primary(a)

645 616 743 882 869 1,349 1,246 1,027 926 962 1,029

Mill pmducts(b)

Dmnestk seeondnry remwry(c)

138 207 281 494 463 494 456 440 427 459 369

1,790 1,666 1,773 1,760 1,762 1,773 1,986 2,122 2,054 2,393 2,501

Note: Values are given in thousands of metric tons. (a) Some imports of starter metal, classified by the Bureau of the Census in 1954-57 as scrap, have been classified as primary metal, as estimated by the De@. of Commerce. (b) Starting in 1970, includes reimports of metal exportedforprocessingandretumedforfurtherp~essing.(c) Domestic secondaly data arerecoverablemetal contentfor estimatedtotalscrapconsumption,as estimated bytheBureau of Mines. Before 1972, totalsupplyincludedsecondiuyrecoveryandanestimated90%~overyfromreportedscrapimports. Beginning in 1972 ~eBureauofMinesrequuedredrepoaing of imported scrap recovery data and these data are included in the domestic recovery figures beginning that year. Source: Ref 1

usually in combination with various annealing procedures for property development. These alloys are referred to as non-heat-treatable or Thousands of metric tons Number(in billions) Percentageof Year ofaluminumcdkted of aluminumcanscdlected(a) aluminumcmsmOected(b) work-hardening alloys. some casting alloys are essentially not heat treatable and are used 1981 46 1 (c) 24.9 53.2 only in as-cast or in thermally modified condi1982 510(c) 28.3 55.5 tions unrelated to solution or precipitation ef1983 519(c) 29.4 52.9 fects. 1984 556(c) 31.9 52.8 33.1 5 1.0 Heat-treatable aluminum alloys a r e 1985 565(d) 33.3 48.7 those that can be hardened (strengthened)by a con1986 559(d) 1987(e) a @ ) 50.5 trolled cycle of heating and cooling. Some alloys, 36.6 1988 683(d) 42.5 54.6 usually m the 2wr, k,and 7 m series, are soh1989 7Wd) 49.4 60.8 tion heat mtabb-they can be strengthened by 1990 877(d) 55.0 63.6 heating and then quenching,or rapid cooling. They 1991 893(d) 56.8 62.4 maybehrtherstrengthenedb y c o l d w o r k h ~ n trolled defonnation& roOm mpelatW2. (a) Calculation based on an Aluminum Associationcan weight survey. (b) Based on Can Manufacturers Institute aluminum bevemge can shipment data. (c) Net receipts, U S . Departmentof Interior Bureau of Mines. (d) Estimated by The Aluminum Associaneincrease of smgthi n d u d by h a mation Statistical and Market Research Committee. (e) Beginning in 1987, used beverage can data include estimate of exponed can ment can be dramatic. For example, in the fullyscrap. Source: Ref 1 annealed 0-temper, aluminum alloy 2024 has an ultimate yield strength of about 186MPa (27 ksi). 4xrx Alloys in which silicon is the principal Heat treatment and cold working followed by 8 m Alloys including tin and some lithium natural aging (3'-3 temper) increases its smngth compositions, characterizing miscellaneous alloying element Sxlcx Alloys in which magnesium is the 2l/2 times, to 483 MPa (70 ksi). compositions 9xrx Reserved for future use principal alloying element As strength is increased by heat-treating, for6zxUnused mability is affected in the other direction: for 7 x . ~Alloys ~ in which zinc is the Principal example, an alloy in the T-3 temper is less forCasting compositions are described by a alloying element, but other alloying &- mable than a fully soft alloy in the o-temper. three-digit system followed by a decimal mentS such as copper and magnesium may value. The decimal .O in all cases pertains to Non-heat-treahble aluminum alloys are be specified casting alloy limits. Decimals . l , and .2 conhardenable by cold working, but not by heat W8xrx Alloys in which tin is the Principal ment. nei,-,i~strengthof&w alloys, us* cem ingot compositions, which after melting in alloying e k ~ e n t and processing should result in chemistries the lm,3 m , 4m, and 5 m series, is providedby 1 conforming to casting specification require- * 9 ~ xUnused the hardening effect of their alloyingelements.Adments. Alloy families for casting compositions ditional strengtheningcan be created by cold wcikare: ing-defonnation which induces strain-hadening, Heat-Treatable and denotedbythe Htempers. Al'oys l n x Controlled unalloyed (pure) composi- Non-Heat-Treatable Cold working can increase strength signifitions, especially for rotor manufacture can*y in non-heat-treatable al1oys. For examp1e, 2xxx Alloys in which copper is the principal Many alloys respond to thermal treatment *e ultimate tensfie strength of '10~ 3003 is inalloying element, but other alloying ele- based on phase solub es. These treatments (16 ksi) in *e ments may be specified include solution heat treatment, quenching, creased from about 'lo *a O-@mFrto200ma(29hi) intheH-18 strain3 n x Alloys in which silicon is the principal and precipitation, or age, hardening. For either alloying element, but the other alloying ele- casting or wrought alloys, such alloys are de- hardened temper. The Ultimate tensile Strength Of ments such as copper and magnesium are scribed as heat treatable. A large number of alloy 3004 is increased fiomabout 179 MPa (26 specified. The 3 n x series comprises nearly other wrought compositions rely instead on ksi) in its 0-temper to about 283 MPa (41 ksi) work hardening through mechanical reduction, in the H-38 temper. 90% of all shaped castings produced

Table 3 Aluminum can reclamation in the U.S. from 1981 through 1990

.

6 / Introduction to Aluminurn and Aluminum Alloys Table 4 Strength ranges within wrought aluminum alloy families Alloy-Temper

’

.

1060-0 1060-HI8 1350-0 1350-819 2219-0 2219-T87 2024-0 2024T35 1 3003-0 3003-HI8 3004-0 3004-H38 5005-0 5005-H38 5052-0 5052-H38 5056-0 5056-H 18 6063-0 6063-T832 6066-0 6066-T6 7050-T73510 7060-T7651 7075-0 7075-T6 7178-0 7178-T6

i

Ultimate tensile strength MPa ksi

69 131 83 186 172 476 186 469 110 200 179 28 3 124 200 193 290 290 434 90 290 152 393 490 552 228 572 228 607

IO 19 12 27 25 69 27 68 16 29 26 41 18 29 28 42 42 63 13 42 22 57 71 80 33 83 33 88

Comments

Alloy 1060-0 is the “softest”al1oy generally available. It is used mainly for sheathing tube in the wire and cable industry. Alloy 1350was developed especially for electrical conductors in both solid and tubular forms. Alloy 2219 is used at eitherelevated or cryogenic temperatures with good welding characteristics. Alloy 2024 is used mainly for structural members in aircraft. It can be spot welded. Note the great increase in strength provided by an appropriate temper. Alloy 3003has good cornsion resistance, formability, and weldability. It is used inchemical equipment, furniture, condensers, heat exchangen. and pressure vessels. The 5 x u series alloys were developed as “marine alloys,” highly resistant to corrosion even in salty environments.

Alloy 6063 is probably the most popular extrusion alloy. It can be heat-treated for strength, is cornsion-resistant, and takes a good surface fmish.

These 7m-series alloys are used for structural parts of aircraft where high strength is required. In the fully-annealed 0-temper their relativelylowerstrengthmaymakeshaping themeasier. Once brought tothe highertempers, however, they are strongerthan carbon steel and nearly as strongas stainless steel.

Source: Ref 2

Table 5 Comparative strength-to-weight ratios for various materials Material

I

7178-T6 7075-T6 2024T361 5056-H 18 6066-T6 Stainless steel (type302) 606 1-T6 3004-H38 Fiberglass (average) 1350-H19 6063-T5 -3003-HI4 Carbon steel (1020) Architect’sbronze 5005-0 3003-0 PVC plastic 1060-0 ,-,ccopper Enameling imn

5picalultimate tensile strength, ksi

88 83 72 63 57 140 45 41 I9 27 27 22 60 60 18 16 7.5 IO 32 38

Density.lWin.3

0.102 0.101 0.101 0.096 0.098 0.290 0.098 0.098 0.05I8 0.0975 0.099 0.099 0.284 0.303 0.098 0.099 0.0504 0.0975 0.322 0.383

Strength-to-weight ratio

863 822 713 65 6 594 48 3 459 418 367 277 273 22 2 21 1 198 184 162 149 103 99 99

Note: 1ksi = 6.89 h4F’~0.1 Ibhn3 = 2.768 g/cm3. Source:Ref 2

Properties Among the most striking characteristics of aluminum is its versatility. The range of physical and mechanical properties that can be de-

velope&from refined high-purity aluminum to the most complex a l l o y e i s remarkable. More than three hundred alloy compositions are commonly recognized, and many additional variations have been developed internationally andin supplier/consumerrelationships. Compo-

sitions for both wrought and cast aluminum alloys are provided in the article “Alloy and Temper Designation Systems” that immediately follows in this Volume. The properties of aluminum that make this metal and its alloys the most economical and attractive for a wide variety of uses are appearance, light weight, fabricability,physical properties, mechanical properties, and corrosion resistance. Density versus Strength. Aluminum has a density of only 2.7 g/cm3, approximately onethird as much as steel (7.83 g/cm3), copper (8.93 g/cm3), or brass (8.53 glcm3). One cubic foot of steel weighs about 4 9 lb; 0 a cubic foot of aluminum, only about 170 lb. Table 4 illustrates the general range of strengths available within each of the major wrought aluminum alloy families. This table demonstrates the important effect that different tempers have on strength in the same alloy. Table 5 compares the strength-to-weight ratios (specific strength) of various aluminum alloys and other materials. Corrosion Resistance. Aluminum resists the kind of progressive oxidization that causes steel to rust away. The exposed surface of aluminum combines with oxygen to form an inert aluminum oxide fdm only a few ten-millionths of an inch thick, which blocks further oxidation. And, unlike iron rust, the aluminumoxide film does not flake off to expose a fresh surface to further oxidation. Scratch t h u g h aluminum’s protective layer and it instantly reseals itself. The thin oxide layer itself clings tightly to the metal and is colorless and transparentin-

General Introduction / 7 visible to the naked eye. The discolorationand flaking of iron and steel rust do not occur on aluminum. Appropriately alloyed and treated, aluminum can resist corrosion by water, salt, and other environmental factors, and by a wide range of other chemical and physical agents. The corrosion characteristicsof aluminum are examined in detail in the article "Corrosion Behavior" in this Volume. Physical Properties. Aluminum surfaces can be highly reflective. Radiant energy, visible light, radiant heat, and electromagnetic waves are efficiently reflected, while anodized and dark anodized surfaces can be reflective or absorbent. The reflectance Of POfished aluminum9Over a broad mge Of wave lengths9leads to its se1ection for a variety Of decorative and functional uses. A1uminum typical1y disp1ays exce11ent e1ectrica1 and therma1 conductivity9 but 'pcific al10ys have been deve1oped with high degrees Of e1ectrica1 resistivity. These a11oys are usefulv for examp1e, in high-torque e1ectric motors*A1uminum is Often se1ectedfor its e1ectrical conductivity* which 's near1y twice that Of copper On an equivalent weight basis. The requirements Of high conductiviQ and mechanical strength can be met by use Of longline* high-voltage* a1uminum stee1-c0red reinforced transmission cable. The thermal conductivityOf a1uminum alloys~about 50 to 60% that Of copper' is advantage0us in heat exchangers, evaporators, e1ectrica11y heated app1iancesand utensi1s7and automotivecy'inder heads and radiators. A1uminum is nonferromagnetic*a propem Of imPOrtance the e1ecaica1 and e1ectronics industries. It is nOnpFOPho*c* Which is important in app1icationsinv01vinginflammab1e Or explosive-mate*alshand1ingOr exposure-A1uminum is a1so non-toxic and is routine1y Used in containers for foods and beverages*It has an attractive appearance in its natura1 fiNsh* which c~ be 'Oft and lustrous Or bright and shiny. It can be virtual1yany "lor Or texturea Tab1e 6 lists generalized proprties and applicationstypical Of se1ected aluminum al10ys. More detai1ed informationOn propertiescan be found in the artic1es"PropertiesOf Pure A1uminumt" "Proprties Of Wrought A1uminum A1l0YS*" and "Properties Of Cast A1uminum Alloys'' in this Volume.

'

Manufactured Forms Aluminum and its alloys may be cast or formed by virtually all known processes. Manufactured forms of aluminum and aluminum alloys can be broken down into two groups. Standardized products include sheet, plate, foil, rod, bar, wire, tube, pipe, and structural forms. Engineered products are those designed for specific applications and include extruded shapes, forgings, impacts, castings, stampings, powder metallurgy (P/M) parts, machined parts, and metal-matrix composites

(MMCs). A percentage distribution of major aluminum products is presented below (Ref 1):

rolled in line to approximately 9.4 to 12 mm (0.375 to 0.50 in.) diameter.

produfl rarm

Engineered Products

DlsMbutim946

sheet,plate,andfoil

54.5

hot Exmsionsand hlbe

23.7 14.6 7.1

Other(a)

(a) Includesconductor(3.7%);rod,bm. a d wire (1.9%);foxings and impacts (0.9%);and powder(0.696)

Standardized Products Flat-rolled pro&& include plate (thickness equal to or greaterthan 6.25 mm, 0r0.25 in.), sheet (thickness 0.15 rnm through 6-25 a or 0.006 through 0.25 in.), and foil (thickness less than 0.15 mm, or 0.006 in.). These produrn are semifabricated to rectangular cross section by sequential reductions in the thickness of cast ingot by hot and cold rolling. Properties in workhardened tempers are controlled by degree of cold reduction, partial or full annealing, and the use of stabilizing treatments. plate, sheet, and foil p d u d in heat-treatable compositions may be solution heat treated, quenched, precipitation hardened, and themally or mechanically stress relieved. Sheet and foil may be rolled with textured surfaces. Sheet and plate rolled with specially prepared work rolls may be embossed to produce products such as tread plate. By roll forming, sheet in corrugated or other contoured configurationscan be produced for such applications as roofing, siding, ducts, and gutters. While the vast majority of flat-rolled prod~ c t sare produced by conventional rolling mills, continuous processes are now in use to convert molten alloy directly to reroll gages. Strip casters employ countemtating watercooled cylinders or rolls to solidify and partially work coilable gage reroll stock in line. Slab casters of either twin-belt or moving block design cast stock typically 19 mm (0.75 in.) in thickness which is reduced in thickness by in-line hot reduction mill(s) to produce coilable reroll. Future developments based on technologicaland operationaladvances in continuous processes may be expected to globally affect industry expansions in flat-rolled product manufacture. Wire, rod, and bar are produced h m cast stock by extrusion, rolling, or combinations of these p s s e s . Wm may be of any cross section in which distance between parallel faces or opposing surfaces is less than 9.4 mm (0.375 in.). Rod exceeds 9.4 mm (0.375 in.) in diameter and bar in square, rectangular, or regular hexagonal or octagonal cross section is greater than 9.4 mm (0.375 in.) between any p a d e l or opposing faces. An increasingly large proportion of rod and wire production is derived from continuous processes in which molten alloy is cast in water-cooled wheeUmold-beltunits to produce a continuous length of solidified bar which is

9

Aluminum alloy castings are routinely produced by pressure-die, permanent-mold, green- and dry-sand, investment, and plaster casting. Shipment statistics are provided in Table 7. Prmss variations include vacuum, low-pressure, centrifugal, and pattern-related processes such as lost foam. Castings are produced by filing molds with molten aluminum and are used for products with intricate contours and hollow or cored areas. The choice Of Castings over other product f o m is often based on net shape considerations. Reinforcing ribs, internal passageways, and complex design features, which would be costly to machine in a part made from a wrought product, Can often be cast by appropriate pattern and mold or die design. premium engineered castings display extreme hteglit)', close dimensional tolerances, and consistently controlled mechanical properties in the upper range of existing high-strength capabilities for selected alloys and tempers. Extrusions are produced by forcing solid metal through apedies. Designs that are symmetrical around one axis are especially adaptable to production in extruded fom. With current technology, it is also possible to extrude complex, mandrelcored, and asymmetrical configurations. Precision extrusions display exceptional dimensional control and surfax finish. Major dimensions usually q u i r e no machining; tolerance of the asextruded product often permits completion of part manufacture with simple cutoff, drilling, broaching, or other minor machining operations. Extruded and extrudeddrawn seamless tube competes with mechanically seamed and welded tube. Forgings are produced by inducing plastic flow through the application of kinetic, mechanical, or hydraulic forces in either closed or open dies. Hand fotghgs are simple geometric shapes, formable between flat or modestly contoured opendies suchas mtangles, cylinders(mu1tiface rounds), disks (biscuits), or limited variations of these shapes. These f-gs fill a frequent need in industry when only a limited number of pieces is required, or when prototype designs are to be proven. Most aluminum forgings are produced in closed dies to produce parts with good surface finish, dimensional control, and exceptional soundness and properties. Precision forgings emphasize near net shape objectives, which incorporate reduced draft and more precise dimensional accuracy. Forgings are also available as rolled or mandrel-forged rings. Impacts are formed in a confining die from a lubricated slug, usually cold, by a single-stroke application of force through a metal punch causing the metal to flow around the punch and/or through an opening in the punch or die. The process lends itself to high production rates with a precision part being produced to exacting quality and dimensional standards. Impacts are a

Table 6 Typical propertiesand applicationsof comnonly used wrought aluminum alloys

Alloy and

temper

11Oo-o 1100-HI4

ultilnate tendle strength MPa ksi 90 124

13 18

Yield strength MPa ksi

34

5

117

17

35 9

45 20

4 24 43 45

...

... ...

... ... ... ...

1350-0 135GH19 2011-T3 2011-T8

186

12 27

379 407

59

28 165 2% 310

2014-0 2OWT4. T451 2014-T6, T651 2017-T4, T45l

427 483 427

27 62 70 62

97 290 414 276

14 42

2024-0 2024-T3 2024T4, T351

186 4x3 469

27 70 68

76 345 324

I1 50

2024-0 2024-T3 2024-T4, T35 1

179 448 44 1

26 65

64

76 310 290

22 19-0 2219-T87 3003-0 3003-H 12 3003-H 14 3003-H 16

I72 416 1 IO 131 I52 I79

25 69 16 19 22 26

76 393 41 124 145 172

3004-0 3WH38

I79 2x3

26 41

248

Alclad:

83

186

55

69

EbngnthninSOmm(2in.), % 16mm(Y16in.) 13mm(lL?in) Stre5thick diameta General carrosim Cold specimen specimen camsim(a)cra&ig(b) vmk&Wy(c)

A A

A

A A

A

A A

A

Joiningcharxteristicstd) Glls Arc Spdand

w h i n -

nbiSty(c)

Brazing

welding

E D

A

A A

E

A

A

welding amw welding A A

A

A

B A

B

...

...

...

...

...

...

...

...

D D

D B

C D

A A

D D

D D

D D

D D

18 20 13 22

...

...

...

D B B B

D D D D

D D D D

D B B B

B B B B

22

...

...

...

47

20 18 20

C C

D B B

D D D

D C C

D B B

D B B

11 45 42

20 18 19

... ... ...

...

...

B

C C

A C C

D B B

B B B

D C C

D B B

D B B

II

18

...

...

...

... D A A B C

... B E E D D

D D A A A A

D A A A A A

A A A A A A

B A B A A A

A A

A C

D C

B B

A A

A A

B A

60 40

57 6 18

21

25

IO 36

... ... ...

15 12

... 19

D D D

D D

B

IO

...

30 IO 8 5

40 20 16 14

D A A A A

20

25 6

A A

5

C C C C C

B A A A A

C D C

'

Description and selected applicatiam Commercially pure aluminum highly resistantto chemical attack and weathering. Low cost, ductile for deep drawing, and easy to weld. Used for high-purity applicationssuchas chemicalpessingequipment. Also fornameplates, fan blades, flue lining, sheet metal work, spun holloware,and fin stock Electricalconductors Screw machine products. Appliance parts and trim, ordnance,automotive,electronic,fasteners,hardware, machine parts Truck frames,aircraftstrucms, automotive,cylinders and pistons, machineparts, s t r u c t d s Screw machine products, fittings, fasteners, machine parts for high-strength s t ~ c t applications. d Excellent machinabilityin the T-tempers.Fair workability and fair corrosionresistance.Alclad 2024 combines the high strengthof2024withthecorrosionresistanceof the commercially pure cladding. Used for mck wheels, many ~ t ~ c h u aircraft ;il applications,gears for machinery,screw machine products,automotive parts, cylindersand pistons, fasteners,machine parts, ordnance,recreation equipment, screws and rivets Structdusesathightemperature(to315"C,or 600°F).High-strengthweldments Most popular general-purposealloy. Strongerthan 1100 with same good formabilityand weldability. For generaluse including sheet metal work, stampings,fuel tanks, chemical equipment, containers,cabinets, freezer liners, cooking utensils, pressure vessels, builder's hardware, storagetanks, agricultural applications,appliance parts and trim, architectural applications,elecmnics, tin stock, fan equipment, name plates, recreationvehicles, trucks and Wilers. Used in drawing and spinning Sheet metal work, storagetanks, agricultd applications,buildingproducts, containers,electronics, furniture,kitchen equipment, recreation vehicles, trucks and trailers

(continued) (a) General corrosion rating: A, B, can be used in industrial and

developed.

ospheres without protection. C. D, E, generally should be protected, at least on faying surfaces. Note that these alphabetical listings are relative ratings in descending order: A = best re in service or in laboratory tests. B, no known instance of failure in service; limited failures in labmtoly tests of short transverse specimens.C, service failure with sustained tension imited failures in laboratory tests of long transverse specimens. D, limited service failures with sustained longitudinalor long transverse mas.(c) Cold workabilityand machinability ratings: is best rating, etc. (d) Brazeability and weldabilityratings: A, generally weldable by all commercial procedures and methods. B, weldable with special techniques or for specific applications re and weld performance. C, limited weldability because of crack sensitivity or loss in resistance to corrosion and mechanical properties. D, no commonly used welding methods have been

Table 6 (continued) ElongationinSOmm(Zin.), ?6 t6mm(1/16h) l 3 m (ID in.)

Alloyand temper

Ultimate tensilestrength MPa ksi

Yiild strength MPa ksi

3105-0 3105-H14 3 105-H18 3105-H25

117 172 2 14 179

17 25 31 26

55 152 193 159

8 22 28 23

24 5 3

...

5005-H34

159

23

138

20

8

5052-0 5052-H112 5052-H32 * 5052-H34

193

28

90

13

25

30

228 262

33 38

193 214

28 31

12 10

5056-0 5056-H18 5083-0 5083-H321

290 434 290 317

42 63 42 46

152 407 145 228

22 59 21 33

5086H32 5086-H34 5086-H112 5454-0 5454-H32 5454" 5454-H 1 12

290 324 269 248 276 303 248

42 47 39 36 40 44 36

207 255 131 117 207 241 124

30 37 19 17 30 35 18

...

...

...

...

strescormsion CoM cormsim(a)crackiig(b) workabirty(c)

Machinability(c)

Brazing

welding

welding

seamwelding

... ...

A A A A

A A A B

A B C

?

E D D A

A A A A

A A A A

A A A A

B A A A

...

A

A

B

D

B

A

A

A

18 14

A A A A

A A A A

A B A B

D D D D

C C B B

A A A A

A A A A

B A A A

... ... ...

35 10 22 16

A A A A

B C A A

A C B C

D C D D

D D D D

C C C C

A A A A

B A B A

12 IO 14 22 10 10 18

... ... ... ...

A A A A A A A

A B A A A A A

B B B A B B B

D C D D D C D

D D D D D D D

C

A A A A A A A

A A A B A A A

thick

diameter

specimen

specimen

...

...

... ...

...

...

... ...

General

Joidnpcharacteristks(d) Gm Arc Spatand

C C C C C C

Dexriptmnand sewedapplications Residential siding, mobile homes, rain-canying goods, sheet metal work, appliance parts and aim, automotive parts. buildingproducts,electronics,fin stock, furniture, hospital and medical equipment, kitchen equipment, recreation vehicles, tmcks and trailers Specified for applications requiring anodizing; anodized coating is cleaner and lighter in color than 3003. Uses include appliances, utensils, architectural, applications requiring good electrical conductivity, automotive parts, containers, general sheet metal, hardware, hospital and medical equipment, kitchen equipment, name plates, and marine applications Sbonger than 3003 yet readily formable in the intermediatetempers. Good weldability and resistance to corrosion. Uses include pressure vessels, fan blades, tanks, elecbonic panels, electronic chassis, mediumsmngth sheet metal parts, hydraulic tube, appliances, agricultural applications, architectural uses, automotive parts, buildingproducts, chemical equipment, containers, cooking utensils. fasteners, hardware, highway signs, hospital and medical equipment, kitchen equipment, marine applications, railroad cars, recreation vehicles, trucks and milers Cable sheathing, rivets formagnesium, screen wire, zippers, automotive applications, fence wire. fasteners Forall typesofwelded assemblies, marinecomponents, andtanks requiring high weldefficiency andmaximum joint strength. Usedinpressurevessels~pto65~C(l50 O F ) and in many cryogenic applications, bridges, freight cars,marinecomponents,TV towers,drillingrigs, mnsportation equipment, missile component?, and dump truck bodies. Goodcorrosion resistance Used in generally the same types of applications a?5083, particularly where resistance to either stress cornsion or atmospheric corrosion is important Forall typesofweldedassemblies, tanks,pressure vessels. ASME code approved to 205 "C (400 "0.Also used in trucking for hot asphalt road tankers and dump bodies; also, for hydrogen peroxide and chemical storage vessels

(continued) (a) General corrosion rating: A, B, can be used in industrial and seacoast atmospheres without protection. C, D, E, generally should be protected, at least on faying surfaces. Note that these alphabetical listings are relative ratings in descendingoder: A= best rating,etc.(b)Stress-cornsioncrackingrating: A,noknowninstanceoffailureinserviceorinlaboratory tests. B,noknowninstanceoffailure inservice; limited failures in laboratory testsofshorttransversespecimens.C, service failure with sustained tension stressactinginshorttmnsversedirectionrelativetograinstructure; limitedfailures inlaboratory testsoflongtransversespecimens.D, limitedservice failures with sustained longitudinal orlong transverse areas. (c)Cold workabilityandmdchinability ratings: alphabetical designations are relative ratings in descending order. Ais best rating, etc. (d) Blazeability and weldabilityratings: A, generally weldable by all commercial procedures and methods. B, weldable with special techniques or for specific applications that justify preliminary trials or testing to develop welding procedure and weld performance. C, limited weldability because of crack sensitivity or loss in resistance tocorrosion and mechanical properties. D, no commonly used welding methods have been developed.

Table 6 (continued)

temper

Ultimate tensile strength MPa b i

5456-H32Iand-H116

352

Allay and

51

Y ~ l strength d MPa b i

255

37

13x 55

20

145 276

35

552

thick

diameter

specimen

spfrimn

...

16

A A

A A

71

...

II

C

503

73

II

II

97 462

14 67

17

...

II

572

x3

22 I 524

32 76

7075-T6 and -T65 I Alclad: 7075-0 7075-T6 and -T65 I

C

... ...

490

7050-T765 I

27

B

12 12

X0

1x6 24 I

...

A

25 17

21 31

6063-T5 W3-T6

IX 35

General corrosion Cold corrosion(a) cradtmg(b) workpbihy(c)

B A B C

145 214

45

23

~

A A B A

21 40

159 I24 24 I 310

_

Strrsf

A B B B

12 25 22 12

6061-0 606 I -T4 606 I -T6 and -T65 I

5657-H25

Elongation ~ in 50 mm (2 in.), W _ 1.6mm(U16in.) I3 mm (10in)

-.~

X

30

Machinability@)

D

D D

Joiningcharacte+ies(d) Gm Arc Spatand Brazing welding welding seamwelding

D

C

A

A

C

B A A A

A A A A

A A A A

A B A A

C

B

C C

A A

A A

A A

A A

B

D

B

D

D

D

B

C

C

D

B

D

D

D

B

...

...

B

C

D B

D D

D D

C C

D

C

C

Description and selected applications

For all types of welded assemblies, storage tanks, pressure vessels, and marine components.Used where best weld efficiency and joint strength are required. Restricted to temperatures below 65 "C(150 O F ) For anodized auto and appliance trim and nameplates Good formability, weldability,c o m i o n resistance,and strength in the T - t e m p . Good genetal-purpose alloy used for a broad range of snuctural applications and welded assemblies including huckcomponents, railroadcars. pipelines.marine applications, furniture, agricultural applications aircraft, architectural applications, automotive parts, building products, chemical equipment, dump bodies, electrical and electronicapplications, fasteners, fence wire, fan blades, general sheet metal, highway signs, hospital and medical equipment, kitchen equipment, machine parts, ordnance, recreation equipment, recreation vehicles, and storage tanks , Used in pipe d i n g , furniture,architectural extrusions, appliance parts and trim, automotive parts, building products. electrical and electronicparts, highway signs, hospital and medical equipment, kitchen equipment, marine applications,machine parts, pipe, railroad cars, recreationequipment, recreationvehicles, trucks and

aailers

...

D

B

High-smngth alloy in aircraft and other S t ~ c t mAlso ~. used inordnance and recreationequipment ForaifiraftandotherapplicationsrequiMg highest strengths.Alclad 7075 combines the strength advantagesof 7075 with the corrosion-resisting properties of commercially pure aluminumclad surface. Also used in machine parts and ordnance

(a) General corrosion rating: A. B. can be used in industrial and seacoast atmospheres without protection.C. D. E. generally should be protected at least on faying surfaces.Note that these alphabetical listings are relative ratings in descending o d e r A = best rating. etc. (b)Stress-msion crackingrating:A. no known instance of failure in service or in laboratory tests. B, no known instance of failure in service: limited failuresin laboratory tests of short transverse specimens. C, service failure with sustained tension stress acting inshort transversedirectionrelativetograin smucture: limited failuresin laboratory tests of long transverse specimens. D, limitedservicefailureswithsustained longitudinal orlong transverse areas. (c) Cold workability andmachinabilityratings: alphabetical designations are relative ratings in descending order. A is best rating, etc. (d) Brazeability and weldability ratings: A. generally weldable by all commercial procedures and methods. B, weldable with special techniquesor for specific applications that justify preliminary trials or testing to develop welding procedure and weld performance. C . limited weldability because of crack sensitivity or loss in resistance to corrosion and mechanical properties. D, no commonly used welding methods have been developed.

General Introduction / 11 Table 7 U.S. casting shipments from 1980 through 1990 Permanentand stmipermnnent Sand c&ingS For sak O m us(a)

Year

%tal astlngs

1980 1981 1982 1983

1,689.8 1,819.8 1,605.3 1,898.1

200.0 207.3 159.0 156.3

1984 1985 1986 1987 1988 1989 1990

2,232.8 2,229.8 2,204.8 2.220.2 2,316.2 2,193.9 2,134.0

183.3 188.7 197.6 227.3 225.9 217.6 204.5

mddcMings

Die enstings F a spk O m us(a)

F a s.le

Own uMa)

33.1 30.8 19.2 10.2

217.2 209.2 161.9 211.8

105.9 82.3 77.2 90.5

633.8 704.1 624.2 812.9

429.2 452.7 434.0 493.3

133,4

12.6 15.3 25.8 24.0 28.3 29.4 24.5

388.7 390.7 390.7 385.2 474.8 452.3 459.7

(b) (b) (b) (b) (b) (b) (b)

932.9 923.5 886.3 892.5 919.7 890.3

583.0 596.8 601.9 614.8 587.8 546.2 519.8

132.3 114.8 102.5 76.4 79.7 58.1 77.1

Other

70.6 129.8 123.1

aluminum Mh4Cs are the most commonly produced metal-matrix material. The benefits of these aluminum MMCs are that they have increased stiffness, strength and wear resistance along with enhanced thermal conductivity and a lower coefficient of thermal expansion Over the unreinforced aluminum alloy from which they are produced. Information on processing and properties of these materials can be found in the article “Aluminum-Matrix Composites” in this Volume.

Fabrication Characteristics

This section will briefly review important considerations in the machining, forming, forging, and joining of aluminum alloys. AddiNote: Values are given in millions of pounds. (a) Own use shipments are for captive consumption in the producer’s end products. (b) Permanent mold shipments for sale and tional informationcan be found jn the articles ownuse were combined in 1984. Source:Ref 1 in this Volume that deal with specitic fabrication processes. Machinability of most aluminum alloys is combination of both cold extrusionand cold forgFor more demanding applications, such as excellent (see, for exmple, the machinability ing and, as such, combine advantages of each aerospace parts or components requiring enratings in Table 6). Among the various wrought hanced resistance to stresscornsion cracking, and cast aluminurndays and mong the tempers process. There are three basic types of impact form- rapidly solidified or mechanically attrited alu- in which they are produced,thmis considerable ing-reverse impacting, forward impacting minum powders are consolidated by more ad- Kariation in machining characteristics, which and a combination of the two, each of which vanced techniques that result in close to 100% may require specid toolins or techniques.Hardmay be used in aluminum fabrication. Reverse of theoretical density. These consolidation ness ,& yield smngths are variously used as impacting is used to make shells with a forged methods include hot isostatic pressing, rapid approximationsof machinabdity. seethe article base and extruded sidewalls.The slug is placed omnidirectional compaction, ultra-high strain u ~ ~ ~ in this M volume ~ ~for ,more detailed in a die cavity and struck by a punch, which rate (dynamic) compaction, and spray deposi- information. forces the metal to flow back (upward) around tion techniques. using advanced P/kf processChemical milling, the moval of metal by the punch, through the opening between the ing methods, alloys that cannot be produced che,.,,icalamck in an alkaline or =id solution,is punch and die, to form a simple shell. Forward through conventional ingot metallurgy meth- routine for specid&d reductions in thichess. impacting somewhat resembles conventional ods are routinely manufactured. For complex large surface areas in which uniform Powder metallurgy parts may be competi- metal removal is required, Chemical milling is extrusion. Metal is forced through an orifice in the die by the action of a punch, causing the tive with forgings, castings, stampings, ma- often the most econohcal method. me pmess metal to flow in the direction of pressure appli- chined components,and fabricated assemblies. is used extensivelyto etch preformd aerospace cation. hnch/die clearance limits flash forma- Certain metal products can be produced only parts to obtain dum strength-to-weightmtion. Forward impacting with a flat-face punch by powder metallurgy; among these are oxide- tios (See Table 5). I n t e r n y stiffened aluminum is used to form round, contoured, straight, and dispersioned strengthenedalloys and materials wing a d fuselage sections are chemically d e d ribbed rods. With a stoprace punch, thin- whose porosity (number distribution and size to p&uce an optimum cross section and miniwalled parallel or tapered sidewall tubes with of Pores) is Controlled (filter elements and self- mum skin thickness. Spars, stringers, floor one or both ends open may be formed. In the lubricating bearings). Informationon the Prop- beams, and frames are frequent applications as combination method, the punch is smaller than erties and processing of aluminum P N parts well. See the article ‘‘Machining” in this volume an oriiiced die resulting in both reverse and can be found in the articles “Powder Metal- formore information. lurgy Alloys” and “Powder Metallurgy ROCforward metal flow. Formability is among the more h p o m t Powder metallurgy (P/M) parts a r e essing” in this Volume. characteristics of aluminum and many of its alMetal-matrix composites (MMCs) basi- loys. Specific tensile and yield strengths, ductilformed by a variety of processes. For less demanding applications, metal powder is com- cally consist of a nonmetallic reinforcement in- ity, and respective rates of work ha