冷却速度对高Cr铁素体耐热钢马氏体相变和微观组织的影响  

Influence of cooling rate on martensite transformation and microstructure of high Cr ferritic heat-resistant steel

作　　者：高秋志[1] 刘家咏[1] 刘永长[1] 邸新杰[1] 宁保群[1] 

机构地区：[1]天津大学材料科学与工程学院天津市现代连接技术重点实验室,天津300072

出　　处：《金属热处理》2012年第5期20-23,共4页Heat Treatment of Metals

基　　金：国家自然科学基金钢铁联合基金重点项目(50834011)

摘　　要：利用差分膨胀仪测定的热膨胀曲线,对高Cr铁素体耐热钢不同冷却速度下的马氏体相变进行了研究。测定马氏体相变的动力学行为并对其微观组织进行分析。结果表明,冷却速度越高,马氏体转变的起始温度和终止温度越低。当马氏体体积分数小于40%时,转变速率达到峰值。室温组织为板条马氏体+δ-铁素体,硬度值随冷速升高而升高。Martensite transformation for high Cr ferritic heat-resistant steel was researched based on dilatometric curves which were measured by differential dilatometor. The kinetics of martensite transformation and microstructure of high Cr ferritic heat-resistant steel were studied. The results indicate that the starting and finishing points of martensite transformation decrease with the increase of cooling rate. The transformation velocity reaches a peak value when martensite volume fraction is less than 40%. The microstructure is lath martensite and δ- ferrite, and the hardness increases with the increase of cooling rate.

关 键 词：高Cr铁素体耐热钢 热膨胀曲线 马氏体转变 Δ-铁素体 

分 类 号：TG142.73[一般工业技术—材料科学与工程]