摘要
研究了不同抽拉速度下镍基高温合金DZ125定向凝固试样中显微缩松的分布、变化规律。结果表明,在一定抽拉速度范围内(v≤100μm/s),随抽拉速度增加,定向凝固试样中缩松水平降低。v=50μm/s时试样中缩松水平约为v=5μm/s时缩松水平的10%,v=100μm/s时试样中的缩松水平约为v=50μm/s时缩松水平的70%～90%。随抽拉速度增大,一次枝晶间距和二次枝晶间距减小,枝晶发生细化,抽拉速度对缩松水平的影响主要由枝晶间距的变化引起。
Directional solidification experiments were carried out on nickel based super-alloy DZ125 under withdrawal rates of 50μm/s, 50μm/s and 100μm/s in order to investigate the distribution and variation of the micro-porosity. The results show that with the increasing of withdrawal rate the micro-porosity level of the samples decreases. The micro-porosity level at v=50μm/s is about 10 percent of that at v=5μm/s and the micro-porosity level at v=100 μm/s is about 70-90 percent of that at v=50μm/s. The primary arm spacing and the secondary arm spacing both decrease while the withdrawal rate increases. The influence of withdrawal rate on the micro-porosity level depends on the arm spacing.
出处
《铸造》
CAS
CSCD
北大核心
2009年第5期427-430,共4页
Foundry
关键词
镍基高温合金
定向凝固
抽拉速度
显微缩松
nickel based super-alloy
directional solidification
withdrawal rate
micro-porosity
