热处理对高铬铸铁硬度与冲击韧性的影响

Effects of Heat Treatment on Hardness and Impact Toughness of High Chromium Cast Iron

利用金相显微镜、显微硬度计、冲击试验机等,探究不同淬火温度、回火温度以及铸件取向对高铬铸铁的硬度和冲击韧性的影响。结果表明:不同淬火温度、回火温度以及铸件取向影响高铬铸铁的硬度和冲击韧性。将高铬铸铁加热到1030℃保温2 h后空冷,之后经330℃回火处理,其硬度值可达到62 HRC,冲击韧性可以达到10.5 J/cm2,高铬铸铁可以获得良好的综合力学性能;同时发现,高铬铸铁铸件在与浇道平行方向上的冲击韧性普遍比与浇道垂直的方向上的冲击韧性高出14.29%~53.84%,在冲击韧性方面表现出各向异性。

The effects of different quenching temperature,tempering temperature and casting orientation on the hardness and impact toughness of high chromium cast iron were investigated by means of metallographic microscope,microhardness tester and impact tester.The results show that different quenching temperature,tempering temperature and casting orientation affect the hardness and impact toughness of high chromium cast iron.When the high-chromium cast iron is heated to 1030℃for 2 h,air cooling,and then tempered at 330℃,the hardness value of the high-chromium cast iron can reach 62 HRC,and the impact toughness can reach 10.5 J/cm2,the high-chromium cast iron can obtain good comprehensive mechanical property.At the same time,it is found that the impact toughness of high chromium cast iron casting in the direction parallel to the runner is 14.29%-53.84%higher than that in the direction perpendicular to the runner,and the impact toughness of high chromium cast iron casting is anisotropy in terms of impact toughness.