摘要
研究了NASAIR100单晶在高温持久变形中γ′筏形组织的形成及其在缩颈区内的转动,发现γ′沉淀在持久变形初期即沿着垂直于拉伸应力轴的方向相互连结,变形大约50h后形成了完善的γ′筏形组织,对拉断试样的纵截面进行了扫描电镜观察,发现缩颈区内的γ′筏形组织不再垂直于应力轴,而是绕着应力轴转动,初步提出了γ′筏形组织的形成及转动机理。
The formation of γ' rafts and their rotation in the necking zone during high temperature stress-rupture tests of NASA IR100 single crystal superalloy were investigated.It was found that γ' precipitates linked each other in the direction of perpendicular to the stress axis just after the beginning of the stress-rupture test. Perfect and regularγ' rafts formed when the stress-rupture test lasted for about 50 h. After observing the longitudinal sections of ruptured bars by SEM the γ' rafts in the necking zones were found to be not perpendicular to the stress axis, but rotated around the stress axis. The mechanisms of γ' raft formation and rotation were put forward in this paper.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
1994年第7期A321-A326,共6页
Acta Metallurgica Sinica
基金
国家自然科学基金
关键词
单晶高温合金
久变形
γ'筏形组织
single crystal superalloy, high temperature stress-rupture deformation,γ' raft, NASA IR100