文献类型：期刊文献

英文题名：Failure analysis of the final stage blade in steam turbine

作者：Wang, Wei-Ze[1]; Xuan, Fu-Zhen[1]; Zhu, Kui-Long[1]; Tu, Shan-Tung[1]

机构：[1]E China Univ Sci & Technol, Sch Mech & Power Engn, Shanghai 200237, Peoples R China

年份：2007

卷号：14

期号：4

起止页码：632

外文期刊名：ENGINEERING FAILURE ANALYSIS

收录：;EI(收录号：20070410383284);WOS:【SCI-EXPANDED(收录号:WOS:000244234400012)】；

语种：英文

外文关键词：turbine blade; failure analysis; fractography; fatigue; mechanical properties

摘要：A failure case of the low pressure blades of steam turbine is presented in this paper. The suction side of blades has been quenched to improve the erosion resistance. Cracks with different lengths were found in the quenched region of final stage blades after about 13,200 h service. The failure analysis of blades was performed in terms of composition analysis, microstructure and mechanical tests, etc. The yield strength and tensile strength conform to the corresponding standard, whereas the elongation, area reduction and impact toughness are lower than the criteria. From the crack morphology, fractography and composition analysis on the fracture surface, it was found that the failure mechanism of blades is the environment-assisted fatigue fracture. The location of fatigue crack initiation is related with the salient of blades due to the stress concentration. In order to decrease the blade cracking susceptibility, the increment of tempered temperature in both modified treatment and high-frequency hardening was recommended. (c) 2006 Elsevier Ltd. All rights reserved.