气雾化镍基高温合金粉体的过冷度和显微组织特征（英文）  

Undercooling and Microstructure of Gas Atomized Ni-based Superalloy Powders

作　　者：陈仕奇[1] 逯峙[2] 王广欣[2] Chen Shiqi;Lu Zhi;Wang Guangxin(State Key Laboratory of Powder Metallurgy,Central South University,Changsha 410083,China;Research Center for High Purity Materials, Henan University of Science and Technology,Luoyang 471023,China)

机构地区：[1]中南大学粉末冶金国家重点实验室,湖南长沙410083 [2]河南科技大学高纯材料研究中心,河南洛阳471023

出　　处：《稀有金属材料与工程》2018年第12期3604-3609,共6页Rare Metal Materials and Engineering

基　　金：National Natural Science Foundation of China(U1504516);Educational Commission Foundation of Henan province of China(16A430016)

摘　　要：雾化技术是一种获得微细球形合金粉体的有效方法,其中雾化过程中的过冷度是影响粉体性能的重要因素。借助DSC等实验手段,研究了镍基高温合金粉体尺寸和冷却速度对粉体过冷度和显微组织的影响,以及粉体尺寸,冷却速度和过冷度之间的关系。结果表明,粉体尺寸和冷却速度越小,粉体冷却时的过冷度越大。同时,较大的过冷度会显著降低粉体中树枝晶的臂间距。另外,粉体尺寸越小,粉体中的胞状晶的比例越高,晶粒的尺寸也显著减小。Atomization is an effective approach to obtain fine and spherical alloy powders. Undercooling is an important factor that can affect the property of powders during atomization. The effects of powder size and cooling rate on the undercooling and microstructure of powders were investigated, and the relation between powder size, cooling rate and undercooling was obtained through DSC. The results show that a small powder size and a low cooling rate will result in a large undercooling. Meanwhile, it is found that when the undercooling is large, the dendrite arm spacing of the particles decreases. The smaller the powder size, the greater the proportion of cellular grains, and the finer the grain size of the powders.

关 键 词：雾化 粉体 过冷度 镍基合金 

分 类 号：TF123.71[冶金工程—粉末冶金]