淬火温度对AF9628超高强度钢组织和力学性能的影响

Effect of quenching temperature on microstructure and mechanical properties of AF9628 ultra-high strength steel

通过光学显微镜(OM)、扫描电镜(SEM)、透射电镜(TEM)和X射线衍射等研究了不同温度淬火对AF9628超高强度钢力学性能和微观组织的影响。结果表明:随着淬火温度的升高,AF9628钢的晶粒逐渐长大,未溶相逐渐溶解,抗拉强度和屈服强度呈现逐渐下降趋势,冲击吸收能量、伸长率和断面收缩率先升高后降低。当淬火温度为970℃时,试验钢的晶粒较为均匀,未溶相大部分溶解,仅剩余微量的碳化物,此时钢的塑性较好,同时有足够的强度,其伸长率、断面收缩率、冲击吸收能量、抗拉强度和屈服强度分别为15%、59%、100 J、1746 MPa和1357 MPa。

Effect of quenching at different temperatures on mechanical properties and microstructure of AF9628 ultra-high strength steel was studied by means of optical microscope(OM),scanning electron microscopy(SEM),transmission electron microscopy(TEM)and X-ray diffraction.The results show that with the increase of quenching temperature,the grains of the AF9628 steel gradually grow up,the undissolved phase gradually dissolves,the tensile strength and yield strength show a gradual downward trend,and the impact absorbed energy,elongation and section shrinkage first increase and then decrease.When the quenching temperature is 970℃,the grain of the experimental steel is relatively uniform,most of the undissolved phase is dissolved,and only a small amount of carbide is left.At this time,the steel has good plasticity and sufficient strength,its elongation,section shrinkage,impact absorbed energy,tensile strength and yield strength are 15%,59%,100 J,1746 MPa and 1357 MPa,respectively.