Effects of Destabilisation and Tempering on Microstructure and Properties of 14wt％Cr-1wt％Mo High Chromium Iron
As-cast 14wt％Cr-1wt％C-0.8wt％Mo high chromium iron was hardened by forced air cooling after destabilisation treatment at 1000 ℃ for 4 hours. After hardening, the iron was tempered for 4 hours at temperatures in the range from 300 to 600 ℃ followed by air cooling. The resultant microstructures were studied by electron microscopy and related to hardness and dry wear properties. It was found that the as-cast microstructure consisted of eutectic M7C3 carbide, primary austenite dendrites and martensite in eutectic regions. After destabilisation and air hardening the microstructure consisted of secondary carbides dispersed in a matrix of martensite and retained austenite. During tempering, the precipitation of secondary carbides within the matrix was increased and the retained austenite transformed to ferrite and carbides. Tempering in the range of 450-500 ℃ reduced the destabilised hardness and pin on disc wear tests showed that wear resistance was improved slightly by about 12-15％. Tempering at 550 ℃ reduce the hardness and wear resistance. The optimum tempering temperature for obtaining the required properties with complete decomposition of the retained austenite must be carefully controlled between 450-500 ℃.
high chromium iron heat treatment destabilisation tempering hardness wear resistance
Amporn Wiengmoon John T.H.Pearce Torranin Chairuangsri
Department of Physics,Faculty of Science,Naresuan University,Phitsanulok,65000,Thailand National Metals & Materials Technology Centre,Patumthani,12120,Thailand Department of Industrial Chemistry,Faculty of Science,Chiang Mai University,Chiang Mai,50200 Thailan
国际会议
The Fourth Asian Conference on Heat Treatment and Surface Engineering(第四届亚洲热处理及表面工程大会)
北京
英文
52-56
2009-10-27（万方平台首次上网日期，不代表论文的发表时间）