氩气雾化制备新型镍基高温合金粉末的微观结构和性能

Microstructure and properties of new nickel-based superalloy powder prepared by argon atomization

采用氩气雾化制备Al、Ti总质量分数小于4%的选区激光熔融用新型镍基高温合金粉末,对粉末的成分、物相组成、形貌、微观结构和性能等进行分析和表征。结果表明,新型镍基高温合金粉末的Al、Ti总质量分数为3.82%。小粒径粉末(粒径<20μm)内部结构致密,以胞状晶组织为主,成分均匀,显微硬度(HV)达到265。随粉末粒径增大,粉末内部树枝晶数量增多,少量大粒径(粒径>40μm)粉末内部出现凝固缩孔和颗粒包覆缺陷。筛分后得到的粒径为15~44μm的粉末,粒径分布集中,中位径DV50为19.7μm,流动性和松装密度分别达到15.14 s/50 g和4.15 g/cm^(3)。

New nickel-based superalloy powder for selective laser melting with a total mass fraction of Al and Ti less than 4%was prepared by argon atomization.The composition,phase,morphology,microstructure and properties of the new nickel-based superalloy powder were characterized.The results show that the total mass fraction of Al and Ti in the new nickel-based superalloy powder was 3.82%.Small particle size powder(particle size<20μm)has a compact interior structure,mainly cellular structure,and uniformly composition,and its micro-hardness(HV)reaches 265.As the particle size of the powder increases,the number of dendrites in the powder increases,and solidification shrinkage pore and particle-coating defect appear in some large-diameter(particle size>40μm)powder.After sieving,the powder with a particle size of 15−44μm has a concentrated particle size distribution,a median diameter D_(V50) of 19.7μm,the flow-ability and apparent density are 15.14 s/50 g and 4.15 g/cm^(3),respectively.