16Cr-2.5Mn高铬白口铁的亚临界热处理研究  

Study on the sub-critical heat treatment of 16Cr-2.5Mn high chromium white iron

作　　者：孙志平[1] 左汝林[2] 李聪[3] 高升吉[1] 沈保罗[1] 闫静[1] 杨林[1] 黄四九 

机构地区：[1]四川大学金属材料系 [2]重庆大学材料学院,四川重庆400044 [3]中国核动力研究设计院核燃料及材料国家重点实验室,四川成都610041 [4]双流县四久稀土合金铸造厂,四川双流610211

出　　处：《材料科学与工艺》2006年第5期510-513,共4页Materials Science and Technology

摘　　要：研究了亚临界热处理对16Cr-2.5Mn高铬白口铁组织转变和性能的影响,并利用TEM、SEM、XRD和M200磨损试验机分析了其硬化机制和对耐磨性的影响.研究表明:过饱和奥氏体中固溶的Cr和C在亚临界热处理时会以(Cr,Fe)23C6形式析出,残余奥氏体发生了马氏体相变,使合金产生二次硬化;亚临界热处理中,保温时间过长,将导致(Cr,Fe)23C6向M3C原位转变发生,基体组织发生珠光体转变,导致硬度和耐磨性能不同程度降低;残余奥氏体含量为10%左右时,合金获得最高硬度和最佳耐磨性能.The effect of sub-critical heat treatment on microstructure and properties of 16Cr- 2.5Mn high chromium white iron are studied in this paper. The hardening mechanism and abrasion resistance are analyzed by using transmission electron microscopy （TEM）, scanning electron microscopy （SEM）, X- ray diffraction （XRD） and M200 wear test machine. Results show that Cr and C solid-dissolved in the supersaturated austenite precipitate as （Cr, Fe）23 C6. Thereby the retained austenite transforms into martensite in cooling process which results in secondary hardning. Long holding time would cause in situ transformation of （ Cr, Fe） 23 C6 to M3C carbides in the process of sub-critical treatment and the matrix transforming to pearlitic structure, Which would cause hardness and abrasion resistance decreasing. The alloy would obtain the highest hardness and optimal abrasion resistance when the content of retained austenite is 10%.

关 键 词：亚临界热处理 二次硬化 耐磨性 TEM 

分 类 号：TG143[一般工业技术—材料科学与工程] TG172[金属学及工艺—金属材料]