奥氏体化温度和时间对Cr5钢组织和性能的影响  

Influence of Austenitizing Temperature and Time on Microstructure and Properties of Cr5 Steel

作　　者：岳慎伟 刘瑞莉 王文焱[1] 袁海伦 岳宗格 

机构地区：[1]河南科技大学材料科学与工程学院,河南洛阳471023 [2]中信重工机械股份有限公司,河南洛阳471003

出　　处：《河南科技大学学报（自然科学版）》2014年第1期4-8,2,共5页Journal of Henan University of Science And Technology:Natural Science

基　　金：河南省重大科技攻关基金项目(6020091020132-1)

摘　　要：运用扫描电子显微镜、X射线衍射仪、金相软件和洛式硬度计,对Cr5钢组织进行了观察、物相(淬火前后)分析、碳化物含量的计算和硬度测试。研究结果表明:Cr5钢中碳化物相主要是Cr7C3、Cr23C6和Cr3C2相,其形貌特征有球状、椭球状和棒状,并且无规律地分布于基体上;淬火后碳化物部分溶入基体,未溶碳化物以细小颗粒状分布于马氏体上;碳化物的溶解量随温度的升高和保温时间的延长而增加,970℃时,碳化物大部分溶解;保温开始阶段,碳化物溶解速率较快,随时间的延长溶解速率减慢,超过60 min时,溶解速率趋于零;Cr5钢硬度随加热温度的升高和保温时间的延长先增加后降低,970℃加热保温60 min硬度达到峰值,为55.4HRC。The microstructure,phase( before and after quenching),carbide content and hardness were observed,analyzed,calculated and tested by means of scanning electron microscopy,X-ray diffraction,optical software and Rockwell hardness tester respectively. The results show that the phases of carbides in Cr5 steel are mainly Cr 7 C 3,Cr 23 C 6 and Cr 23 C 6. Their morphology characteristics are spherical,ellipsoidal and rod irregularly distributed in the matrix. After quenching most of carbides are dissolved in the matrix,and the carbides of not dissolving with small particles are distributed in the martensite. The dissolution amount of carbides increase with the increase of temperature and soaking time. Carbides are mostly dissolved into matrix when temperature is 970 ℃. At the early soaking stage,carbides dissolve rapidly,but dissolution rate decreases with the soaking time prolongating,and finally tends to zero when soaking time exceed 60 min. The hardness of Cr5 steel increases and then decreases with the increase of temperature and soaking time. The peak hardness 55. 4HRC is reached after quenching at 970 ℃ for 60 min.

关 键 词：Cr5钢 淬火温度 保温时间 微观组织 硬度 

分 类 号：TG156.1[金属学及工艺—热处理]