OPTIMIZATION OF HEAT TREATMENT PROCESS OF HIGH STRENGTH WDL 690D STEEL
Before being subjected to water quenched,16mm WDL690D steel was heated at 910℃,930℃,950℃and 970℃for 20min,40min and 60min,respectively.Microstructures of these samples after heat treatment were observed by optical microscopy and SEM.Rather uniform and fine martensitic laths could be observed from the samples which were heated at 950℃ for 40min and then water quenched.And then the samples with fine structure were tempered at 600℃,640℃,and 680℃for 50min,80min,100min,and 120min and then air cooling,respectively.The tensile properties at room temperature,and impact properties at different temperatures of the tempered samples at different heat treatment process parameters were measured.The metallography and SEM results showed that fairly uniform microstructure without obvious coarsening grain could be found from the samples tempered at 640℃for 80min.Moreover,the samples tempered at 640℃for 80min exhibited rather high hardness,strength,ductility and toughness properties,which had an excellent combination of strength and toughness.Based on all the results,the optimal parameters of heat treatment for WDL690D steel were determined to be heated at 950℃for 40min then water quenched and tempered at 640℃for 80min,which resulted in the finest microscopic structure and the best mechanical properties of the steel.
WDL690D steel heat-treatment optimization microstructures properties
Wang Zhiwu Ju Guangyu Hu Ningyin Gong Xueting
School of Power and Mechanical Engineering,Wuhan University,Wuhan 430072,China
国内会议
杭州
英文
395-401
2015-11-11(万方平台首次上网日期,不代表论文的发表时间)