【摘要】 以9%Ni钢为材料研究了镍钢中"逆转变奥氏体"的形成问题。实验表明;"逆转变奥氏体"(γ′)于540℃开始形成,渗碳体(θ)在540℃以前析出。θ及γ′相与基体(α)之间分别存在Bagaryatskii和Kurdjmov-Sachs取向关系。延长回火时间,γ′相粒子数量增多并长大。提出了γ′相形成的可能机制。讨论了γ′相在较低的回火温度下形成的原因,认为是由于回火过程中合金元素镍在局部地区偏聚引起的。更多还原

【Abstract】 The formation"reverse austenite"in 9% Ni steel was studied as a typical in nickel steel.Experimental results showed that the formation of"reverse austenite" (γ′)begins at 540℃ and cementite(θ)is precipitated from martensite earlier below 540℃.The orientation between θ,γ′ phase and the matrix martensite obey the Bagaryatskii and Kurdjmov-Sachs relationship.The number and size of γ′ particles are increasing with the increase of tempering time.The possible mechanism of γ′ formation has been suggested.It isfurther indicated that theformation of γ′ is the result of segregation of nickel during the tempering of martensite, thereby in certain locations the nickel content is increased,so that the beginning of formation of γ′ at a lower tempering temperature.更多还原