连续退火冷却速率对热镀锌双相钢DP780屈服平台的影响

来源期刊：钢铁2010年第5期

论文作者：鲍成人 李众 谭谨峰 邸洪双 潘恩宝

文章页码：81 - 83

关键词：冷却速率； 热镀锌双相钢； 屈服平台； 可动位错

Key words：cooling rate； continuous galvanizing dual phase steel； yield point elongation； movable dislocation

摘    要：采用光亮连续退火模拟试验机研究了热镀锌双相钢DP780在连续退火中不同冷却速率对其组织和屈服现象的影响。试验结果表明:随着冷却速率的提高,组织中马氏体含量增加,晶粒尺寸减小。当冷速低于12℃/s时,应力应变曲线出现屈服平台;当冷速大于12℃/s时,应力应变曲线呈现连续屈服。冷速12℃/s为该钢种出现屈服平台的临界冷却速率。

Abstract: With bright continuous annealing simulator,the microstructure and yield phenomenon of continuous galvanizing DP780 steel treated with different cooling rates were investigated.The results show that fraction of martensite increases and the size of gains decreases with increasing cooling rate.When the cooling rate is below 12℃/s,the curves of stress-strain of tested steel shows yield point elongation;when cooling rate is above 12℃/s,the curves shows no yield point elongation.Thus,the cooling rate of 12℃/s is the intercritical cooling rate for obtaining yield point elongation of the continuous galvanizing DP780 steel.