搜索
200510October2005ResearchonIron&Steel5146No.5Sum146121.1100042.130062LFGCahnScheilTG335.11A1001-1447200505-0018-05RESEARCHONDEFORMEDAUSTENITETRANSFORMATIONDURINGCONTROLLED-COOLINGPROCESSZHULi-juan1LUYi21.TheStateKeyLabofRollingTechnologyandAutomationNortheasternUniversityShenyang110004China2.TechnologyandQualityDepartmentChangchunRailwayVehiclesCo.Ltd.Changchun130062ChinaSynopsisApredictionmodelofphasetransformationfromthermo-deformedaustenitetoferritepearliteandbainiteisgiveninthispaper.Themodelwasdevelopedonthethermodynamicbasisofsuper-elementandLFGmodelsandthekineticbasisofCahnstransformationtheoryandScheilssuperpositionrule.Theeffectsofdeformationcoolingrateandfinishrollingtemperatureonphasetransformationarediscussedinthispaper.Keywordsaustenitetransformationpredictionmodeldeformationcoolingratefinishrollingtemperature8632001AA3390301979-TRIP.1LFGCahnScheil2Fe-ΣXi-CXi=SiMnNiCrFe-ΣXiSSuperelementSFe-C2.1/C81xγ/αC1RTlnaγ/αS=ΔGγ→αS-Δµd1RTaSSΔGγ→αSSγ→αΔµdγΔGγ→αSΔµdΔGγ→αS=141ΣxiΔTiM-ΔTiNM+20853.06-466.35T-0.046304T2+71.147TlnT2Δµd=12µb2ρVγ3xiiΔTiMΔTiNMµµ=7.0×1010N/m2bb=2.5×10-10mρVγVγ=6.68×10-6m3/molα/γCxα/γC43ln3-4xα/γCxα/γC+4lnδα/γC-3+5xα/γCδα/γC+3-5xα/γC-5ln1-2xγ/αCxγ/αC-6lnδγ/αC-1+3xγ/αCδγ/αC+1-3xγ/αC=Δ-Hγ-Δ-Hα-Δ-SXSγ-Δ-SXSαTRT+6Wγ-4Wα+ΔµdRT4LFGΔGγ→α+γ1=RTxγClnaγ/αCaγC+1-xγClnaγ/αSaγS52.2γ/cemCxγ/cemC6715ln1-xγ/cemC1-2xγ/cemC+18ln1-2Jγ+4Jγ-1xγ/cemC-δγ/cemC2Jγ2xγ/cemC+5ln1-2xγ/cemCxγ/cemC+6lnδγ/cemC-1+3xγ/cemCδγ/cemC+1-3xγ/cemC=3ΔGγ→αS+ΔGcem-Δµd-Δ-HγRT+Δ-SXSγT-6WγRT6ΔGγ→α+cem=1-xγCΔGγ→αS+XγCΔGcem-Δ-Hγ+Δ-SXSγT-6Wγ-RTxγC5ln1-2xγCxγC+6lnδγ-1+3xγCδγ+1-3xγC-RT1-xγC5ln1-xγC1-2xγC+6ln1-2Jγ+4Jγ-1xγC-δγ2Jγ2xγC-1-Δµd72.3ΔGγ→α+γ'=0Ae3ΔGγ→α+cem=0Ae1Bhadeshia89ΔGFΔFN=3.25T-273-21808ΔGγ→α'F2=-6009ΔGγ→α'xα=xγΔGγ→α'=1-xγCΔGγ→αFe+RTxγClnaαCaγC+1-xγClnaαSaγS-Δµd103ScheilΣΔtj/τi=1τi91Δti11τTAde3-Ar3ΔTτT=AexpQ/RTAde3-Ar3m11AQmAde3Ar33.1γ→αΔXFΔtnαΔXF=4π31/4IFSdγ1/4GF3/4ln11-XF3/41-XFΔt12nα=∫tC0SdγIS1-XF1dt13Sdγ=24/πd00.491eε+0.155e-ε+0.143e-3ε14IFGFXFSdγd0εtCdα1=6XF1πnα1/315γ→αΔXF=K1SdγGF1-XFΔt16Δdα2=∫tecGF1-XF1-XF2dt17K18.933×10-12exp21100/Tteγ→αγ→ααdα=dα1+dα2183.2AcmΔXP=K4SγGP1-XP-XtotalFΔt19K43×103GPGP=ΔTDxγ/αC-xγ/cemC203.3123ΔXB=K5SγGB1-XB-XtotalF-XtotalPΔt21K54×104exp3431.5/TGB44.1Δµd52.6J/molΔµd=0121024.23423433CCT45～8℃/s4.35656800～840℃564.478127851Cahn236℃/s4820℃52004-12-02922