马氏体对C-Si-Mn冷轧双相钢屈服特性的影响

通过实验室退火与回火,采用力学测定与显微组织分析研究了马氏体体积分数与回火温度对双相钢屈服特性的影响.结果表明:随马氏体体积分数从0%增加到约15%,双相钢的屈服强度显著降低,降低值约为80～100MPa;而马氏体体积分数在15%～35%之间,双相钢的屈服强度维持在一个较低的水平.当马氏体体积分数大于35%,双相钢屈服...

Effect of Martensite on Yield Characteristics of Cold Rolled C-Si-Mn Dual Phase Steel

Based on the annealing and tempering in lab,the effect of martensite volume fraction(MVF) and tempering temperature on yield characteristics of trial dual phase(DP) steel were investigated by mechanical test and microstructure analysis.The results show that the MVF increases from 0% to about 15%,the yield stress of DP steels decreases significantly,the decrease values are between 80MPa and 100MPa;When MVF is in 15%-35%,the yield stress of DP steels maintains at a lower level,whereas,when MVF is more than 35%,the yield stress increases rapidly.When MVF exceeds 10%,the DP steels represent continuous yield.With the increasing of tempering temperature from 200℃ to 400℃,the yield stress of DP steels increases monotonously,and the yield platform reappears when tempering temperature is more than 300℃.Based on the observation and analysis to the fine microstructures of DP steels,the high density phase transformation induced dislocation and residual stress are considered as the potential reasons for the low stress and continuous yield of DP steels.