高速钢M42喷射成形余粉组织性能分析

MICROSTRUCTURE AND PROPERTIES ANALYSIS OF SPRAY FORMED M42 HIGH-SPEED STEEL OVERSPRAY POWDER

喷射成形工艺不可避免会产生喷射余粉,对喷射成形高速钢M42喷射余粉进行了成分、气体含量、形貌以及组织性能研究。结果表明,M42喷射余粉氧含量为267×10^(-6)、氮含量为374×10^(-6),大部分粉末呈球形,尺寸为140μm;喷射余粉为树枝晶组织,内部组织为基体+网状碳化物,碳化物类型大部分为M2C类型碳化物,尺寸为0.4~0.6μm,存在少量的M6C类型碳化物,尺寸为2μm。M42喷射余粉粒度呈正态分布,具有较好的流动性且松装密度、振实密度较高,分别达到了理论密度的62%和68%,粉末在后续热等静压包套制备过程中具备良好填充性和均匀性。

The spray forming process inevitably produces residual powder.The composition,gas content,morphology,microstructure and properties of the M42 overspray powder were studied.The results show that the oxygen content and nitrogen content of M42 overspray powder are 267×10^(-6)and 374×10^(-6)respectively,and most of the powder is spherical;The overspray powder with a size of 140μm is a dendritic structure,and the microstructure is a matrix+network of carbides.Most of the carbides are M2C type carbides with size of 0.4~0.6μm.There is a small amount of M6C type carbides with size of 2μm.The particle size of M42 spray residue is normally distributed with good liquidity and high apparent density and tap density.The latter can reach 62%and 68%of the theoretical density.The overspray powder has good filling properties and uniformity in the subsequent hot isostatic pressing canning preparation process.