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对喷射成形H13热锻模沉积坯进行了金相分析、SEM组织形貌观察和能谱分析、硬度宏观分布测试。结果表明:喷射沉积H13钢的凝固晶粒为细小等轴晶,晶粒大小分布不均匀;喷射态的微观组织主要由贝氏体、马氏体、残留奥氏体组成,并有少量碳化物及夹杂物;喷射沉积坯的宏观组织存在明显层状特征,层与层之间存在不同程度的孔隙,沉积坯的底部及顶部区域的孔隙率高;孔隙率高、组织不均匀是沉积坯硬度分布不均的原因;造成沉积坯组织不均匀的原因是金属液流温度和速度在整个喷射过程不均匀。
The spray forming H13 hot forging die deposition billet metallographic analysis, SEM morphology and energy spectrum analysis, the hardness of the macro distribution test. The results show that the solidified grains of spray-deposited H13 steel are fine equiaxed grains and the grain size distribution is not uniform. The microstructure of sprayed state mainly consists of bainite, martensite and retained austenite, with a small amount of carbides And inclusions. The macro-structure of the sprayed blank has obvious layered features with different porosity between the layers and the bottom and top of the blank have high porosity. The porosity is high and the microstructure is uneven The reason of the uneven distribution of the microstructure is that the temperature and velocity of the metal flow are not uniform throughout the spraying process.