高强钢中亚稳奥氏体对断裂韧性影响的研究进展  

Research Progress on the Influence of Metastable Austenite on the Fracture Toughness of High-Strength Steels

作　　者：唐景韬 姚英杰 张游游 吴文华 李宇博 陈浩 杨志刚 TANG Jingtao;YAO Yingjie;ZHANG Youyou;WU Wenhua;LI Yubo;CHEN Hao;YANG Zhigang(Key Laboratory of Advanced Materials of Ministry of Education,School of Materials Science and Engineering,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学材料学院教育部先进材料重点实验室,北京100084

出　　处：《金属学报》2025年第1期77-87,共11页Acta Metallurgica Sinica

基　　金：国家重点研发计划项目No.2022YFE0110800;国家自然科学基金项目Nos.52201011和51922054。

摘　　要：超高强度钢中亚稳奥氏体调控是协同提升其强塑性的重要策略。亚稳奥氏体在拉伸变形过程中能够通过形变诱发马氏体相变来延迟颈缩并增强材料的加工硬化能力。在超高强度钢部件轻量化及载荷复杂化的趋势下,迫切需要进一步提升其断裂韧性,在保证强塑性的基础上,如何利用亚稳奥氏体相增韧是当前研究的重点之一。亚稳奥氏体可以通过相变过程及与裂纹的相互作用导致裂纹的偏转/钝化,来提高材料断裂韧性,但相变产生的新鲜马氏体具有本征脆性,同时微观结构中复杂的力学配分行为改变了裂纹尖端的应力状态,导致相变增韧效应的减弱甚至材料的脆化。本文综述了亚稳奥氏体对高强钢断裂韧性影响的研究进展,总结了其增韧及脆化机制,并展望了未来面向协同强韧化的亚稳奥氏体设计及理论研究。Incorporating metastable austenite is the one of the key strategies for achieving synergistic improvement in the strength and ductility of high-strength steels.Through in situ deformation-induced martensitic transformation during tensile loading,metastable austenite can delay necking while enhancing work-hardening capacity.Concurrently,ultrahigh-strength steel components are facing increasing demands in terms of lightweightness and service in complex environments;hence,they will be required to have a higher fracture toughness without compromising strength.Research has focused on incorporating the tougher austenite phase in high-strength steels to improve their fracture toughness and preserve ductility.Metastable austenite contributes to enhanced fracture toughness through transformation toughening and its interactions with cracks,which can deflect or blunt cracks.However,freshly formed martensite,a product of martensitic transformation,can reduce the toughening effect or even deteriorate fracture toughness due to its inherent brittleness and effect on the local stress state.This paper reviews recent research progress on the relationship between metastable austenite and fracture toughness of highstrength steels,examining the toughening and embrittlement mechanisms of the phase.In addition,it outlines future design principles for metastable austenite incorporation in high-strength steels to achieve synergistic improvements in strength and toughness.

关 键 词：亚稳奥氏体 断裂韧性 相变 

分 类 号：TG142[一般工业技术—材料科学与工程]