摘要
在高温度梯度真空定向凝固炉中,采用螺旋选晶法制备了单晶高温合金,再在1180℃/150 MPa条件下对其进行热等静压,然后进行标准热处理,研究了热等静压对单晶高温合金组织和不同条件下持久性能的影响。结果表明,合金热等静压后,铸态组织的共晶含量基本保持不变,γ′相尺寸增加,立方化程度增加,γ基体通道变宽。热处理组织的γ′相尺寸稍有减小,立方化程度增加。在760℃/800 MPa和980℃/250 MPa条件下,合金的持久寿命增加;而在1100℃/140 MPa条件下,粒状碳化物的析出导致持久寿命没有提高,与未热等静压的合金持平。
A single crystal superalloy with [001] orientation was cast in a directionally solidified furnace. The hot isostatic pressing（HIP） was applied at the condition of 1180 °C/150 MPa. The standard heat treatment was carried out after HIP. The effect of HIP on the microstructure and stress rupture properties at three different conditions has been investigated. The results show that the volume fraction of γ/γ′ eutectic basically holds constant, the size and the cubic extent of γ′ phase increase, while the γ matrix channel broaden in the as-cast microstructure after HIP. In the heat treatment microstructure, the size of γ′ phase decreases and the cubic shape turns regular after HIP. The stress rupture lives of the alloy at 760 °C /800 MP and 980 °C /250 MPa all increase, while the stress rupture life at 1100 °C /140 MPa does not increase because of the granulous carbide precipitating in the stress rupture process.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2015年第9期2300-2304,共5页
Rare Metal Materials and Engineering
关键词
单晶高温合金
热等静压
组织
持久性能
single crystal superalloy
hot isostatic pressing
microstructure
stress rupture properties
作者简介
史振学，男，1975年生，博士，高级工程师，北京航空材料研究院先进高温结构材料重点实验室，北京100095，电话：010-62496338，E-mail：shizhenxue@126．com
