首页 | 本学科首页   官方微博 | 高级检索  
     


Estimation of high‐temperature fracture parameters for small punch specimen with a surface crack
Authors:Kee Bong Yoon  Thanh Tuan Nguyen
Affiliation:Department of Mechanical Engineering, Chung Ang University, Seoul, South Korea
Abstract:An outline of a newly proposed methodology for evaluating creep crack growth (CCG) parameters using cracked small‐punch (SP) specimens is explained. Three‐dimensional finite element analyses were performed to calculate the stress intensity factor along the crack front for a surface crack formed at the centre of a SP specimen. Effects of crack ratio, (a/t); crack aspect ratio, (a/c); and thickness of the specimen, (t), on the fracture parameters were studied. It was observed that the minimum variation of K‐value along the crack front can be achieved when a/c was 0.50 except the location very near the intersection of the crack and free surface. This condition is similar to the case of constant K‐values along the crack front of the conventional compact tension specimen. Thus, it can be argued that the SP specimen with a surface crack is a suitable specimen geometry for CCG testing. The proposed CCG test method was found to be practically applicable for the crack geometry of 0.10 to 0.30 of a/t with constant aspect ratio of 0.50. An estimation of the K and Ct‐parameter under the small scale creep condition was derived. Future work for further development of the suggested CCG testing is discussed.
Keywords:Ct‐parameter  creep crack growth  small‐punch creep test  stress intensity factor  surface crack
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号