耐老化马氏体时效不锈钢纳米析出相和逆变奥氏体调控研究进展  

Research Progress on the Control of Nano-precipitated and Reversed Austenite in Thermal Aging Resistant Maraging Stainless Steel

作　　者：吕润涛 周张健[1] 白冰[2] 杨文[2] LYU Runtao;ZHOU Zhangjian;BAI Bing;YANG Wen(School of Materials Science and Engineering,University of Science&Technology Beijing,Beijing 100083,China;China Institute of Atomic Energy,Beijing 102413,China)

机构地区：[1]北京科技大学材料科学与工程学院,北京100083 [2]中国原子能科学研究院,北京102413

出　　处：《材料导报》2024年第4期151-157,共7页Materials Reports

基　　金：国家自然科学基金(52001330)。

摘　　要：马氏体时效不锈钢通过中温时效可析出高数密度超细纳米级析出相,使其获得高强度和一定的韧性。但是,当马氏体时效不锈钢在中低温下长期服役时,由于富Cu相、NiAl相等析出强化相的粗化及Fe-Cr基体调幅分解形成脆性富Cr相等,其延展性和冲击性能大幅降低,出现明显的热老化脆化问题,给服役安全性带来隐患。通过适当降低铬含量和析出元素含量、提高镍含量可有效抑制析出强化相的粗化及脆性相的析出。若进一步通过成分设计和热处理调控获得适量的逆变奥氏体,可望有效改善其热老化脆化问题。本文介绍了马氏体时效不锈钢的成分设计原则、析出相特点及其热稳定性对热老化脆化的影响,综述了有利于提高组织热老化稳定性的马氏体时效不锈钢中纳米析出强化相和逆变奥氏体的调控方法,为新型耐老化马氏体时效不锈钢的成分设计和制备提供参考。Maraging stainless steels achieve ultra-high strength,high toughness and excellent corrosion resistance by precipitating of ultra-fine nanoscale strengthen phases formed by short time intermediate aging,which can be used in nuclear energy,aerospace and other high-tech fields.However,when it works for a long time at medium and low temperature,its ductility and impact properties will be reduced sharply due to the coarsening of precipitation strengthening phases such as Cu rich phase and NiAl,as well as the formation of brittle Cr rich phase due to the amplitude modulation decomposition of Fe-Cr matrix.This obvious thermal aging and embrittlement problems leads to a hidden danger for service safety.It is important to reduce the coarsening of precipitated phases and the forming of brittle phases through optimal composition design and heat treatment,such as reducing the chromium and precipitated element content,increasing the nickel content.Furthermore,it is reported that reversed austenite can improves the plastic toughness of maraging stainless steels,which is expected to improve the thermal aging embrittlement problem.The amount of reversed austenite also can be controlled by composition design and post heat treatment.In this paper,the composition design principle and typical precipitated phase of martensite aging stainless steel are introduced.The control methods of nano precipitated strengthening phase with high thermal stability and the formation of reversed austenite in martensite aging stainless steel which are benefit for improving thermal aging resistance are focused on.It is expected that this review paper can provide a reference for the composition design and preparation of new types of aging resistant martensite aging stainless steel.

关 键 词：马氏体时效不锈钢 纳米析出相 逆变奥氏体 热老化 

分 类 号：TG142.71[一般工业技术—材料科学与工程]