低碳低合金钢临界-亚临界退火材料综合塑性研究  

Study on Integrated Plasticity of Low-carbon Low-alloy Steel During Intercritical Annealing Followed by Subcritical Annealing

作　　者：赵茂俞[1,2] 陈乾旺[1] 

机构地区：[1]中国科学技术大学化学与材料科学学院,安徽合肥230026 [2]合肥学院机械工程系,安徽合肥230022

出　　处：《热加工工艺》2012年第18期177-179,183,共4页Hot Working Technology

基　　金：安徽省教育厅自然科学研究重大项目(KJ2011ZD09);合肥学院引进人才科研启动基金资助项目(10RC02)

摘　　要：均匀细化的铁素体和细小片状珠光体晶粒是低碳低合金综合塑性显著的关键,而合理的热处理退火工艺参数能获得塑性良好的微观组织。以低碳低合金钢20CrMnTi为研究对象,在临界-亚临界温度Ac附近加热和保温处理材料。在此基础上,通过拉伸、硬度实验测试获得材料的综合塑性(硬度、伸长率、断面收缩率和屈服强度)。应用扫描电镜测试材料微观组织,研究细化的铁素体基体、细小片状渗碳体晶粒的分布。通过X射线衍射谱线可知,退火材料与原材料的铁素体相均以α-Fe形式存在,通过拉伸应力-应变曲线可知,退火材料屈服强度降低,通过试样拉伸断口的韧窝形貌图和数量可知,退火材料韧性迅速增加。最终实验结果表明,均匀细化的铁素体和细小片状珠光体有利于低碳低合金钢综合塑性变形的潜能发挥。Even finer ferrite and small thinner pearlite grains were key factors to the material obvious integrated plasticity of low carbon low alloy steel,and the materials microstructure could be attained with the suitable annealing process parameters.Low carbon low alloy steel 20CrMnTi was heated and held for a period of time near Ac temperature.Then,the integrated plasticity（hardness,elongation,section shrinkage and yield strength） experiment data were acquired with tensile,hardness tests.Furthermore,the microstructure morphologies of even finer ferrite and small thinner pearlite were tested by SEM.Ferrite phase of annealed material is the same as raw materials existing in α-Fe substantiated by XRD.The yield strength decreases,and the toughness nests and its quantity of the annealing material increase rapidly.Finally,the experiments prove that even finer ferrite and small thinner pearlite grains are feasible to exert material integrated plasticity.

关 键 词：退火 细化铁素体 片状珠光体 塑性 韧窝形貌 

分 类 号：TG156.2[金属学及工艺—热处理]