高锰系奥氏体热作模具钢时效过程中的内耗研究  

Study on Internal Friction of Ageing Process of High Mn Austenite Hot Work Tool Steel

作　　者：闵娜[1] 薛厂[1] 佟倩[1] 汪宏斌[1] 吴晓春[1] 

机构地区：[1]上海大学材料科学与工程学院,上海200072

出　　处：《上海交通大学学报》2010年第5期621-623,627,共4页Journal of Shanghai Jiaotong University

基　　金：国家科技支撑计划课题项目

摘　　要：研究了高锰系奥氏体热作模具(SDHA)钢时效过程中的内耗特性,并结合JMA方程分析了其时效动力学过程.结果表明,在时效过程中,SDHA钢在高温区域的内耗峰高度较其固溶态时有所降低,且峰宽变窄.这是由于时效过程中固溶于奥氏体间隙中的C发生了重新分配而使基体合金成分降低的缘故.在720°C等温阶段,SDHA钢内耗随保温时间的增加而增大;而在550°C等温过程中,其内耗随等温时间增加而降低.在低温时效初期,SDHA钢的间隙原子主要从奥氏体基体向界面及缺陷处扩散聚集;而在高温时效过程中,间隙C与奥氏体基体中固溶合金原子形成碳化物,并以缺陷处为核心而形核长大.The investigation on the ageing of austenite hot work tool steel by internal friction shows that the height of the peak dumps and the width of the peak narrows after ageing at 720 ℃×2 h and 550 ℃×10 h,compared with before ageing. The result reveals that the carbon atoms which are solved in the austenite lattice are repartitioned during aging,and the content of the alloy in the austenite matrix phase reduces.By analyzing the kinetic age combining JMA equation shows that at the beginning of the low temperature aging,there is a planar flow of interstitial atoms from the austenite lattice to interface and defect,while during the high temperature aging process,the interstitials and the solved alloy atoms in austenite lattices form carbide and grow centered on the defects.

关 键 词：高锰系奥氏体热作模具钢 内耗 间隙原子 时效动力学 

分 类 号：TG115.24[金属学及工艺—物理冶金]