奥氏体化条件对675装甲钢中马氏体相变的影响  

Effect of Austenitization Condition on the Martensitic Transformation in 675 Armor Steel

作　　者：乔志霞[1] 李连进[1] 宁保群[2] 

机构地区：[1]天津商业大学机械工程学院,天津300134 [2]天津理工大学材料学院,天津300191

出　　处：《材料工程》2014年第7期5-9,共5页Journal of Materials Engineering

基　　金：国家自然科学基金钢铁联合基金(50834011);国家自然科学基金项目(51204121;51104107)

摘　　要：利用高分辨热膨胀仪,结合显微组织分析,研究了奥氏体化过程中奥氏体化加热温度和保温时间两个重要参数对675装甲钢快速冷却中马氏体相变的影响,包括原奥氏体晶粒尺寸、马氏体显微组织形态和马氏体相变点(Ms)。结果表明:奥氏体化温度对原奥氏体晶粒尺寸的影响程度远大于保温时间;奥氏体化过程中,675装甲钢中钒微合金碳化物(V4C3)在大约1000℃能全部溶入到奥氏体中,从而失去钉扎奥氏体晶界的作用,致使晶粒开始粗化;随原奥氏体晶粒尺寸增大,快速冷却得到的马氏体尺寸迅速增大,表现出对原奥氏体晶粒的组织遗传现象;马氏体相变点(Ms)受到奥氏体晶粒尺寸和钒微合金碳化物向奥氏体中溶解程度两个因素综合作用。The effect of austenitization temperature and holding time on the martensitic phase transfor-mation in 675 armor steel was investigated using a combination of high-resolution dilatometric meas-urements and microstructural analysis, including prior austenite grains size, martensite morphologyand martensitic transformation temperature （Ms）. The results show that austenitization temperaturehas much more significant effect on prior austenite grains size than holding time at austenite region.Carbides of vanadium microalloying elements can completely dissolve into austenite when the austen-itization temperature reaches about 1000℃, and thus ceases to be effective in pinning austenite grainboundaries. The length and width of martensite laths or needles increase with increasing austenitegrain size, showing apparent characteristic of hereditary. The variation of Ms temperature is a syn-thetic effect of the austenite grain size and the dissolution extent of vanadium microalloying elementsinto austenite.

关 键 词：装甲钢 奥氏体化 马氏体 奥氏体晶粒尺寸 

分 类 号：TG113.12[金属学及工艺—物理冶金]