基于熱力學數(shù)據(jù)對鈦微合金鋼TiN高溫沉淀的統(tǒng)計分析計算

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中圖分類號:TG142.33 文獻標志碼:A 文章編號:1672-0105(2025)02-0064-04
Statistical Analysis and Calculation ofHigh-temperature Precipitation of TiN in Titanium Microalloy Steel Based on Thermodynamic Data
PENG Xiying', CUI Yan2, XU Xianglai2 (1.TangshanPolytechnicUniversity,Tangshan O63299,China;2.TangshanNormalUniversity,Tangshan06309,China)
Abstract:Basedontheanalysis andcalculationof physicalchemistryphase and thermodynamicdata,the high-temperature precipitationbehavioroftitaniummicroaloyedsteelwasstudied.Itwasfoundthatthehigh-temperatureprecipitatesin Titanium-microalloyed steels predominantly consist of TiN and Ti4C2S2 phases.Liquid-phase precipitated TiN particles exhibit limited quantity and coarse dimensions,typically ranging from submicron-scale ( 100-1000nm )to micron-scale (>1μm) . In contrast,thesolid-phase precipitationofTiismoreabundant,withsizesrangingfrom100to0Onanometers.AdditionallyTiC particles havearelativelylowprecipitationtemperatureandsizesrangingfromafewtotensofnanometers.Furthermore,it was observedthatincreasing thetitanium(Ti)andnitrogen (N)content leadstoa higherproportionofcoarse liquid-phase TiN precipitation. However, when the Ti and N content is low, the formation of liquid-phase TiN can be avoided. The theoretical calculationsindicatethatwhentheNcontentisfixed,tereexistsaciticalvalueofTicontentBelowtiscriticalvalue,itanavoid thedetrmentaleffectofcoarseliquid-phaseTiNformationonductility.Controlling theTicontent withintherangeof0.1to 0.12wt% and the N content below or equal to 0.0035wt% can effectively suppress the liquid-phase precipitation of TiN while ensuring an adequateamountofTiCprecipitationforstrengtheningefects.Moreover,duringthehomogenizationprocesofthebilet,the coarsening rate of TiN is slow,and its influence on the particle size can be neglected.
Keywords: precipitation; TiN; liquid-phase precipitation; solid-phase precipitation
0引言
Ti微合金化鋼中存在TiN、 Ti4C2S2 和TiC等大量沉淀物[1-2],其形成貫穿連鑄到卷取各階段[3-7: ① 連鑄和冷卻階段TiN和 Ti4C2S2 的液析及固相析出;
② 精軋階段TiC的形變誘導(dǎo)析出; ③ 層流冷卻階段TiC的相間析出; ④ 卷取緩冷階段TiC在鐵素體中的過飽和析出。(剩余4477字)