摘要
使用Gleeble⁃3800热模拟试验机建立了水电用Q690CFD高强钢的SH⁃CCT曲线,研究了冷却速度对试验钢粗晶区显微组织与硬度的影响。结果表明,在所测试冷却速度下,试验钢热影响区出现了马氏体、马氏体+贝氏体与贝氏体3种转变形式。其中当冷却速度为40℃/s时,试验钢热影响区硬度达到最大,为344 HV10,组织为板条马氏体与贝氏体铁素体的混合组织。随着冷却速度的降低,热影响区组织中开始出现粒状贝氏体,基体硬度呈现逐渐减小的趋势,同时贝氏体内部的M⁃A组元也由颗粒状与短棒状转变为片状。当冷却速度低于5℃/s时,热影响区组织全部为粒状贝氏体,且基体硬度出现了低于母材的现象。
SH⁃CCT curves of Q690CFD high strength steel for hydropower were established by using Gleeble⁃3800 thermal simulation test machine,and the effect of cooling rate on the microstructure and hardness of the coarse grain heat affected zone of the tested steel was studied.The results show that three transformation forms as martensite,martensite and bainite and bainite occur in the heat affected zone(HAZ)of the tested steel at the measured cooling rate.When the cooling rate is 40℃/s,the hardness of the HAZ reaches the maximum of 344 HV10,and the microstructure is composed of lath martensite and bainite ferrite.With the decrease of cooling rate,granular bainite begins to appear,and the hardness of the matrix decreases gradually.At the same time,the shape of M⁃A component in bainite changes from granular and short rod to lamella.When the cooling rate is lower than 5℃/s,the microstructure of the HAZ is all granular bainite,and the hardness of the matrix is lower than that of the base metal.
作者
曹佳丽
靳红泽
李康立
徐亚鹏
赵强
王翠萍
李梦楠
Cao Jiali;Jin Hongze;Li Kangli;Xu Yapeng;Zhao Qiang;Wang Cuiping;Li Mengnan(Pumped-Storage Technological&Economic Research Institute State Grid Xinyuan Co.,Ltd.,Beijing 100053,China;National Center of Quality Inspection and Testing for Hydro Steel Structure Ministry of Water Resources,Zhengzhou Henan 450044,China)
出处
《金属热处理》
CAS
CSCD
北大核心
2024年第2期60-65,共6页
Heat Treatment of Metals
基金
国网新源控股技术经济研究院水电工程高强度易焊接钢板及配套焊材关键技术研究(GXYZH00KFJS2200039)。
