摘要
在 760-1050℃和780-115 MPa范围内,选择不同温度和应力配合进行了持久拉伸实验,研究了温度和应力的变化对试件断裂寿命的影响以及温度、应力和断裂寿命与共格相特征尺寸(基体相γ水平通道宽度、筏形析出相γ厚度)和试件延伸率及断面收缩率的关系.结果表明,在各实验条件下,γ除了进行定向粗化以外,相邻数列γ还可沿外应力轴方向发生不同程度的纵向合并,尽管在较高的温度下外应力较低。
Sustaining tensile tests were carried out by combining elevated temperatures with declined stresses over the range of 760-1050℃ and 780-115 MPa. The effects of temperature and applied stress on rupture life, and the relations of temperature, applied stress and rupture life to characteristic dimensions of coherent phases (γ matrix channel width and rafted γ precipitate thickness), and to the elongation as well as to the cross sectional area reduction of the tested specimens were investigated. Under all testing conditions, longitudinal coalescence of several adjacent arrays of γ precipitates could occur to different extents along the direction of the applied stress axis in addition to their normal directional coarsening. The extent of longitudinal coalescence became increased and the morphology tended to be irregular with the increase of temperature although the applied stresses were relatively lower. The experimental results are analyzed and discussed in the paper.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
1999年第3期265-270,共6页
Acta Metallurgica Sinica
基金
湖北省自然科学资助项目!95J63
关键词
镍基
高温合金
持久拉伸
显微组织形态
力学行为
single crystal Ni-base superalloy, sustaining tension, characteristic phase dimension, longitudinal coalescence, rupture life