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26 42005 8 TRANSACTIONSOFMATERIALSANDHEATTREATMENTVol.26 No.4August2005田 鹏1,2, 惠卫军2,3, 刘荣佩1, 张步海3, 于同仁3, 苏世怀3(1.,650093;2.,100081;3.,243000) :700℃35K。,(DIF);,,DIF“S”,,,DIF,。700℃,DIF“S”,0.7。,、、,。,、。:; ; ; :TG142 :A :1009-6264(2005)04-0069-05: 2004-10-12; : 2004-12-12: (2003AA331030): (1976—),,,,,5,:(010)62182791,E-Mail:tianpeng1976@sina.com。 [1～3],,,,“”,。,,(DIFT),(TMCP),。700℃。1 实验用料及方法35K,10mm,(,%):C0.36,Si0.14,Mn0.62,P0.02,S0.005。Thermo-CalcA1719℃,A3786℃。Formaster5℃sAr3645℃。GLEEBLE-20001,8mm×15mm。,、3%,S-4300(SEM),SISCIASV8.0。1 Fig.1 Schematicdiagramofthethermomechanicalprocess(W.Q-waterquenching,C.C-controlledcooling,A.C-aircooling)2 实验结果与分析2.1 21。3。,950℃780℃,;950℃(DOI:10.13289/j.issn.1009-6264.2005.04.0172 (﹒ε=20s)Fig.2 Microstructureevolutionofthesteeldeformedatdifferenttemperatures(﹒ε=20s)(a)950℃,ε=0,W.Q;(b)780℃,ε=0,W.Q;(c)950℃,ε=0.7,W.Q;(d)950℃,ε=0.7,C.C;(e)800℃,ε=0.7,W.Q;(f)800℃,ε=0.7,C.C;(g)700℃,ε=0.7,W.Q;(h)700℃,ε=0.7,C.Cγ),+,,,、,。800℃(DIF),15%,,,θ,。700℃,,65%,54%11%;(),,,。(700℃),。3S,,800℃(A3),γ※α;800～750℃(A3),;750℃,γ※α,(),。3 (VF)(TD)(ε=0.70,﹒ε=20s)Fig.3 VolumefractionofDIF(VF)asafunctionofdeformationtemperatures(TD)(ε=0.70,﹒ε=20s)70 262.2 1700℃42(g)、(h)。5。,(ε=0),700℃645℃,,,,,A1,;0.15,,,,;。,,,,(),,,,,。0.500.70,。4 700℃(﹒ε=20s)Fig.4 Microstructureevolutionofthesteeldeformedat700℃fordifferentdeformationstrains(﹒ε=20s)(a)ε=0.15,W.Q;(b)ε=0.15,C.C;(c)ε=0.30,W.Q;(d)ε=0.30,C.C;(e)ε=0.50,W.Q;(f)ε=0.50,C.C;(g)ε=0,W.Q;(h)ε=1.20,W.Q 5S,,γ※α;,;(),,。,,,。2.3 —700℃—6。,,,;,;714 :5 (VF)(ε)(TD=700℃,﹒ε=20s)Fig.5 VolumefractionofDIF(VF)asafunctionofamountofdeformation(ε)(TD=700℃,﹒ε=20s)6 700℃—Fig.6 Truestress-truestraincurvesofthesteeldeformedat700℃fordifferentamountofdeformation,,,ε=0.4,;,、。,,、。3 讨论,。695kJ/mol(166/)[4],7 (a)DIF(b)Fig.7 Schematicillustrationofthemicrostructuralevolutionformediumcarbonsteel(a)AusteniteadjacenttoDIFgrainboundariestransformsintosphericalorrod-likecementite;(b)Deformedaustenitetransformsintodegeneratedpearlite408kJ/mol,。,,(),,,,。,,35K,54:46,65%,0.998%,0.77%,、,。,,;6.69%,,(DIC)[5];。,、、,[6],:a),,;b),,;7。72 264 结论(1),。,“S”,800℃,;800～750℃,;750℃,,;(2)700℃,,“S”,,;,;,。0.7;(3),、、,,:a),;b),。1 ,,.[A].[C].,2001:311～314.LiWJ,WangGD,LiuXH.Grainrefinementandcarbideprecipitationforlowcarbonsteel[A].NewGenerationSteels'2001[C].Beijing,2001:311～314.2 SunZQ,YangWY,YangP,etal.Microstructureevolutionduringdeformationofundercooledausteniteinlowcarbonsteel[A].NewGenerationSteels'2001[C].Beijing,2001,35～40.3 ,,.[J].,2002,24(5):519～524.YangP,HaoGR,SunZQ.Coarseningtendencyofultra-fineferriteinlowcarbonsteels[J].JournalofUniversityofScienceandTechnologyBeijing,2002,24(5):519～524.4 ,, ,.[J].,1991,13(3):117～121.WuF,ZengXY,BianB,etal.Deformationinducedcarbiderapidspheroidizationformediumcarbonsteel[J].JournalofNationalUniversityofDefenseTechnology,1991,13(3):117～121.5 HuiWJ,DongH,WengYQ,etal.Effectofcontrolledrollingandcoolingonspheroidizationofcarbidesinmediumcarbonsteel[A].SecondInternationConferenceonAdvancedStructuralSteels[C],Shanghai,2004,689～694.6 ,.[J].,1999(2):21～25.WeiCH,WangXQ.Unusualdecompositionofundercoolingausteniteandcarbidegranulation[J].HotWorkingTechnology,1999(2):21～25.734 :studied.Theultimatetensilestrengthandhardenssofthesteelreachtothemaximumvaluesafteragingat535℃duetotheprecipitationofcoherentphase.Thestrengthandhardnessofthesteelagedattemperaturehigherthan535℃decreaseduetothecoarseningoftheprecipitatesandthedestructionofitscoherentrelationshipwithmatrix.Keywords:aging;martensiticlath;precipitationphase;mechanicalpropertiesBehaviorofHotDeformationanditsEffectFactorsforTC4TitaniumAlloyWANGQing,LIZhong-hua,SUNDong-li,WUGao-hui(SchoolofMaterialsScienceandEngineering,HarbinInstituteofTechnology,Harbin150001,China)TransMaterHeatTreat,2005,26(4):56～59,figs5,tabs1,refs14.Abstract:Truestress-truestraincurvesofTi-6Al-4VtitaniumalloyweremeasuredbyGleeble-1500FormasterPressSimulatoratdifferenttemperaturesanddifferentstrainrates.Themicrostructuresofthealloybeforeandafterdeformationwereobservedusingopticalmicroscope.Theeffectofdeformationtemperature,strainrate,originalmicrostructureandheattreatmentprocessingonhotdeformationbehaviorofTi-6Al-4Valloywereanalyzed.Theresultsshowthatat8.3×10-3sstrainrate,thedynamicrecoveryisthemainsofteningmechanisminthealloydeformedat600℃,andthedynamicrecrystallizationisthemainsofteningmechanisminthealloydeformedat800℃～900℃.However,thedynamicrecoveryandthedynamicrecrystalizationmayoccursimultaneously.Thehotdeformationresistanceofthealloyisimprovedbyquenchingoraging,andlesssensitivetothestrainrateintherangeof8.3×10-2s～8.3×100s,butthehotdeformationresistancedecreasesgreatlyat8.3×10-3sstrainratewhenthealloyisdeformedat600℃.Theflowstressofwidmanstättenstructureisgenerallyhigherthanthatofequiaxedgrainstructure.Keywords:Ti-6Al-4Vtitaniumalloy;hotcompressdeformation;microstructureStudyonMicrostructureandCompressiveMechanicalPropertiesofAluminumAlloyFoamsCHENGHe-fa1,HUKong-gang1,XUEGuo-xian,TIANJie2,ZHANGZhang1,DAIGuang-xing1(1.SchoolofMaterialScienceandEngineering,