终轧温度对钛微合金钢TiC析出硬化的作用  

Effect of finish rolling process on precipitation hardening of TiC in a titanium microalloyed steel

作　　者：王瑞 崔岩 彭喜英 冯运莉 孙新军[4] 雍岐龙[4] Wang Rui;Cui Yan;Peng Xiying;Feng Yunli;Sun Xinjun;Yong Qilong(College of Metallurgy and Energy,North China University of Science and Technology,Tangshan Hebei 063210,China;Department of Chemistry,Tangshan Normal University,Tangshan Hebei 063000,China;Tangshan Polytechnic University,Tangshan Hebei 063299,China;Research Institute of Structural Steels,Central Iron and Steel Research Institute Co.,Ltd.,Beijing 100081,China)

机构地区：[1]华北理工大学冶金与能源学院,河北唐山063210 [2]唐山师范学院化学系,河北唐山063000 [3]唐山工业职业技术大学,河北唐山063299 [4]钢铁研究总院有限公司工程用钢研究院,北京100081

出　　处：《金属热处理》2025年第2期200-206,共7页Heat Treatment of Metals

基　　金：国家自然科学基金(51974143);唐山市科技计划(23130220E);唐山师范学院校基金(2023B02)。

摘　　要：根据二元析出相的固溶析出理论和经典形核长大动力学理论,计算了Ti微合金高强钢中TiC在奥氏体(γ)中沉淀析出的形核参量,进而绘制出TiC析出-时间-温度(PTT)曲线、TiC形核率-温度(NrT)曲线;同时研究了精轧工艺对TiC形核率、TiC析出速度及强度和硬度的影响。结果表明,TiC形变诱导析出最大形核率温度为740℃、最快析出温度为820℃、最大硬度对应终轧温度为880℃;当终轧温度介于780~830℃时,TiC形变诱导析出速率受温度影响不大,对硬度几乎没有影响;当终轧温度介于830~880℃时,随终轧温度升高,TiC形变诱导析出速率及析出量均减小,促使卷取时细小TiC析出量增多,析出硬化作用增大,硬度升高;当终轧温度>880℃时,由于晶粒尺寸增大,硬度降低。Nucleation parameters of TiC precipitation in austenite(γ)in a Ti microalloyed high-strength steel were calculated according to the solid solution precipitation theory and classical nucleation growth dynamics theory of binary precipitates.Then the TiC precipitation-time-temperature(PTT)curve and TiC nucleation rate-temperature(NrT)curve were drawn.The effects of finish rolling on the TiC nucleation rate,TiC precipitation rate,strength,and hardness were also studied.The results show that the temperature of the maximum nucleation rate of deformation-induced TiC precipitation is 740℃,the fastest precipitation temperature is 820℃,and the corresponding finish rolling temperature for the maximum hardness is 880℃.When the finish rolling temperature is 780-830℃,the rate of deformation-induced TiC precipitation is not significantly affected by temperature and has almost no effect on the hardness.As the finish rolling temperature increases from 830℃to 880℃,the rate and precipitation amount of deformation-induced TiC precipitation decrease,promoting an increase in the amount of fine TiC precipitation during coiling,an increase in precipitation hardening effect,and an increase in hardness.When the finish rolling temperature is higher than 880℃,the hardness decreases due to the increase in grain size.

关 键 词：TI微合金钢 TiC析出 PTT曲线 NrT曲线 终轧温度 

分 类 号：TG142.1[一般工业技术—材料科学与工程]