Heat Treater's Guide: Practices and Procedures for Nonferrous Alloys

657 Pages·1996·78.33 MB·English

by  Harry Chandler

Heat Treater's Guide
Practices and Procedures for Nonferrous Alloys
Harry Chandler, Editor
Veronica Flint, Managerof Book Acquisitions
Grace M. Davidson, Managerof Book Production
Randall L. Boring, Production Project Coordinator
Cheryl L. Powers, Production Project Coordinator
Alexandru Popaz Pauna, Production Project Coordinator
cAS:~z
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Table of Contents
Introduction. ........................ 1 1050 149
Inconel 625 88
DiffusionProcess. ................ 1 1060 150
Nimonic75 97
Annealing Cold-WorkedMetals ..... 1 1100 151
RA-333 97
HomogenizationofCastings. ....... 4 1145 153
NA-224 97
PrecipitationHardening 1199 153
Cobalt-BaseAlloys 98
Treatments ................... 5 1350 154
S-816 98
DevelopingTwo-PhaseStructures. ... 6 2011 155
Stellite6B 98
2014, Alclad2014 155
Superalloys ........................... 9 Haynes25;L-605 99
2017 159
HeatTreatingSuperalloys............. 11 Haynes 188....................102
2024, Alclad2024. .............. 159
Characteristics " 11 MP35N 105
2048 169
HeatTreatingPractice " 12 MP159 106
2124 171
Nickel-BaseAlloys " 17 Air-Resist213 106
2218 173
Astroloy....................... 17 Elgiloy. .......................106
2219,Alclad2219 174
D-979 '" 19 V-36 107
2319 178
IN100 19 UMCo-50 107
2618 179
IN102 25 Iron-BaseAlloys 108
3003,Alclad3003 180
Incoloy901 " 26 A-286.. '" 108
3004,Alclad3004 182
Inconel706 " 29 W-545 112
3105 184
InconelX750 ......... 30 V-57 112
4032 184
Incone1751 33 Incoloy 800 112
4043 '" 185
HastelloyB " 33 Incoloy 801 114
5005 185
HastelloyB-2 " 33 Incoloy 802 115
5050 186
HastelloyC " 35 Incoloy807 115
5052 187
HastelloyC-4................... 36 Incoloy 825 115
5056,Alclad5056 188
HastelloyC-276 " 37 Incoloy903 117
5083 189
Hastelloy N " 37 Incoloy907 117
5086,Alclad5086 191
HastelloyS '" 37 Incoloy909 117
5154 191
HastelloyW " 38 Incoloy925 118
5182 192
Hastelloy X .................... 38 16-25-6 118
5252 193
Haynes214 39 17-14CuMo 119
5254 193
Haynes230 " 40 19-9DL 119
5356 194
Nimonic 86 .............. 40 N-155 119
5454 194
CustomAge625PLUS " 40 RA-330 120
5456 195
Haynes242 " 40 Discaloy. ......................120
5457 197
Incone1702 " 41 Haynes 556 121
5652 198
Incone1718 " 41 PyrometCTX-l. 122
5657 198
Inconel721 59 PyrometCTX-3 122
6005 200
Inconel722 " 59 Nickel. 123
6009 200
C-263 59 HeatTreatingNickel ................125
6010 201
Pyromet31 " 59 Nickel200 126
6061,Alclad6061. .............. 201
Nimonic 80A................... 60 Nicke1201 126
6063 206
Nimonic90 " 62 Monel400 127
6066 208
Pyromet 860 " 62 MonelR-405 127
6070 208
Refractory26 " 63 MonelK-500 127 6101 209
Rene41 63 AluminumAlloys 129 6151 210
Rene95 68 HeatTreatingAluminumAlloys 131 6201 , 211
Rene 100 69 StrengtheningbyHeatTreatment 135 6205 211
Udimet 500 " 69 HardeningofCastAlloys .........140 6262 212
Udimet520 " 70 StressRelief 140 6351 213
Udimet700 " 70 EffectsofReheating ............. 140 6463 214
Udimet710 " 74 Annealing .....................141 7005 214
UnitempAF2-lDA 74 GrainGrowth 142 7039 215
Waspaloy " 76 DimensionalChanges during 7049 217
NimonicPE16 " 81 HeatTreatment. 142 7050 218
NimonicPK33 " 81 QualityAssurance 142 7072 221
Inconel 600 " 81 TemperDesignationsforHeat-Treatable 7075, A1clad7075 221
Inconel 601 " 88 AluminumAlloys 144 7175 238
Inconel604 .................... 88 PropertiesofWroughtAluminum 7178, Alclad7178 239
Incone1617 " 88 andWroughtAluminumAlloys. .... 146 7475 241
V
AluminumCastingAlloys. ........... 244 C1l300,C1l400,C1l500,C1l600 C42500 (88.5Cu-9.5Zn-2Sn) 353
201.0 244 (99.96Cu+Ag- 0040) , 306 C43000 (87Cu-IO.8Zn-2.2Sn) 354 .
204.0 245 C12500,CI2700,C12800,CI2900, C43400 (85Cu-14.3Zn-0.7Sn) 354
206.0,A206.0 246 C13000 308 C44300,C44400,C44500
208.0 248 C14300,C14310 (99.90Cu-O.lCd; (71Cu-28Zn-lSn) 354
238.0 248 99.8Cu-0.2Cd) , 309 C46400,C46500,C46600,C46700
242.0 249 Cl4500(99.5Cu-0.Te) , 309 (60Cu-39.2Zn-0.8Sn) 356
295.0 250 Cl4700(99.6Cu-OA5) , 309 C48200 (60.5Cu-38Zn-0.8Sn-
296.0 251 Cl5000(99.85Cu-0.15Zr) 310 0.7Pb) 358
308.0 251 C15100 (99.9Cu-0.1Zr) , 312 C48500 (60Cu-37.5Zn-1.8Pb-
319.0 252 C15500 (99.75Cu-0.llMg- 0.7Sn) 359
332.0 252 0.06P) 312 C50500 (98.7Cu-1.3Sn) 359
336.0 252 Cl5710(99.8Cu-0.2Ah03) , 313 C51000 (94.8Cu-5Sn-0.2P) 360
339.0 253 C15720 (99.6Cu-0.4Ah03) , 313 C51100 (95.6Cu-4.2Sn-0.2P) 361
354.0 253 C15735 (99.3Cu-0.7Ah03) 314 C52100 (92Cu-8Sn) 361
355.0,C355.0 255 Cl6200(99Cu-1Cd) 314 C52400 (90Cu-IOSn) 362
356.0,A356.0 257 C17000 (98Cu-1.7Be-0.3Co) , 314 C54400 (88Cu-4Pb-4Sn-4Zn) 363
357.0,A357.0 259 Cl7200,C17300 , 316 C60600 (95Cu-5Al) 363
359.0 259 C17410 (99.2Cu-0.3Be-0.5Co) , 320 C60800 (95Cu-5Al) 363
360.0,A360.0.................. 260 C17500 (97Cu-0.50Be-2.5Co) , 321 C61000 (92Cu-8Al) 364
380.0,A380.0 261 C17600 , 323 C61300 (90Cu-7AI-0.3Sn) 364
383.0 261 Cl8100(99Cu-0.8Cr-0.16Zr- C61400 (91Cu-7AI-2Fe) 365
384.0,A384.0 262 0.04Mg) , 323
C61500 (90Cu-8AI-2Ni) '366
390.0,A390.0.................. 262 C18200, C18400,C18500
C62300 (87Cu-IOAI-3Fe) 367
413.0,M13.0 263 (99Cu-1Cr) 324
C62400 (86Cu-llAI-3Fe) 368
443.0,A443.0,B443.0,C443.0 264 C18700 (99Cu-1Pb) , 325
C62500 (82.7Cu-4.3Fe-13Al) 368
514.0 264 Cl9200(98.97Cu-1.0Fe-0.03P) .., 325
C63800 (95Cu-2.8AI-1.8Si-
518.0 265 Cl9210(99.87Cu-0.lFe-0.03P) .. , 326
OAOCo) 369
520.0 265 C19400 (Cu-2.35Fe-0.03P-
C65100 (98.5Cu-1.5Si) 370
535.0,A535.0,B535.0 266 0.12Zn) , 326
C65400 (95ACu-3.0Si-1.5Sn-
712.0 266 Cl9500(97Cu-1.5Fe-0.1P-
O.lCr) 370
713.0 267 0.8Co-0.6Sn) , 328
C65500 (97Cu-3Si) 370
771.0 267 C19700 (99.15Cu-0.6Fe-0.2P-
C68800 (73.5Cu-22.7Zn-3AAl-
850.0 268 0.05Mg) , 328
OACo) , 371
HeatTreatingAluminum-Lithium C21000 (95Cu-5Zn) , 328
C69000 (73.3Cu-22.7Zn-3AAl-
Alloys 269 C22000 (90Cu-IOZn) , 330
0.6Ni) , 372
Weldalite049 .................. 269 C22600 (87.5Cu-12.5Zn) , 331
C69400 (81.5Cu-14.5Zn-4Si) 372
2090 271 C23000 (85Cu-15Zn) , 332
C70400 (92ACu-5.5Ni-1.5Fe-
2091 274 C24000 (80Cu-20Zn) , 334
0.6Mn) 373
8090 276 C26000(70Cu-30Zn) 334
C70600 (90Cu-IONi) 373
CP276 279 C26800,C27000 (65Cu-35Zn) , 339
HeatTreatingAluminum PIMParts .... 280 C28000 (60Cu-40Zn) 341 C71000 (80Cu-20Ni) 375
HeatTreatableGrades ........... 280 C31400 (89Cu-9.lZn-1.9Pb) , 343 C71500 (70Cu-30Ni) 376
Applications ................... 280 C31600 (89Cu-8.1Zn-1.9Pb- C71900 (67.2Cu-30Ni-2.8Cr) 377
HeatTreatingTechnology 280 1Ni) , 343 C72200 (83Cu-16.5Ni-0.5Cr) 378
C72500 (88.2Cu-9.5Ni-2.3Sn) 378
CopperAlloys ....................... 283 C33000 (66Cu-33.5Zn-0.5Pb) , 343
C74500 (65Cu-25Zn-IONi) 378
HeatTreatingCopperAlloys. ......... 285 C33200 (66Cu-32AZn-1.6Pb) , 344
C75200 (65Cu-18Ni-17Zn) 379
Homogenizing ................. 285 C33500 (65Cu-34.5Zn-0.5Pb) , 344
C75400 (65Cu-20Zn-15Ni) 380
Annealing. .................... 285 C34000 (65Cu-34Zn-1Pb) 345
C75700 (65Cu-23Zn-12Ni) 381
StressRelieving ................ 286 C342PO(62Cu-36.2Zn-2Pb) , 345
Hardening. .................... 287 C35300 (62Cu-36.2Zn-1.8Pb) 345 C77000 (55Cu-27Zn-18Ni) 381
Copper-BerylliumAlloys 288 C34900 (62Cu-37.5Zn-0.3Pb) , 346 C78200 (65Cu-25Zn-8Ni-2Pb) 382
Copper-ChromiumAlloys 290 C35000 (65.5Cu-36AZn-l.lPb) 347 CopperCastingAlloys 393
Copper-ZirconiumAlloys......... 290 C35600 (62Cu-35.5Zn-2.5Pb) , 347 C81300 383
Miscellaneous Precipitation- C36000 (61.5Cu-35.5Zn-3Pb) , 347 C81400 , 383
HardeningAlloys ... ......... 291 C36500,C36600,C36700,C36800 C81500 , 383
Spinodal-HardeningAlloys 291 (60Cu-39AZn-0.6Pb) , 349 C81800 (97Cu-1.5Co-IAg-
Copper-Aluminum(Aluminum C37000 (60Cu-39Zn-lPb) , 349 OABe) 384
Bronze)Alloys 291 C37700 (60Cu-38Zn-2Pb) 349 C82000 (97Cu-2.5Co-0.5Be) 384
CopperCastingAlloys 292 C38500 (57Cu-40Zn-3Pb) 350 C82200 (98Cu-1.5Ni-0.5Be) 385
WroughtCoppersandCopperAlloys ... 295 C40500 (95Cu-4Zn-1Sn) , 351 C82400 (98Cu-1.7Be-0.3Co) 386
CIOIOOandC10200 295 C40800 (95Cu-2Sn-3Zn) 351 C82500 (97.2Cu-2Be-0.5Co-
CI0300 298 C41100(91Cu-8.5Zn-0.5Sn) 351 0.25Si) 386
CI0400,C10500, ClO700 298 C41500 (91Cu-7.2Zn-1.8Sn) , 352 C82600 (97Cu-2ABe-0.5Co) 387
CI0800 300 C41900 (90.5Cu-4.35Zn- C82800 (96.6Cu-2.6Be-0.5Co-
CllOOO(99.95Cu-0.040) 300 5.l5Sn) , 353 0.3Si) 388
C11l00(99.95Cu-0.040-0.01Cd) 306 C42200 (87.5Cu-ll.4Zn-l.lSn) 353 C83300 389
vi
C86100,C86200 (64Cu-24Zn EffectsofMajorVariables 420 Alpha-BetaAlloys 514
3Fe-5Al~~n) .. ............ 389 WroughtMagnesiumAlloys 423 Ti-5AI-2Sn-2Zr-4~o-4Cr 514
C86300 (64Cu-26Zn-3Fe- AZ3IB,AZ31C 423 Ti-6AI-2Sn-4Zr-6~o 517
3AI-4~n) .................. 390 AZ61A 424 Ti-6A1-4V 522
C86400 (59Cu-0.75Sn-0.75Pb-37Zn- AZ80A 425 Ti-6A1-6V-2Sn 536
1.25Fe-0.75AI-0.5~n) 390 HK31A 427 Ti-7AI-4~o 541
C86500 (58Cu-39Zn-1.3Fe-lAl- ~21A 429 T~TAL®62S 543
O.5~n) 390 ~31A 430 Ti-4.5AI-3V-2~o-2Fe 544
C86700 391 ZC71 431 IMI367 549
C86800 391 ZK60A 431 IMI550 549
C87300 (formerlyC87200). ...... 392 CastMagnesiumAlloys 432 IMI55l. 550
C87600 392 A~100A 432 Ti-6-22-22S 551
C8761O 392 AZ63A. 433 Ti-5AI-2.5Fe 556
C87500, C87800 (82Cu~Si- AZ81A 435 Ti-5AI-5Sn-2Zr-2~o-0.25Si 557
14Zn) 393 AZ91A,AZ91B,AZ91C, BetaandNear-BetaAlloys 559
C87900 393 AZ9ID,AZ91E 436 Ti-ll.5~o-6Zr-4.5Sn............ 559
C92200 (88Cu-6Sn-l.SPb- AZ92A. 438 Ti-3AI-8V-6Cr-4~o-4Zr
4.5Zn) 393 EQ21 ; 439 (BetaC).................... 563
C92300 (87Cu-8Sn-1Pb-4Zn) ..... 394 EZ33A 440 Ti-lOV-2Fe-3Al 566
C92500 (87Cu-llSn-1Pb-1Ni) .... 394 HK31A 441 Ti-13V-llCr-3Al 572
C92600 (87Cu-lOSn-1Pb-2Zn). ... 395 HZ32A 443 Ti-15V-3Cr-3AI-3Sn 577
C92700 (88Cu-lOSn-2Pb) 395 QE22A. 444 T~TAL®21S 582
C92900 (84Cu-lOSn-2.5Pb- QH21A 446 Ti-5AI-2Sn-4Zr-4~o-2Cr-IFe 584
3.5Ni) 395 WE43 447 Ti-8~o-8V-2Fe-3Al 586
C93200 (83Cu-7Sn-7Pb-3Zn) 395 WE54 448 Ti-15~o-5Zr. 589
C93400 396 ZC63 450 Ti-15~o-5Zr-3Al. 591
C93500 (85Cu-5Sn-9Pb-1Zn). .... 396 ZE41A 450 Ti-ll.5V-2AI-2Sn-llZr 594
C93700 (80Cu-lOSn-lOPb) 396 ZE63A 452 Ti-12V-2.5AI-2Sn-6Zr 595
C93800 (78Cu-7Sn-15Pb) 397 ZH62A. 453 Ti-13V-2.7AI-7Sn-2Zr 597
C95200 (88Cu-3Fe-9Al) ......... 398 ZK51A. 454 Ti-8V-5Fe-IAI 599
<::95300(89Cu-1Fe-lOA1) 398 ZK61A. 456 Ti-16V-2.5Al................... 601
C95400 (85Cu-4Fe-llAl)and TitaniumAlloys 457 HeatTreatingCastandPIMTitanium. .. 602
C95410 399 HeatTreatingTitamiunAlloys 459 ModifyingMicrostructure ........ 602
C95500 (81Cu~Fe-4Ni-llAl) 399 AlloyTypesandResponse to HotIsostaticPressing 602
C95600 (91Cu-2Si-7Al) 399 HeatTreatment. 459 WeldRepair ................... 602
C95700 (75Cu-3Fe-8AI-2Ni-
StressRelieving 460 ZincAlloys ......................... 607
12~n) 400 Annealing 460 HeatTreatingZincAlloys ............ 609
C95800 (82Cu-4Fe-9AI-4Ni-
SolutionTreatingandAging 461 HeatTreatmentofZamakand
l~n) 400 HighPurityTitanium 463 ZAAlloys .................. 609
C96600 (69.5Cu-30Ni-0.5Be). .... 400
CommerciallyPureandModified ReasonsforHeatTreating ........ 609
C97300 (56Cu-2Sn-lOPb-
Titanium ....................... 467 SupportingDocumentation ....... 609
20Zn-12Nij 401
UnalloyedTitanium, ASNGrade 1, Conventional ZincDie
C97600 (64Cu-4Sn-4Pb-8Zn-
UNSR50250 467 CastingAlloys 615
20Ni) 401
UnalloyedTitanium,AST~Grade2, AC43A 615
C97800 (66.5Cu-5Sn-l.5Pb-2Zn-
UNS R50400 469 AG40A 615
25Ni) 401
UnalloyedTitanium,AST~Grade3, AC41A 616
C99400 (90ACu-2.2Ni-2.0Fe-
UNSR50550 471 AG40B 616
1.2Al-1.2Si-3.0Zn)........... 401
UnalloyedTitanium,Grade4,UNS Zinc-AluminumCastingAlloys 617
C99500 402
R50700 472 ZA-8 617
C99750.. '" '" 402 ModifiedTi(Ti-0.2Pd),Grade7, ZA-12 617
Berylliumcopper21C(97Cu-
UNSR52400;Grade 11,
ZA-27 618
2Be-1Co) 402
UNSR52250 474
Berylliumcoppernickel72C LeadAlloys 619
Ti-0.3~o-0.8Ni,AST~Grade 12,
(68.8Cu-30Ni-1.2Be) 403 HeatTreatingLeadandLead
R53400 476
HeatTreatingBeryllium Alloys 621
AlphaandNear-AlphaAlloys 478
CopperAlloys ................... 404 Solid-SolutionHardening 621
Ti-3AI-2.5V 478
SolutionAnnealing ............. 404 SolutionTreatingandAging ...... 621
Ti-5AI-2.5Sn 483
AgeHardening. ................ 404 DispersionHardening 621
Ti-6AI-2Nb-ITa-0.8~o 488
Underaging, PeakAging,and Fabrication .................... 622
Ti-6AI-2Sn-4Zr-2~o-0.08Si. 492
OveragingTreatments ........ 404 ColdStorage. .................. 622
Ti-8Al-l~~-1V 498
SinteringCopper-BasedMaterials 412 ServiceTemperatures............ 622
TillETAL 1100 502
Production SinteringofBronze 412 IMI230 504 RefractoryMetalsandAlloys ........... 625
ProductionSintering ofBrass IMI417 505 HeatTreatingRefractory
andNickelSilvers ........... 412 IMI679 506 Metals andAlloys 627
MagnesiumAlloys 415 IMI685 509 GeneralAnnealingTreatments. .... 627
HeatTreatingMagnesiumAlloys. ..... 417 IMI829 510 MolybdenumandTungsten
TypesofHeatTreatment. ........ 417 IMI834 511 Annealing Practice 627
vii
Tantalum andNiobiumAnnealing HeatTreatingTin-RichAlloys , 633 Glossary 635
Practice .................... 628 BinaryAlloys. ................. 633
ConversionTables 647
TernaryAlloys , 633
Tin-RichAlloys. ..................... 631 Pewter 633 Cross Reference 651
viii
PREFACE
Heat Treater's Guide, Practices and Procedures for Nonferrous Metals/Alloys, features quick
accesstosome450 ormoreauthoritativedatasheetsonthesubject,namely:
• Superalloys
• Nickels
• Aluminum
• Copper
• Magnesium
• Titanium
• Zinc
Inaddition,briefoverview articlesprovideinformation ontheheattreatmentof:
• AluminumPIMalloys
• Beryllium-copperalloys
• Leadandleadalloys
• Refractorymetalsandalloys
• Tin-rich alloys
• andSinteringofcopper-basematerials
Information is organized by material group, and is provided on an alloy-by-alloy basis. Each
datasheet includes information such as:composition, trade names and common names, specifica
tions(bothU.S.andforeign),typicalapplications, mechanical andchemical properties,fabrication
characteristics, and, of course, the reconunended heat treating practice. These datasheets are de
s
signedtofollowasimilarformattothatestablishedinthepopularHeatTreater Guide, Procedures
andPracticesforIronsandSteels.
Accesstothisdataisfacilitatedbythecrossreferenceprovidedattheendofthebook.
For further convenience tothereader, we have included aGlossry of termsrelated tothe heat
treatingofnonferrous materials.
Weareinterested inreceiving datasheet contributions youmight have thatcouldbe included in
thisbook, aswellasyourconunents orsuggestions.
MaterialsPark, OH
September1996
iii
Introduction
The principles which govern heat treatment ofmetals and alloys are The diffusion process is involved in nearly all heat treatments for
applicabletobothferrousandnonferrous alloys.However,inpracticethere nonferrous alloys.
are sufficientdifferences to makeit convenientto emphasize asseparate Commontreatments include:
topics thepeculiaritiesofthealloysofeach classin theirresponse toheat
treatment. For example, in nonferrous alloys, eutectoid transformations, • Annealing aftercold working
which play such a prominentrole in steels, are seldom encountered, so • Homogenizationofcastings
there is less concern with principles associated with time-temperature • Precipitationhardeningtreatments
transformationdiagrams andwithmartensiteformation. Ontheotherhand, • Developmentoftwo-phase structures
theprinciples associated withchemical homogenizationofcaststructures
areapplicable tomanyalloysinbothclasses.
Diffusion Process
Intheheattreatmentofmetalsandalloys,therateofstructuralchange Fig. 1 Schematic representation of two possible diffusion
usually is controlled by the rate at which atoms in the lattice change mechanisms. (a)Twoatomsmovesimultaneouslytoexchange
positions. Forexample,whencold-workedcopperisannealedandsoftens, positions.(b)Fouratoms movecooperativelytorotatesimultane
oranaluminum-basealloy isaged,itisimportanttoknow howtheatoms ouslytom.ov.et.on.ewpo.sit.ions
. .. .
move relative to each othersoas tobring about theobserved changes in ••.•.•.••• ••..•.•.•.•..•
properties. This movement of atoms is called diffusion. Two different ••••"••• •••••••
diffusionmechanisms areshown inFig. 1.
~ • •• W ••
••••••• •••••••
••••••• •••••••
••••••• •••••••
(a) (b)
Annealing Cold-Worked Metals
Cold working increaseshardness, yieldstrength, andtensilestrength, termrecovery.Electricalconductivityisoneofthepropertiesinvolved(see.
and lowers ductility. Also, electrical resistivity is improved because in Fig.4).
creasing density ofdislocationsscatters theelectrons. The effects ofcold Recrystallization. With longer times or at higher temperatures, the
working onseveralpropertiesareshowninFig.2. structure undergoes a more radical change. Small crystals appear which
RoleofAnnealing. Inshapingmetalsbycoldworking,thereisalimit contain alow dislocation density (of amagnitudesimilar to thatprior to
totheamountofplastic deformationpossiblewithoutfracture. Annealing cold working) and arerelatively soft.Crystals nucleate inregions ofhigh
restores themetaltoastructural condition similartothatpriortodeforma dislocationdensity,andinthemicrostructureappearatorneardeformation
tion,making furthercold workingpossible. bands. Withtime,thenucleigrow,andmorenuclei formintheremaining
Changes instrength thattakeplaceduring annealing areindicated by cold-workedmatrix.Eventually, grainscontacteachother(atthattimethe
thehardnessdatainFig.3(a).Inthisinstance,dataareforafixedtempera originalcold-workedmaterialhasdisappeared).Theformationofgrainsis
ture.Asimilarresultisobtained byannealingforafixedtimeatincreasing referredtoasrecrystallization. Atthistime,strengthdropsdrastically (see
temperatures (Fig.3b). Fig.3and4).
Recovery, recrystallization, and grain growth are stages in Growthingrainsize.Microstructuralchanges thatoccur during an
annealing. The stage forshorttimesatlow temperatures inwhichhard nealing areillustratedinFig.5.During recovery, thedensityofdeforma
ness remains constant, orincreases slightly, iscalled therecovery region. tion bands drops, but the change is not marked. When crystallization
Dislocations undergo movementby thermal activation, being rearranged commences, small, equiaxed grains begin toappear (seemicrograph2in
into arrays somewhatmore stable andmore difficult tomove thanin the Fig. 5, and a recrystallized nucleus shown inFig. 6). Grains continue to
coldworked, unannealedcondition. Aslight increase inhardness results. form andtogrow untilthecold-workedmatrixisconsumed,whichmarks
Some propertiesregain values theyhad priortocold working. Hence the theend of therecrystallization period and thebeginningofgrain growth.
2/HeatTreater's Guide: NonferrousAlloys
120.-------.------,---.--------, Fig.2 Effectofcoldworking(byrollingat25°C,or77°F)onthe
tensile mechanical properties and hardness of oxygen-free,
high-conductivity(OFHC)copper
.~
§ 100\----+-------11----+-------1
LIVE GRAPH
"!0 Click here to view
'o"
'0
.s 80f----/--+-----I----+-------I
.s
-S
cO:l
~
t> 60If----+-yieldstrength,ksi--+:=~---1
"c0:
'"
c:
o Hardness,HB
.~
g> 40\-----,,,L-----Y'--------I----+-------I
o
Qi
~
c:
"E
'"
J:
o
L..-__-'--__-'-__---J'--_----'
o 20 40 60 80
Reductioninarea,%
Fig.3 (a)Effectofannealingtimeatfixed
temperature(400°C, or750 OF)on hard
140 ness ofaCu-5Zn solid-solutionalloycold
worked 60%. (b)Effectofannealingtem
<, perature at fixed time (15 min) on hard
1201--\--+--+--+---1 120 \ nessofaCu-5Zn solid-solutionalloycold
worked 60%
a:l J:
~ 1001------'1f-+---f---+--+--+---1 Ca,l100
~ Vi LIVE GRAPH
lI)
c: cQ): Click here to view
~ 80f-----\t------.f-=+_---+---+--+--I ~ 80
J: J:
\ Cu-5Zn
60 -, LIVE GRAPH
Click here to view
See Fig14for microstructures
r--
at numberedregions
40L..-_-'-__..L-_---L__--'-_----' 40
o 20 40 60 80 100 o 200 400 600 800 1000
lime,h lime,h
la) lb)
Annealingtemperature,of Fig.4 Effectofannealingtemperatureonhardnessandelectri-
390 750 1110 1470 calresistivityofnickel.The metal hasbeen cold worked at25°C
120 60 (77OF)almosttofracture. Annealingtime,1h
'#.
100~\ '>0H..a..rId>.n..e~s~ 50 'is LIVE GRAPH
't; Click here to view
aa::l '0~;
J: 80 40
lVI)i 1\ «.~i
cQ): t
"J'E": 60 \ 30 .QQsi)
<, Q)
40 20 'cO":l
.c
Resistivit;-1'0-... u
I
20 10
0 200 400 600 800
Annealingtemperature,°C
Introduction/3
Withfurtherannealing,grainsizecontinuestogrow(seemicrographs3,4, Asaruleofthumb,therecrystallizationtemperatureisapproximately
and5inFig.5). 0.3to0.6oftheabsolutemeltingpoint.InthecaseofCu-Znsolidsolution
Because annealing of cold-worked metals usually is carried out to alloys, the addition of zinc to copper lowers the melting point, and the
softenthematerial,thetemperatureandtimeneededtocompleterecrystal recrystallization temperature will decrease for high zinc contents (20 to
lizationmustbeknowntodeterminetheproperheattreatment.Therecrys 30%,forexample),seeFig.7.
tallization temperature is commonly referred to as an indicator of the
temperature atwhichmetalmustbeannealed forsoftening.
Fig. 5 Microstructure of a CU-5Zn alloy,
127 Rockwell B
cold rolledto60%,then annealedfordiffer
128 Rockwell B Recrystallizationjust beginning
enttimesat400°C(750OF).Thenumbersre
No recrystallization yet;still in recovery fer to the differentannealingtimes shown in
Fig.3(a)
OM
100urn
63RockwellB
Recrystallizationessentiallycomplete;
graingrowth beginning 60 Rockwell B
OM OM
I I I I
100urn 200llm
58 Rockwell B
OM
I I
200 IJ.m