2Cr13不锈钢表面固相渗碳后的组织与性能

Microstructure as well as Wear Resistance and Corrosion Resistance of Solid Carburized Coating on 2013 Stainless Steel

传统的固相渗碳法渗速慢,加入催渗剂会产生阻挡层,且渗层质量不易控制。常用的渗碳工艺如离子渗、气体渗和盐溶渗均存在一些不足。采用一种新型固相渗碳方法用灰口铸铁HT300中的片状石墨对2Cr13不锈钢进行表面改性,用XRD、SEM、微观硬度计、ML-100干式销盘两体磨料磨损试验机等分析了新型固相渗碳层的物相组成、微观组织、微观硬度和耐磨性,使用CS350电化学工作站测试了其耐蚀性能。结果表明:在1120℃保温10h,850℃保温1h条件下固相渗碳,可在2Cr13不锈钢表面原位生成碳化铬颗粒。原位反应层主要分为两个区域:晶界碳化物细小断续区和晶界碳化物粗大连续区,显微硬度呈梯度分布,最高可达1082HV1N。渗碳后表层耐磨性提高了4倍,耐蚀性能有所下降。

A novel solid- phase carburizing method was adopted to modify the surface of 2Crl 3 stainless steel by use of flaky graphite in gray iron HT300.The phase species and microstructure of asobtained carburizing coating were analyzed by X- ray diffraction and scanning electron microscopy.A microhardness meter and an ML-100 pin- on- disc two body abrasive wear tester were performed to evaluate the microhardness and wear resistance of the carburizing coating;and a CS350 electrochemical workstation was conducted to evaluate the corrosion resistance of the carburizing coating.Results indicated that,when the stainless steel substrate subjected to carburizing was held at 1 120 ℃ for 10 h,in association with holding at 850 ℃ for 1 h,CrC grains could be in-situ generated on the steel surface.Two regions could be classified in as-formed in- situ reaction layer;discontinuous region of small grain boundary carbides and continuous region of coarse grain boundary carbides.The microhardness of the carburizing coating exhibited gradient distribution,with the maximum value being as much as 1 082 HV_(1N).In the meantime,carburizing led to greatly increased wear resistance of the stainless substrate but decreased corrosion resistance to some extent.