马氏体体积分数对热轧双相钢形变位错结构和断裂的影响

来源期刊：钢铁2009年第8期

论文作者：方圆 刘雅政 周乐育 宋仁伯 黄全伟

文章页码：89 - 92

关键词：热轧双相钢； 马氏体体积分数； 形变位错结构； 断裂

Key words：hot rolled dual phase steel； martensite volume fraction； deformation dislocation structure； fracture

摘    要：利用SEM、TEM研究了同一成分的热轧双相钢的马氏体体积分数对形变位错结构和断口组织特征的影响。结果表明,马氏体体积分数为20%~30%时,体积分数增加对双相钢形变位错结构的演变影响较小。且马氏体在变形的后期中将出现伴生的高位错密度区和低位错密度区。断裂时当马氏体体积分数增加到30%,颈缩提前,且微孔有向微裂纹转变的趋势。因此,马氏体体积分数为20%的双相钢的成形性能优于马氏体体积分数为30%的双相钢。

Abstract: Effect of martensite volume fraction on deformation dislocation structure and fracture for hot rolled dual-phase steel of the same composition was studied by using SEM and TEM.The results show that effect of martensite volume fraction on deformation dislocation structure of DP steel is little when martensite volume fraction is between 20% and 30%.And martensite would appear both region of high dislocation density and region of low dislocation density after deformation.Furthermore,the micropore in DP steel would change into microcrack when martensite volume fraction reached 30%.Meanwhile necking appeared early.So when martensite volume fraction was 20%,forming property of DP steel was better than the DP steel whose martensite volume fraction was 30%.