摘要
将中碳低合金耐磨铸钢分别加热至880,910,930,960℃,保温2h后油淬,之后分别在210,240,260℃下回火2h;根据冲击韧性确定最佳一次回火热处理工艺后再进行240℃×2h的第二次回火处理;研究了二次回火后试验钢的性能和马氏体亚结构。结果表明:二次回火后试验钢的抗拉强度为1 820 MPa,硬度为54 HRC,冲击功为35J,实现了高强韧性和高耐磨性的良好匹配;二次回火后马氏体中的孪晶出现了回复和消失,马氏体亚结构主要为高密度位错和少量孪晶,大量的位错阻碍了裂纹扩展,提高了试验钢的强韧性。
Medium carbon low alloy wear resistant cast steel was heated to 880,910,930,960 ℃for 2hand following by oil quenching,and then tempering progresses were performed at 210,240,260 ℃ for 2h.At last,second tempering at 240 ℃for 2hwas performed after determining the best heat treatment accoding to the impact toughness.The properties and martensite substrate of the tested steel after double tempering were studied.The result show that,after double tempering,the tensile strength of the tested steel up to 1 820 MPa,the hardness was54 HRC and the impact energy was 35 J,the tested steel exhibited a good match with high strength,high toughness and good wear resistance.For the reasons of recovery and disappearance of twins in martensite after second tempering,the martensite substrate was high density of dislocations and small amounts of twins,large numbers of dislocations hindered the crack extension and improved the strength-toughness of the tested steel.
出处
《机械工程材料》
CAS
CSCD
北大核心
2015年第2期50-53 89,89,共5页
Materials For Mechanical Engineering
基金
河南科技大学科研基金资助项目(2006ZY053)
河南省杰出人才创新基金资助项目(0621000600)
关键词
中碳低合金耐磨铸钢
二次回火
力学性能
强韧性
马氏体亚结构
medium carbon low alloy wear resistant cast steel
double tempering
mechanical property
strength-toughness
martensite substrate
