文献类型：期刊文献

中文题名：Heat Treatment Effect on Microstructure, Hardness and Wear Resistance of Cr26 White Cast Iron

英文题名：Heat Treatment Effect on Microstructure, Hardness and Wear Resistance of Cr26 White Cast Iron

作者：Zhou Shaoping[1];Shen Yehui[1];Zhang Hao[2];Chen Dequan[2]

机构：[1]E China Univ Sci & Technol, Minist Educ, Key Lab Pressure Syst & Safety, Shanghai 200237, Peoples R China;[2]Shanghai First Fluid Machinery Co Ltd, Shanghai 201709, Peoples R China

年份：2015

卷号：28

期号：1

起止页码：140

中文期刊名：Chinese Journal of Mechanical Engineering

外文期刊名：CHINESE JOURNAL OF MECHANICAL ENGINEERING

收录：CSTPCD;;EI(收录号：20150600487823);Scopus;WOS:【SCI-EXPANDED(收录号:WOS:000347667200016)】；CSCD:【CSCD2015_2016】；

基金：Supported by National Hi-tech Research and Development Program of China(863 Program, Grant No. 2013BAF01B01)

语种：英文

中文关键词：Cr26 white cast iron;heat treatment;microstructure;hardness;wear resistance

外文关键词：Cr26 white cast iron; heat treatment; microstructure; hardness; wear resistance

摘要：High chromium cast iron（HCCI） is taken as material of coal water slurry pump impeller, but it is susceptible to produce serious abrasive wear and erosion wear because of souring of hard coal particles. The research on optimization of heat treatments to improve abrasive wear properties of HCCI is insufficient, so effect of heat treatments on the microstructure, hardness, toughness, and wear resistance of Cr26 HCCI is investigated to determine the optimal heat treatment process for HCCI. A series of heat treatments are employed. The microstructures of HCCI specimens are examined by using optical microscopy and scanning electron microscopy. The hardness and impact fracture toughness of as-cast and heat treated specimens are measured. The wear tests are assessed by a Type M200 ring-on block wear tester. The results show the following： With increase of the quenching temperature from 950 ℃ to 1050 ℃, the hardness of Cr26 HCCI increased to a certain value, kept for a time and then decreased. The optimal heat treatment process is 2 h quenching treatment at 1000 ℃, followed by a subsequent 2 h tempering at 400 ℃. The hardness of HCCI is related to the precipitation and redissolution of secondary carbides in the process of heat treatment. The subsequent tempering treatment would result in a slight decrease of hardness but increase of toughness. The wear resistance is much related to the ＂supporting＂ effect of the matrix and the ＂protective＂ effect of the hard carbide embedded in the matrix, and the wear resistance is further dependent on the hardness and the toughness of the matrix. This research can provide an important insight on developing an optimized heat treatment method to improve the wear resistance of HCCI.
High chromium cast iron(HCCI) is taken as material of coal water slurry pump impeller, but it is susceptible to produce serious abrasive wear and erosion wear because of souring of hard coal particles. The research on optimization of heat treatments to improve abrasive wear properties of HCCI is insufficient, so effect of heat treatments on the microstructure, hardness, toughness, and wear resistance of Cr26 HCCI is investigated to determine the optimal heat treatment process for HCCI. A series of heat treatments are employed. The microstructures of HCCI specimens are examined by using optical microscopy and scanning electron microscopy. The hardness and impact fracture toughness of as-cast and heat treated specimens are measured. The wear tests are assessed by a Type M200 ring-on block wear tester. The results show the following: With increase of the quenching temperature from 950 degrees C to 1050 degrees C, the hardness of Cr26 HCCI increased to a certain value, kept for a time and then decreased. The optimal heat treatment process is 2 h quenching treatment at 1000 degrees C, followed by a subsequent 2 h tempering at 400 degrees C. The hardness of HCCI is related to the precipitation and redissolution of secondary carbides in the process of heat treatment. The subsequent tempering treatment would result in a slight decrease of hardness but increase of toughness. The wear resistance is much related to the "supporting" effect of the matrix and the "protective" effect of the hard carbide embedded in the matrix, and the wear resistance is further dependent on the hardness and the toughness of the matrix. This research can provide an important insight on developing an optimized heat treatment method to improve the wear resistance of HCCI.