中文摘要：

采用扫描电镜（SEM）、能谱仪（EDS）、光学显微镜结合硬度仪和Jmatpro软件对比研究了氮含量对4Cr5Mo2V压铸模具钢热稳定性能的影响。结果表明：同等淬回火硬度条件下,3种氮含量的4Cr5Mo2V钢在600℃和650℃保温时分别表现出不同的软化行为,且随着氮含量的增加,硬度下降更快,碳化物粗化更明显,热稳定性能越差。因此,减少氮含量有利于提高4Cr5Mo2V压铸模具钢的热稳定性能,大大延长压铸模具使用寿命。

英文摘要：

The effect of nitrogen content on thermal stability property of 4Cr5Mo2V die-casting die steel was studied by using scanning electron microscope （SEM）, energy spectrometer （EDS）, hardness tester and Jmatpro software. The resuhs show that when the quenched and tempered hardness is close, the three tested 4Cr5Mo2V steels show different softening behavior holding at 600℃ and 650℃, respectively. Meanwhile, the hardness decreases faster because of the carbides coarsening more serious with increasing nitrogen content, resulting in poor thermal stability property. Therefore, reducing nitrogen content is beneficial to improve thermal stability property of 4Cr5Mo2V die-casting die steel and greatly extend the lifetime of die-casting dies.