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Fluid Dynamics & Materials Processing 2023年第2期19卷 329-344页

作者： Lingyun Zhao Heng Yang Yuanlong Wei Yuhuan Bu Shaorui Jing Peiming Zhou Key Laboratory of Unconventional Natural Gas Evaluation and Development in Complex Tectonic Areas Ministry of Natural ResourcesGuiyang550081China Guizhou Engineering Research Institute of Oil&Gas Exploration and Development Guiyang550081China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580China Shandong Key Laboratory of Oilfield Chemistry Key Laboratory of Unconventional Oil&Gas DevelopmentChina University of Petroleum(East China)Qingdao266580China

Perforation and fracturing are typically associated with the development of coalbed methane wells.As the cement sheath is prone to failure during this process,in this work,the effects of the casing pressure,elastic modulus of the cement,elastic modulus of the formation,and casing eccentricity on the resulting stresses are analyzed in the frame of a finite element method.Subsequently,sensitivity response curves of the cement sheath stress are plotted by normalizing all factors.The results show that the maximum circumferential stress and Mises stress of the cement sheath increase with the casing internal pressure,elastic modulus of the cement and casing eccentricity.As the elastic modulus of the formation increases,the maximum circumferential stress of the cement sheath decreases,and its maximum Mises stress increases slightly.The cement sheath undergoes tensile failure during coalbed methane fracturing.The stress sensitivity of the cement sheath to the influential parameters is in the following order:casing internal pressure>elastic modulus of cement sheath>casing eccentricity>elastic modulus of formation.

关键词： Coalbed methane fracturing finite element method cement sheath integrity sensitivity analysis failure analysis

Quality assurance test and failure analysis of SiPM arrays of GECAM satellites

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Radiation Detection Technology and Methods 2022年第1期6卷 35-42页

作者： D.L.Zhang M.Gao X.L.Sun X.Q.Li Z.H.An X.Y.Wen C.Cai Z.Chang G.Chen C.Chen Y.Y.Du R.Gao K.Gong D.Y.Guo J.J.He D.J.Hou Y.G.Li C.Y.Li G.Li L.Li X.F.Li M.S.Li X.H.Liang X.J.Liu Y.Q.Liu F.J.Lu H.Lu B.Meng W.X.Peng F.Shi H.Wang J.Z.Wang Y.S.Wang H.Z.Wang X.Wen S.Xiao S.L.Xiong Y.B.Xu Y.P.Xu S.Yang J.W.Yang Fan.Zhang S.N.Zhang C.Y.Zhang C.M.Zhang Fei Zhang X.Y.Zhao X.Zhou Institute of High Energy Physics CASBeijing 100049People’s Republic of China

Background The Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(GECAM)satellite developed a SiPM-based gamma-ray detector to monitor the gravitational wave-related GRBs and guide subsequent observations in other wavelengths of EM.Purpose As all the available SiPM devices belong to commercial grade,quality assurance tests need to be performed in accordance with the aerospace specifcations.Methods In the SiPM application of GECAM,quality assurance experiments were conducted.The mechanism of the failure of SiPM devices was analyzed during the development process.Result Based on the quality assurance test results,the fnal pass rate of SiPM array was 95%.Based on the failure analysis,it was found that a piece of SiPM had a leakage channel after longtime operation due to device defects.Conclusion According to the accumulated experience,in the reliability test of SiPM,it is necessary to pay special attention to test the impedance of each pin of SiPM to ground and confrm that the power switch state of SiPM is controllable.

关键词： Gravitational waves Gamma-ray detectors Silicon photomultipliers Quality assurance test failure analysis

failure analysis of 18CrNi3MoA drilling tails

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International Journal of Minerals,Metallurgy and Materials 2012年第5期19卷 421-427页

作者： Hong-wu Zhu Ya-zheng Liu Le-yu lhobl Lei-ying Wang Bin Huang School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Xining Special Steel Co. Ltd. Xining 810005 China

The fracture of a drilling tail made of 18CrNi3MoA steel in the exchanging water hole was analyzed in terms of inclusions, prior austenite grain size, carburized layers, and fatigue fracture morphology by means of optical microscopy, quantitative metallography, and scanning electron microscopy （SEM）. Fatigue crack initiation and propagation on the drilling tail were also studied. The results showed that the fracture on the drilling tail was not induced by inclusions and the distribution inhomogeneity of prior austenite grain size. Instead, be- cause the outside surface of the exchanging water hole was not continuously geometric, there was a great deal of stress concentration in those areas under continuous twisting, axial impact, and corrosion of mineral water. Thus three crack sources emerged in these areas. Initial cracks centered on these sources spread from the outside surface to the inside surface, and eventually the drilling tail ruptured. Furthermore, the fractograph of the region around the crack sources exhibited a typical ductile dimple fracture pattern, and cracks initiated on the outside sur- face of the carburized layers of the exchanging water hole. Three crack sources could be the sources of fatigue crack propagation. Based on the analysis of fatigue crack propagation, it was further demonstrated that fatigue damage originated from the outside surface of the ex- changing water hole.

关键词： drilling tools failure analysis crack initiation crack propagation

failure analysis of AZ31 magnesium alloy sheets based on the extended GTN damage model

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International Journal of Minerals,Metallurgy and Materials 2013年第12期20卷 1198-1207页

作者： Rui-ze Wang Zhang-hua Chen Yu-jie Li Chao-fang Dong School of Mathematics and Physics University of Science and Technology Beijing Xi’an Research Institute Co. Ltd.China Coal Technology & Engineering Group Crop. School of Material Engineering University of Science and Technology Beijing

Based on the Gurson-Tvergaard-Needleman （GTN） model and Hill＇s quadratic anisotropic yield criterion, a combined experimental-numerical study on fracture initiation in the process of thermal stamping of Mg alloy AZ31 sheets was carried out. The aim is to predict the formability of thermal stamping of the Mg alloy sheets at different temperatures. The presented theoretical framework was implemented into a VUMAT subroutine for ABAQUS/EXPLICIT. Internal damage evolution due to void growth and coalescence developed at different temperatures in the Mg alloy sheets was observed by scanning electron microscopy （SEM）. Moreover, the thermal effects on the void growth, coalescence, and fracture behavior of the Mg alloy sheets were analyzed by the extended GTN model and forming limit diagrams （FLD）. Parameters employed in the GTN model were determined from tensile tests and numerical iterative computation. The distribution of major and minor principal strains in the specimens was determined from the numerical results. Therefore, the corresponding forming limit diagrams at different stress levels and temperatures were drawn. The comparison between the predicted forming limits and the experimental data shows a good agreement.

关键词： magnesium alloys failure analysis microstructure anisotropy stamping

Review on failure analysis of interconnections in power devices

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China Welding 2022年第1期31卷 6-14页

作者：黄伟陈志文 School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China The Institute of Technological Sciences Wuhan UniversityWuhan 430064China Tsinghua Innovation Center in Zhuhai Zhuhai 519099China

Interconnections in microelectronic packaging are not only the physical carrier to realize the function of electronic circuits,but also the weak spots in reliability tests.Most of failures in power devices are caused by the malfunction of interconnections,including failure of bonding wire as well as cracks of solder layer.In fact,the interconnection failure of power devices is the result of a combination of factors such as electricity,temperature,and force.It is significant to investigate the failure mechanisms of various factors for the failure analysis of interconnections in power devices.This paper reviews the main failure modes of bonding wire and solder layer in the interconnection structure of power devices,and its failure mechanism.Then the reliability test method and failure analysis techniques of interconnection in power device are introduced.These methods are of great significance to the reliability analysis and life prediction of power devices.

关键词： power device reliability test failure analysis interconnection

failure analysis AND INSPECTION OF CRACKING OF IN-SERVICE CATALYTIC REGENERATOR

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Chinese Journal of Mechanical Engineering 2002年第2期15卷 167-172页

作者： Chen Xuedong Guan Weihe Chen Wenhu Yao Zuoquan Hefei General Machinery Research Institute, Hefei 230031, ChinaGu Xuedong Wang Zhaowei Shanghai Gaoqiao Petrochemical Company Zuoquan Hefei General Machinery Research Institute Hefei 230031 Shanghai Gaoqiao Petrochemical Company

The special subject 'research on life prediction technology of important in-service pressure' mainly analyzes the failure mechanism of large-sized important and criticalin-service pressure vessels under the action of working medium and investigates safety assessmentand life prediction technology with a view to enhance the operation reliability of in-servicepressure vessels in China. Based on a series of accident investigation and test & measuringresearch, the cause of cracking of catalytic regenerator is analyzed and the in-line non-destructiveexamination method and failure prevention measures for the cracking of catalytic regenerator areproposed.

关键词： In-service catalytic regenerator Crack failure analysis Examination

Macro Meso Response and Stress Wave Propagation Characteristics of MCT High-Voltage Switch Under Shock load

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Defence Technology（防务技术） 2024年第2期32卷 317-335页

作者： Yuyang Guo Chuang Chen Ruizhi Wang Enling Tang Key Laboratory of Transient Physical Mechanics and Energy Conversion Materials of Liaoning Province Shenyang Ligong UniversityShenyang110159LiaoningChina

In order to study the dynamic and electrical coupling response characteristics of Metal Oxide Semiconductor Controlled Thyristor(MCT)high-voltage switch under the synergic action of mechanical load and high voltage,the separated Hopkinson pressure bar(SHPB)test system was used to simulate different impact load environments,and combined with the multi-layer high-voltage ceramic capacitor charging and discharging system,the instantaneous electrical signals of MCT high-voltage switch were collected.Combined with numerical simulation and theoretical analysis,the failure mode and stress wave propagation characteristics of MCT high voltage switch were determined.The mechanical and electrical coupling response characteristics and failure mechanism of MCT high voltage switch under dynamic load were revealed from macroscopic and microscopic levels.The results show that the damage modes of MCT high-voltage switches can be divided into non-functional damage,recoverable functional damage,non-recoverable damage and structural damage.Due to the gap between the metal gate and the oxide layer,the insulating oxide layer was charged.After placing for a period of time,the elastic deformation of the metal gate partially recovered and the accumulated charge disappeared,which induced the recoverable functional damage failure of the device.In addition,obvious cracks appeared on both sides of the monocrystalline silicon inside the MCT high-voltage switch,leading to unrecoverable damage of the device.

关键词： MCT Impact load failure analysis Stress wave Numerical simulation

failure analysis of Austenitic Stainless Steel Implant Screws and Prospection of Chemical Composition Using Artificial Intelligence

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World Journal of Engineering and Technology 2022年第1期10卷 98-118页

作者： Alfonso Monzamodeth Román-Sedano Bernardo Campillo Fermín Castillo Osvaldo Flores Facultad de Química Universidad Nacional Autónoma de México Ciudad de México México Instituto de Ciencias Físicas Universidad Nacional Autónoma de México Cuernavaca Morelos México

In this work, austenitic stainless steel screws employed in a locking compression plate for veterinarian use were investigated. These types of implants are widely utilized in bone fractures healing. Two surgical screws were extracted due to the observation of slight superficial red rust colorizing on one of the screw implants, visual evidence of probable screw rusting. From the same implant, another screw was extracted simultaneously without visual evidence of rusting. In order to characterize and analyze the different behavior of both screws, the chemical composition was characterized by atomic absorption and energy dispersive X-ray spectroscopy (EDS) coupled to a scanning electron microscope (SEM). Also, the screws were studied by metallography, optical microscopy (OM), Vickers microhardness tests, and SEM analysis. On the other hand, a prospection for alloy chemical composition limits of these types of implants was performed based on the Schaeffler-Delong diagram and the ASTM F-138 standard. To analyze the effect of the chemical composition, heat treatment, microstructure, pitting resistance equivalent number (PRE) and stacking fault energy (SFE), a genetic algorithm (GA) and an artificial neural network (ANN) were used. In accordance with the elemental analysis, the surgical screws do not fulfill the ranges of the chemical composition established by the ASTM F-138 standard. Furthermore, there were found differences between the microstructures of the screws. In regard to the prospection, the results of GA and ANN support the proposed chemical composition region on the Schaeffler-Delong diagram. The corrosion failure was associated with severe plastic deformation and the presence of precipitates. The proposal can minimize the cause of failures in these types of austenitic stainless steel implants.

关键词： Implant Screw failure analysis Genetic Algorithm Artificial Neural Network Austenitic Stainless Steel

failure analysis of the needle valve body of R18CrNi8 steel

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Baosteel Technical Research 2023年第4期17卷 41-46页

作者： HUANG Rui LIU Xiangjiang HUANG Zongze Research Institute Baoshan Iron&Steel Co.Ltd.Shanghai 201999China

A needle valve is a key component of a diesel injector.The needle valve body of the diesel engine, made of R18CrNi8 steel, cracked and failed during the working process.The cracking failure reasons for the carburized injector valve body through chemical composition analysis, metallographic examination, scanning electron microscope(SEM) analysis, and energy spectrum analysis, were investigated.The results reveal that the original material of the needle valve is in conformity with the manufacturing requirement.Due to the high carburizing quenching temperature, the best carburized layer structure was not obtained, and the machining defect from which the crack emanated was not identified.The cracks expanded and eventually led to fracture under the action of altered stress and the high-temperature combustion environment during the operation of the engine.

关键词： injector valve body failure analysis R18CrNi8 steel