(北京航空材料研究院, 北京 100095)
摘 要: 评述了超高强度钢和高强度不锈钢的基本理论、 成分设计、 超纯净熔炼和工程应用技术发展状况、 在航空、 航天及其他高科技领域中的应用和重要地位、发展目标、 强韧化机理和成分探索研究现状及存在问题。 借助透射电子显微镜高分辨和电子选区衍射等方法， 揭示了超细马氏体板条、 超细共格沉淀强化相Laves相、 M2C及逆转变奥氏体等强-韧化机理。 用VIM+VAR双真空超纯洁熔炼、超均匀加工及控制相变热处理等技术， 获得2种低碳超高强度高韧性不锈钢，其力学性能分别达到抗拉强度1915MPa和1862MPa, 断裂韧度119MPa·m1/2和120MPa·m1/2。
关键字: 超高强度钢； 不锈钢； 强-韧化机理
（Beijing Institute of Aeronautical Materials, Beijing 100095, China）
Abstract:The fundamental theory, future object, studying status and topics of ultra-high strength steel and high strength stainless steel were reviewed. The new strengthen-toughening mechanisms, such as ultrafine martensitic laths, ultrafine strengthening phases M2C carbide and Laves phase precipitated coherence with martensitic matix and reverse transformed austenite distributed over the effective grain boundaries were discovered with electronic microscopy. By means of VIM+VAR double vacuum melting technology secured super pure materials and by the super homogenization hotwork and controlling martensitic transformation heat treatment techniques, the new types of low carbon ultra-high strength steel in combination with high toughness were obtained. The tensile strengths reach 1915MPa and 1862MPa and the fracture toughnesses reach 119MPa and 120MPa·m1/2 respectively.
Key words: ultra-high strength steel; stainless steel; strengthen-toughening mechanism
