时效对10Ni10Mn2CuAl钢组织及性能的影响

基于富Cu相和NiAl(Mn)相复合沉淀析出强化的方式设计了一种新型高强度舰船用钢10Ni10Mn2CuAl，探究了时效处理工艺对10Ni10Mn2CuAl钢的组织及性能的影响.采用Thermo-Calc软件对析出相析出温度和含量进行理论计算，采用光学显微镜、扫描电子显微镜(SEM)对基体典型夹杂及对时效处理后组织进行了分析，并进行了性能测试.研究结果表明:钢中富Cu相析出温度区间为300~606℃，最高质量分数为1.41%.随时效时间增加，马氏体板条呈现粗化到细化演变，硬度增加到峰值后趋于稳定.随时效温度升高加速析出相析出过程，硬度达到峰值的时间缩短.在最佳热处理工艺下(500℃时效24h)，实验钢屈服强度为1435.51MPa，抗拉强度为1555.42MPa，延伸率为8%，综合性能达到最优.

Effect of Aging Treatment on Microstructure and Mechanical Properties of 10Ni10Mn2CuAl Steel

A new type of high-strength marine steel with the composition of 10Ni10Mn2CuAl was designed by means of precipitation strengthening from hybrid Cu-rich and NiAl (Mn) phases， and the effect of aging treatment on microstructure and mechanical properties of the 10Ni10Mn2CuAl steel was studied. The precipitating temperature and the phase content of the precipitations were calculated by Thermo-Calc software. The typical inclusions in the matrix and microstructure after aging treatment were analyzed by optical，scanning electron microscopes，the hardness and room-temperature tensile tests were carried out. The results show that the precipitating temperature of Cu-rich phase is in the range of 300~606℃ and the maximum content of the precipitation is 1.41%. With the aging time increasing， the martensitic lath changes from the coarse grain to the refined one， corresponding to the hardness reaching the maximum and then becoming stable. Meanwhile， as the aging temperature increases， the time to reach the maximum hardness is shortened owing to the precipitation process accelerated by higher temperature. Under the heat treatment of the aging at 500℃ for 24 h， the best performance of the experimental steel is achieved with yield strength of 1435.51MPa， tensile strength of 1555.42MPa and elongation of 8%.