INFLUENCE OF RESIDUAL STRESS IN MEASUREMENT OF APPARENT FRACTURE TOUGHNESS
The measurement of fracture toughness, K1C, in laboratory specimens is commonly made under the assumption that there is no influence of residual stresses on the measured values. In other words, it is assumed that the extraction of test specimens from the sample of interest totally relaxes any residual stresses present. Due to the large degree of scatter commonly observed in experimental fracture testing, particularly when the principal failure mechanism is cleavage fracture, it is often difficult to distinguish between an erroneous value caused by the retention of residual stress in the test specimen and one near the limits of the statistical distribution characterising the expected scatter. By means of a simple statistical study considering the representative case of cleavage fracture in A533B ferritic steel, this paper aims to quantify the levels of residual stress needed to produce a statistically significant shift in toughness. In the example considered, it was found that a relatively high magnitude of residual stress, approximately one third of the room temperature yield stress, was required to cause a statistically measurable shift in apparent fracture toughness.
S. J. Lewis D. J. Smith J. D. Booker C. E. Truman
Department of Mechanical Engineering, University of Bristol, Queen’s Building, University Walk, Bristol, BS8 1TR, UK
国际会议
第九届工程结构完整性国际会议(The Ninth International Conference on Engineering Structural Integrity Assessment)
北京
英文
2007-10-15（万方平台首次上网日期，不代表论文的发表时间）