刘剑虹
,
何世禹
,
姚枚
金属学报
在TS-2型台式扫描电子显微镜中,装入自制的微型热疲劳试验装置,观察了3Cr2W8V钢热疲劳裂纹长大过程,结果表明:热疲劳裂纹长大前,主裂纹尖端首先钝化,在其前方出现孔洞或不连续微裂纹,热疲劳裂纹的长大通过主裂纹与孔洞及微裂之间的桥接方式进行。
关键词:
3Cr2W8V钢
,
thermal fatigue
,
crack growth
,
in situ observation
T.L. Wang 1
,
2)
,
J.T. Guo 1)
,
D.S. Xia 2)
,
Y.Wang 1) and H.C. Yang 2) 1) Institute of Metal Research
,
Chinese Academy of Science
,
Shenyang 110015
,
China 2) Material and Metallurgical Institute Northeastern University
,
Shenyang 110006
,
China
金属学报(英文版)
Effect of revert cycles on microstructure and fatigue properties of cast cobalt base superalloy K640S has been investigated. The results show that: at 70 times of cool heat cycles, there were microcracks found in seven times revert and ten times revert. With the increasing of thermal fatigue cycles, the crack of revert grows a little faster than virgin. When the cycle time reaches 200, the crack length for both virgin and reverts have been as long as 2mm. The low cycle fatigue life has no remarkable change, with the increase of revert cycles at 815℃, 360MPa ,0 5Hz. With the times of cycles increasing, it is found that the content of impurity and gas in alloy change a little, and there is no obvious change for dendrite microstructure.
关键词:
revert
,
null
,
null
,
null
,
null
Author M. Miyahara1) and K. Tokimasa2) 1) Corporate Research & Development Laboratories
,
Sumitomo Metal Industries
,
Ltd.
,
Amagasaki
,
Japan2) Department of Mechanical Engineering
,
School of BiologyOriented Science and Technology
,
Kinki University
,
Uchitacho
,
Wakayama
,
JapanManuscript received 18 October 1998
金属学报(英文版)
The authors recent works on the improvement of the Strain Range Partitioning(SRP) method and its application to the life prediction of high temperature structural components are summarized. Examined components are divided into three groups, that is, components in the steel production plants, in the automobile and in the fossil power plants. Based on the results of the inelastic analysis and the creepfatigue properties of the material, which were obtained by IJ(=PP,PC, CP, CC) tests, the effects of the material properties, operating conditions and configuration of components were quantitatively evaluated to select the most effective measures for the thermal fatigue life extension. The SRP has been successfully applied until now to the life prediction and extension of the actual structural components subjected to thermal cycling by the authors.
关键词:
creepfatigue
,
null
,
null
,
null
