热处理对Fe-Cr-Ni低碳马氏体不锈钢组织及性能的影响

通过真空电弧熔炼方法制备了Fe-13Cr-3.5Ni不锈钢,并系统研究了不同热处理工艺对其微观组织以及硬度的影响。结果表明:熔炼态Fe-13Cr-3.5Ni不锈钢为典型的板条状马氏体组织;经过不同温度固溶和回火处理(600 ℃)后,其组织结构由板条状马氏体和少量残留奥氏体组成,残留奥氏体含量随着固溶温度的升高先增加后减少,而硬度值先降低后升高,硬度最低值为101.5 HRB;在1000 ℃淬火并在不同温度回火后其组织结构由回火板条状马氏体以及残留奥氏体组成,在650 ℃以下回火时,随着回火温度的升高奥氏体含量逐渐增多,当回火温度达700 ℃时,残留奥氏体含量下降,其洛氏硬度值随着回火温度的升高先降低后升高,其硬度值在99~107 HRB范围内。

Effect of heat treatment on microstructure and properties of Fe-Cr-Ni low carbon martensitic stainless steel

Fe-13Cr-3.5Ni stainless steel was prepared by vacuum arc melting method, and the effects of different heat treatment processes on its microstructure and hardness were systematically studied. The results show that the Fe-13Cr-3.5Ni stainless steel in smelting-casting state is of typical lath martensite structure. After solid solution treatment at different temperatures and tempered at 600 ℃, the steel consists of lath martensite and a small amount of retained austenite. The content of retained austenite increases firstly and then decreases with the increase of solution treatment temperature, but the hardness firstly decreases and then increases, with the minimum hardness being 101.5 HRB. After quenched at 1000 ℃ and tempered at different temperatures, the steel microstructure is composed of tempered lath martensite and retained austenite. When tempered below 650 ℃, the austenite content gradually increases with the increase of tempering temperature. When the tempering temperature reaches 700 ℃, the retained austenite content decreases, and the Rockwell hardness decreases first and then increases with the increase of tempering temperature, and is in the range of 99-107 HRB.