奥氏体铬锰氮不锈钢在气蚀过程中的组织变化

MICROSTRUCTURE CHANGES DURING CAVITATION EROSION FOR A CrMnN STAINLESS STEEL WITH METASTABLE AUSTENITE

用Ｘ射线衍射（ＸＲＤ）分析及透射电镜（ＴＥＭ）方法研究了一种含亚稳奥氏体的铬锰氮不锈钢在气蚀过程中的组织变化特性。结果表明，ＺＧ０Ｃｒ１３Ｍｎ８Ｎ钢气蚀前主要由α马氏体、亚稳奥氏体和少量ε马氏体组成；气蚀使表面位错密度显著增加以及平直和平面位错数量增多，同时诱发γ→ε、ε→α及γ→α转变；气蚀过程中应变诱发出的ε和α马氏体更趋于在高位错密度区域形成。

The characteristics of microstructure changes during cavitation erosion (CE) were investigated by use of XRD and TEM analyses for a CrMnN stainless steel (0Cr13Mn8N) with metastable austenite. The results show that before CE the microstructure of the surface layer of specimens is consisted of α martensite, metastable austenite and ε martensite, during CE the microstructure changes are as follows: the dislocation density, quantity of straight and planer dislocations are increased, and γ→ε、ε→αand γ→α martensitic transformations are induced. The CE induced ε and α martensites are nucleated more frequently in the region of higher dislocation density.