Effect of cooling rate on MC carbide in directionally solidified nickel-based superalloy under high

• 作 者: Zhang Weiguo Liu Lin Fu Hengzhi
• 机 构: College of Mechanical & Electronic Engineering, Northwest A & F University, Yangling 712100, China;S
• 出 处: 中国铸造
• 发表日期: 2012年1期
• 关键词: directional solidification cooling rate nickel-based superalloy MC carbide

A series of directional solidification experiments have been performed to study the effect of cooling rate on the precipitation behavior of MC carbide in nickel-based superalloy under the temperature gradient of 500 K.s-1.Results reveal that the morphology of MC carbide changes from coarse block to fine strip,then to Chinese-script,and their sizes reduce gradually with the increasing of cooling rate from 2.53 K·s-1 to 36.4 K·S-1.At low cooling rates,most of these carbides are found to be located at the grain boundary and interdendritic regions,while the coupled growth of some carbides and γ matrix in the center of γ grains is occurred at high cooling rate.The main elements forming MC carbide are Ta,W,and Hf.