形变及冷却条件对35钢铁素体组织的影响

来源期刊：钢铁2009年第7期

论文作者：黄源慧 陈颖 陈其安 刘雅政

文章页码：76 - 80

关键词：35钢； 缓慢冷却； 晶粒细化； 超平衡数量铁素体

Key words：steel 35； slow cooling； grain refinement； over-equilibrium amount ferrite

摘    要：利用热模拟单道次压缩形变试验研究了35钢在临界奥氏体区(Ae₃～Ar₃)形变后铁素体组织的变化规律。结果表明,形变后水淬,小形变时铁素体首先在原奥氏体晶粒的界隅和晶界上形核,随着形变温度的降低和应变量的增大,原奥氏体内部出现大量细小、等轴的铁素体。在此温度区间形变后缓慢冷却,能够得到超平衡数量(共析转变温度的铁素体转变量)的铁素体,并且随形变温度的降低和形变量的增大,铁素体晶粒明显细化和等轴化。当形变温度降到690℃(Ar₃附近),真应变0.92时,铁素体晶粒细化到2～4μm,其体积分数达到76.86%。

Abstract: The ferrite structure evolution of undercooled austenite(Ae₃-Ar₃)of steel 35 after deformation has been investigated by means of hot compression simulation experiment.It shows that the fine-grain ferrite forms along the austenite boundaries under the condition of small deformation after water quenching.There are also smaller ferrite grains in intragranular position with the decreasing deformation temperature and the increasing strain.The over-equilibrium amount of ferrite can be obtained by deformation and subsequently slow cooling among the above mentioned temperature range.The ferrite grain size is fined to 2-4 μm and the volume fraction is about 76.86% after heavy deformation(0.92)under lower temperature(690 ℃).