轧制工艺对D6A钢微观组织和力学性能的影响

为了研究轧制工艺对D6A钢组织及力学性能的影响,分别制备了87％和93％压下量的D6A钢,并通过EBSD和拉伸性能测试进行了分析.结果表明,随轧制压下量由87％增加至93％,D6A钢中晶粒尺寸显著减小,由5 μm减至1 μm,小角度晶界含量则大幅增加,由55％增至80％.随轧制压下量的增加,D6A钢的抗拉强度及屈服强度...

Effect of rolling process on microstructure and mechanical properties of D6A steel

In order to study the effect of rolling process on the microstructure and mechanical properties of D6A steel,D6A steel with 87%and 93%rolling reduction were prepared in this study.The effect of rolling process on the microstructure and mechanical properties of D6A steel was analyzed by EBSD and tensile tests.The results show that,as the rolling reduction increased from 87%to 93%,the grain size of D6A steel significantly decreased from 5μm to 1μm,and the content of low angle grain boundary increased from 55%to 80%.With increasing the rolling reduction,the tensile strength,and the yield strength increased from 1175 MPa to 1245 MPa,and from 1010 MPa to 1195 MPa,respectively,whereas the elongation decreased from 19%to 17%.Meanwhile the work hardening rate curves of the two kinds of steel were plotted.An increase in the rolling reduction causes an increase in both the tensile and the yield strength of D6A steel due to the grain and sub-grain refinement,and a decrease in the tensile plasticity due to the insufficient storage capacity of the dislocations in small grain and sub-grain,thereby leading to the premature necking during the tensile process.