等温淬火球墨铸铁热处理工艺研究  

Investigation on Heat Treatment Process of Austempered Ductile Iron

作　　者：田迎新 曾维和[2] 刘金林 翟柏顺 王建生 曾小勤[2] 

机构地区：[1]上海圣德曼铸造有限公司,上海201805 [2]上海交通大学材料科学与工程学院,上海200240

出　　处：《热加工工艺》2016年第24期244-248,252,共6页Hot Working Technology

摘　　要：系统研究了等温淬火温度和等温时间对传统单步和两步等温淬火工艺处理的等温淬火球墨铸铁（Austempered Ductile Iron,ADI）显微组织与力学性能的影响。结果表明在280~380℃等温淬火时,随温度升高和时间延长,贝氏体组织逐渐粗化;随等温温度升高,残余奥氏体含量及其含碳量越多。等温淬火温度对ADI力学性能有显著影响,通过调整等温淬火温度可以获得不同力学性能等级的ADI。与传统单步ADI相比,两步工艺等温淬火ADI贝氏体组织更细小,残余奥氏体体积分数和残余奥氏体碳含量更高。两步等温淬火工艺能有效提高ADI抗拉强度和屈服强度,但不利于伸长率和冲击韧性提升。The influences ofaustempering temperature and anstempering time on microstructure and mechanical properties of conventional single step ADI（Austempered Ductile Iron） and two step processing ADI were investigated. The results show thatwhen the austempering is carried out at 280-380℃, the bainite microstructure becomes coarser with the increase of austempered temperature and time. The volume fraction and carbon content of retained austenite increase with austempered temperature increasing. The austempering temperature has significant influence on mechanical properties of ADI, and different mechanical properties grade of ADI can be obtained by adjusting the temperature of the austempering temperature. Compared with conventional single step ADI, two-step process ADI has finer bainite microstructure, higher volume fraction of retained austenite and higher carbon contents. Two-step austempering process can effectively improve tensile and yield strength of ADI but it is harmful to elongation and impact toughness.

关 键 词：等温淬火球墨铸铁 热处理工艺 显微组织 力学性能 

分 类 号：TG156.3[金属学及工艺—热处理]