H13改进型热作模具钢的组织与性能

 研究了高锰型马氏体热作模具钢SDH3-Mod的室温冲击韧性、回火稳定性和热疲劳性能，并结合透射电镜(TEM)分析了锰对其微观组织的影响。结果表明：SDH3-Mod钢回火组织中残余奥氏体以薄膜状存在于马氏体板条间，提高冲击韧性，延缓裂纹扩展；同时，锰在高温时阻碍碳化物粗化长大和延迟基体的回复再结晶，提高抗回火软化能力和热疲劳性能，使SDH3-Mod性能优于H13。

Microstructure and Mechanical Properties of Modified-H13 Hot Working Die Steel

The mechanical and thermal fatigue properties of high manganese SDH3-Mod hot working die steel were investigated and influence of manganese on the microstructure were also studied by transmission electron microscopy (TEM). The results reveal that the retained austenite exists as thin film between the lath martensite which improves toughness and slows fatigue cracks propagation. Meanwhile, the coarsening of carbides is efficiently inhibited and softening of steels is sufficiently delayed which improves the resistance of tempering and thermal fatigue because of the addition of manganese. Consequently, SDH3-Mod shows a more significant improvement on the mechanical properties than H13.