Case studies in engineering failure analysis最新文献

筛选
英文 中文
Cantilever steel post damaged by wind 悬臂钢柱被风损坏
Case studies in engineering failure analysis Pub Date : 2014-10-01 DOI: 10.1016/j.csefa.2014.09.001
Wei Sha , Savko Malinov
{"title":"Cantilever steel post damaged by wind","authors":"Wei Sha ,&nbsp;Savko Malinov","doi":"10.1016/j.csefa.2014.09.001","DOIUrl":"10.1016/j.csefa.2014.09.001","url":null,"abstract":"<div><p>An analysis for the cause of fracture failure of a cantilever steel sign post damaged by wind has been carried out. An unusual cause of failure has been identified, which is the subject of this paper. Microscopy and microanalysis of the fracture surface showed that the failure was due to pre-existing cracks, from the fabrication of the post. This conclusion was reached after detecting and analysing a galvanised layer on the fracture surfaces.</p></div>","PeriodicalId":91224,"journal":{"name":"Case studies in engineering failure analysis","volume":"2 2","pages":"Pages 162-168"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.csefa.2014.09.001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"54176767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
In vivo shell-like fractures of veneered-ZrO2 fixed dental prostheses 贴面zro2固定义齿体内壳状骨折的研究
Case studies in engineering failure analysis Pub Date : 2014-10-01 DOI: 10.1016/j.csefa.2014.06.001
Renan Belli , Susanne S. Scherrer , Sven Reich , Anselm Petschelt , Ulrich Lohbauer
{"title":"In vivo shell-like fractures of veneered-ZrO2 fixed dental prostheses","authors":"Renan Belli ,&nbsp;Susanne S. Scherrer ,&nbsp;Sven Reich ,&nbsp;Anselm Petschelt ,&nbsp;Ulrich Lohbauer","doi":"10.1016/j.csefa.2014.06.001","DOIUrl":"10.1016/j.csefa.2014.06.001","url":null,"abstract":"<div><p>Fractographic analyses are performed in two fixed dental prosthetic reconstructions made of ZrO<sub>2</sub> frameworks covered by a veneering ceramic that fractured during function in the mouth. Processing histories, material properties, recovered broken parts and replicas of the fracture surface were used, along with fractographic markings to determine fracture origins and cause of failure. A shell-like fracture pattern was found common for both cases, although different factors were identified to be involved in each fracture event. Internal thermal residual stresses and occlusal surface defects from localized contact overloading were found to precipitate the fracture in Case 1, whereas extreme occlusal surface damage from sliding chewing contact was determinant in the fracture of Case 2. The interface between the veneering ceramic and the ZrO<sub>2</sub> framework was unaffected by the fractures.</p></div>","PeriodicalId":91224,"journal":{"name":"Case studies in engineering failure analysis","volume":"2 2","pages":"Pages 91-99"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.csefa.2014.06.001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"54176666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 17
Failure analysis of re-bars during bending operations 钢筋弯曲失效分析
Case studies in engineering failure analysis Pub Date : 2014-10-01 DOI: 10.1016/j.csefa.2014.04.003
Souvik Das, Jitendra Mathur, Tanmay Bhattacharyya, Sandip Bhattacharyya
{"title":"Failure analysis of re-bars during bending operations","authors":"Souvik Das,&nbsp;Jitendra Mathur,&nbsp;Tanmay Bhattacharyya,&nbsp;Sandip Bhattacharyya","doi":"10.1016/j.csefa.2014.04.003","DOIUrl":"10.1016/j.csefa.2014.04.003","url":null,"abstract":"<div><p>Thermo-mechanical treated (TMT) rebar is suitable material for reinforcing concrete structures on accounts of similarity in thermal expansion, ability to bond well with concrete and, above all the ability to shoulder most of the tensile stress acting on the structure and also steel manufacturing industry has successfully developed a corrosion-resistant variety of rebar for the construction industry. As the TMT is the finish product thus proper control of rolling parameters and water box is needed to achieve adequate property. Water box plays an important role for achieving the final structure and property of the rebars. Water box is responsible for outer rim formation and which helps to achieve the yield strength of the material. The present paper highlights failure investigation of a failed rebar during bending operations. From fractography and microstructural analysis it is confirmed that the rebar sample failed in brittle manner due to through harden martensitic structure and which indicates that there is some anomaly in water box resulting in these premature failures.</p></div>","PeriodicalId":91224,"journal":{"name":"Case studies in engineering failure analysis","volume":"2 2","pages":"Pages 51-53"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.csefa.2014.04.003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"54176603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 9
Crack of a first stage blade in a steam turbine 汽轮机第一级叶片的裂纹
Case studies in engineering failure analysis Pub Date : 2014-10-01 DOI: 10.1016/j.csefa.2014.04.002
M. Nurbanasari , Abdurrachim
{"title":"Crack of a first stage blade in a steam turbine","authors":"M. Nurbanasari ,&nbsp;Abdurrachim","doi":"10.1016/j.csefa.2014.04.002","DOIUrl":"10.1016/j.csefa.2014.04.002","url":null,"abstract":"<div><p>The failure of the first stage blade in a steam turbine of 55<!--> <!-->MW was investigated. The blade was made of 17-4 PH stainless steel and has been used for 12 years before failure. The current work aims to find out the main cause of the first stage blade failure. The methods for investigation were metallurgical analysis, chemical composition test, and hardness measurement. The result showed that there was no evidence the blade failure was due to material. The damage found on the blade namely crack on the blade root. Two locations of the crack observed at the blade root, which was at the tang and the fillet, with different failure modes. In general, the damage of the blade was started by the corrosion occurred on the blade root. The crack at the blade root tang was due to corrosion fatigue and the crack occurred at the blade root fillet owing to stress corrosion cracking.</p></div>","PeriodicalId":91224,"journal":{"name":"Case studies in engineering failure analysis","volume":"2 2","pages":"Pages 54-60"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.csefa.2014.04.002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"54176596","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 29
Failure analysis of cracked brass turrets used in electronic circuits 电子电路用破裂黄铜塔的失效分析
Case studies in engineering failure analysis Pub Date : 2014-10-01 DOI: 10.1016/j.csefa.2014.04.004
Nirmal Ninan, S.V.S. Narayana Murty, Sushant Manwatkar, P. Ramesh Narayanan
{"title":"Failure analysis of cracked brass turrets used in electronic circuits","authors":"Nirmal Ninan,&nbsp;S.V.S. Narayana Murty,&nbsp;Sushant Manwatkar,&nbsp;P. Ramesh Narayanan","doi":"10.1016/j.csefa.2014.04.004","DOIUrl":"10.1016/j.csefa.2014.04.004","url":null,"abstract":"<div><p>Copper alloys are widely used in electrical circuits mainly due to their electrical conductivity. In electrical circuits, solder terminals are used to provide multiple electrical connections and swage type turret terminals are preferred owing to their high reliability under dynamic environments where the electrical systems are subjected to higher vibrations and line currents, as in the case of satellite launch vehicles. Owing to high machinability, free-cutting brass is preferred in the manufacture of such small sized terminals, which will be cold worked/swaged to the printed circuit boards. Improper selection of the composition of free-cutting brass can lead to cracking of the terminals, thereby affecting the reliability of the system. This paper describes cracking of turret terminals made of free cutting brass during swaging operation. The crack propagation tendency during cold working of brass turret terminals made from different compositions is studied through optical and scanning electron microscopy. Finally, composition for obtaining crack free terminals during swaging is suggested for applications involving cold swaging.</p></div>","PeriodicalId":91224,"journal":{"name":"Case studies in engineering failure analysis","volume":"2 2","pages":"Pages 107-117"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.csefa.2014.04.004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"54176611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 7
Failure analysis of a bearing in a helicopter turbine engine due to electrical discharge damage 直升机涡轮发动机某轴承放电损伤失效分析
Case studies in engineering failure analysis Pub Date : 2014-10-01 DOI: 10.1016/j.csefa.2014.05.003
Michael K. Budinski
{"title":"Failure analysis of a bearing in a helicopter turbine engine due to electrical discharge damage","authors":"Michael K. Budinski","doi":"10.1016/j.csefa.2014.05.003","DOIUrl":"10.1016/j.csefa.2014.05.003","url":null,"abstract":"<div><p>This article documents the metallurgical evaluation of a rolling element bearing that failed due to electrical discharge damage. This rolling element bearing was used in a helicopter turbine engine that failed in-flight, resulting in a hard landing of the helicopter. Optical and electron microscopy as well as energy dispersive spectroscopy were used to evaluate the bearing. Pitting and material transfer on the external bearing races bearing and mating surfaces revealed that the electrical discharge damage occurred while the engine's components were not rotating.</p></div>","PeriodicalId":91224,"journal":{"name":"Case studies in engineering failure analysis","volume":"2 2","pages":"Pages 127-137"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.csefa.2014.05.003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"54176650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 8
Failure analysis of a helical compression spring for a heavy vehicle's suspension system 重型车辆悬架系统螺旋压缩弹簧失效分析
Case studies in engineering failure analysis Pub Date : 2014-10-01 DOI: 10.1016/j.csefa.2014.08.001
Youli Zhu, Yanli Wang, Yuanlin Huang
{"title":"Failure analysis of a helical compression spring for a heavy vehicle's suspension system","authors":"Youli Zhu,&nbsp;Yanli Wang,&nbsp;Yuanlin Huang","doi":"10.1016/j.csefa.2014.08.001","DOIUrl":"10.1016/j.csefa.2014.08.001","url":null,"abstract":"<div><p>This paper analyzed why a compression coil spring fractured at the transition position from the bearing coil to the first active coil in service, while the nominal stress here should always be much less than that at the inside coil position of a fully active coil. Visual observations indicated that a wear scar was formed on the first active coil and the fracture surface showed radiating ridges emanating from the wear scar. Scanning electron microscopy examination showed crescent shaped region and beach marks, typical of fatigue failure. ZnCaph phosphate layer and painting around the contact zone were worn out due to contact and friction and resulted in corrosion and corrosion pits induced local stress concentration. Stress analysis indicated severe stress singularities at the edges of the contact zone, which facilitated cycle slip and fatigue crack nucleation. Recommendations were also made for improving the fatigue performance of the suspension springs.</p></div>","PeriodicalId":91224,"journal":{"name":"Case studies in engineering failure analysis","volume":"2 2","pages":"Pages 169-173"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.csefa.2014.08.001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"54176737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 58
Failure analysis of a burner ring made of 20Cr32Ni1Nb alloy in gas turbine combustion chamber 燃气轮机燃烧室20Cr32Ni1Nb合金燃烧器环失效分析
Case studies in engineering failure analysis Pub Date : 2014-10-01 DOI: 10.1016/j.csefa.2014.07.001
Sahand Kargarnejad, Vahid Abbasi-Chianeh
{"title":"Failure analysis of a burner ring made of 20Cr32Ni1Nb alloy in gas turbine combustion chamber","authors":"Sahand Kargarnejad,&nbsp;Vahid Abbasi-Chianeh","doi":"10.1016/j.csefa.2014.07.001","DOIUrl":"10.1016/j.csefa.2014.07.001","url":null,"abstract":"<div><p>The failure analysis of an insert ring of a burner in a 156<!--> <!-->MW gas turbine made of 20Cr32Ni1Nb alloy is presented. Normally, the useful service life of these parts under ideal conditions is about 30,000<!--> <!-->h. However, more likely fracture and failure could be observed in 5000-h inspections, which resulted in the early and premature replacement of these parts.</p><p>Microstructural changes of the alloy were carefully examined after utilization by means of optical microscopy and scanning electron microscopy (SEM). An increase of Nb element in carbides and dissolution of secondary interdendritic carbides after 5000<!--> <!-->h of operation were observed. The studies indicate that the most damaging factors are the adverse working conditions and thermal stresses.</p></div>","PeriodicalId":91224,"journal":{"name":"Case studies in engineering failure analysis","volume":"2 2","pages":"Pages 138-143"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.csefa.2014.07.001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"54176704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 7
Failure analysis of air cooled condenser gearbox 风冷冷凝器齿轮箱失效分析
Case studies in engineering failure analysis Pub Date : 2014-10-01 DOI: 10.1016/j.csefa.2014.08.003
Anand Parey, N.K. Jain, S.C. Koria
{"title":"Failure analysis of air cooled condenser gearbox","authors":"Anand Parey,&nbsp;N.K. Jain,&nbsp;S.C. Koria","doi":"10.1016/j.csefa.2014.08.003","DOIUrl":"10.1016/j.csefa.2014.08.003","url":null,"abstract":"<div><p>Gears are very reliable components and normally work 5–6 years without failure. This article is a case study of failure analysis of a gearbox which was failed in three months after its installation. The problem was identified by maintenance engineers through vibration monitoring of gearbox. Hardness measurement of case and core revealed that the core was harder than case and the applied load was sufficiently high for failure of gear. Recommendations were given to improve the fatigue life of gearbox.</p></div>","PeriodicalId":91224,"journal":{"name":"Case studies in engineering failure analysis","volume":"2 2","pages":"Pages 150-156"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.csefa.2014.08.003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"54176755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 13
Fracture of a veneered-ZrO2 dental prosthesis from an inner thermal crack 贴面zro2牙修复体内部热裂纹断裂
Case studies in engineering failure analysis Pub Date : 2014-10-01 DOI: 10.1016/j.csefa.2014.06.003
Ulrich Lohbauer , Renan Belli , Gerwin Arnetzl , Susanne S. Scherrer , George D. Quinn
{"title":"Fracture of a veneered-ZrO2 dental prosthesis from an inner thermal crack","authors":"Ulrich Lohbauer ,&nbsp;Renan Belli ,&nbsp;Gerwin Arnetzl ,&nbsp;Susanne S. Scherrer ,&nbsp;George D. Quinn","doi":"10.1016/j.csefa.2014.06.003","DOIUrl":"10.1016/j.csefa.2014.06.003","url":null,"abstract":"<div><p>Here we describe the fractographic analysis of a veneer-ZrO<sub>2</sub> single-unit dental prosthesis that fractured in a shell-like manner. Analysis of the retrieved fragment revealed that the crack originated in the bulk of the veneer from a thermal flaw located between two layers of the veneering material. Using the measured flaw plane we showed that the conditions of loading at fracture were complex and probably involved important tangential components.</p></div>","PeriodicalId":91224,"journal":{"name":"Case studies in engineering failure analysis","volume":"2 2","pages":"Pages 100-106"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.csefa.2014.06.003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"54176686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 12
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信