等离子旋转电极雾化FGH95高温合金粉末颗粒凝固组织特征  

MICROSTRUCTURE CHARACTERISTICS OF FGH95 SUPERALLOY POWDERS PREPARED BY PREP

作　　者：陈焕铭[1] 胡本芙[1] 李慧英[1] 余泉茂[1] 张义文[2] 

机构地区：[1]北京科技大学材料科学与工程学院 [2]钢铁研究总院,北京100081

出　　处：《金属学报》2003年第1期30-34,共5页Acta Metallurgica Sinica

基　　金：国家计委"九五"攻关项目95-YJ-20

摘　　要：对等离子旋转电极雾化(PREP)FGH95高温合金粉末颗粒凝固组织特征进行研究,并用数值分析方法计算了FGH95合金粉末凝固过程中冷却速率与粉末粒度之间的关系,结果表明:粉末颗粒表面凝固组织主要是树枝晶和胞状长大晶,随着粉末颗粒尺寸的减小,内部凝固组织由树枝晶为主逐渐转变为以胞状晶及微晶组织为主,冷却速率与粉末粒度之间的关系为T=2.267×109d-1.649,由此得出FGH95合金二次枝晶臂距与冷却速率之间的关系为S=36.2T-0.24.The microstructure characteristics of FGH95 superalloy powders prepared by plasma rotating electrode processing (PREP) have been investigated by using SEM. The relation between cooling rate and particle size of PREP FGH95 alloy powders has been calculated through numerical analysis based on Newtonian heat transfer formulation coupled with the classical heterogeneous nucleation. The results indicate that the solidification microstructures of particle surface are dendrite and cellular structures. With decreasing of the particle size, the microstructures of particle interior change from dendrite in major to cellular and microcrystal structures. The relation between droplet cooling rate and particle size can be expressed by T = 2.267 x 10(9)d(-1.649) during solidification. Thus, the relation of secondary arm space and cooling rate of FGH95 superalloy is concluded as S = 36.2T(-0.24).

关 键 词：等离子旋转电极 雾化 FGH95高温合金粉末 凝固组织 

分 类 号：TF125.212[冶金工程—粉末冶金] TG146.15[冶金工程—冶金物理化学]