低中碳Si－Mn－V钢回火马氏体脆性机理与稀土元素的作用

MECHANISMS OF TEMPERED MARTENSTIEEMBRITTLEMENT IN LOW AND MEDIUM-CARBON Si-Mn-V STEELS AND THE EFFECT OF RARE-EARTH METALS

通过冲击试验并利用透射电镜，扫描电镜和Ｘ射线衍射仪等测试设备研究了低中碳Ｓｉ－Ｍｎ－Ｖ钢回火马氏体脆性机理及稀土元素的作用，结果表明：回火碳化物的析出和粗化是导致试验钢回火马氏体脆性断裂的本质因素，回火马氏体脆性断裂方式强烈取决于钢中含碳量；稀土元素对试验钢回火马氏体脆性的影响与钢中含碳量有关．

Mechanisms of tempered martensite embrittlement in low and medium-carbon Si-Mn-Vsteels and the effect of rare-earth metals(RFM)were investigated using TEM,SEM,X-raydiffraction techniques and charpy impact testing.Results show that the precipitation andgrowth of carbides during tempering are the main factors leading to tempered martensite em-brittlement of the steel investigated.The fracture mode of tempered martensite embrittle-ment intensity depends upon the carbon containing in the steels,and the effects of REM onthe tempered martensite embrittlement are related to the carbon containing of these steels.