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A Review on Distortion and residual stress in Additive Manufacturing

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Chinese Journal of Mechanical Engineering(Additive Manufacturing Frontiers) 2022年第3期1卷 58-68页

作者： Deqiao Xie Fei Lv Youwen Yang Lida Shen Zongjun Tian Cijun Shuai Bo Chen Jianfeng Zhao College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing210016China College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing210016China Institute of Bioadditive Manufacturing Jiangxi University of Science and TechnologyNanchang330044China School of Engineering University of LeicesterLeicesterLE17RHUK

Additive manufacturing(AM)has gained extensive attention and tremendous research due to its advantages of fabricating complex-shaped parts without the need of casting mold.However,distortion is a known issue for many AM technologies,which decreases the precision of as-built parts.Like fusion welding,the local high-energy input generates residual stresses,which can adversely affect the fatigue performance of AM parts.To the best of the authors’knowledge,a comprehensive review does not exist regarding the distortion and residual stresses dedicated for AM,despite some work has explored the interrelationship between the two.The present review is aimed to fill in the identified knowledge gap,by first describing the evolution of distortion and residual stresses for a range of AM processes,and second assessing their influencing factors.This allows us to elucidate their formation mechanisms from both the micro-and macro-scales.Moreover,approaches which have been successfully adopted to mitigate both the distortion and residual stresses are reviewed.It is anticipated that this review paper opens many opportunities to increase the success rate of AM parts by improving the dimension precision and fatigue life.

关键词： Additive manufacturing Distortion residual stress Selective laser melting Laser melting deposition

Analysis of residual stress distribution along interface asperity of thermal barrier coating system on macro curved surface

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Progress in Natural Science:Materials International 2011年第3期21卷 262-267页

作者： Ming SONG,Yue MA,Sheng-kai GONG Key Laboratory of Aerospace Materials and Performance(Ministry of Education), School of Materials Science and Engineering,Beihang University,Beijing 100191,China Key Laboratory of Aerospace Materials and Performance (Ministry of Education) School of Materials Science and Engineering Beihang University Beijing 100191 China

Based on the study of the radial residual stress distribution on the macro curved interfaces of thermal barrier coating system(TBCs) for the hollow curved substrate structures,the hollow four-concentric-circle model was developed.And the concentric-circle model with a fine scaled sinusoidal interface was proposed to describe the stresses distribution on the rough interface of TBCs with macro curved geometry.The influences of the geometric and thermophysical parameters were discussed by the developed model.The results showed that the radial stress on the rough interface can be separated into two sections:the overall level stress from macro surface curvature and the local stress from local asperity of the interface.The overall level stress was determined by the thicknesses and the thermophysical parameters of each layer.It has been found that the ratio of local stress and overall level stress was influenced by the interface asperity,the ratio of elastic modulus and the ratio of thermal expansion coefficients of the layers beside the rough interface.Furthermore,the convex macro curvature of the substrate can induce tensile stress onto the interface.Especially at the sharp corners of the substrate,the small curvature radius can cause high stress which should be taken more care about the occurrence of spalling cracking at interface

关键词： barrier coating system(TBC) residual stress interface asperity thermal grown oxide(TGO) concentric-circle model

Effect of Grinding and Polishing on the residual stress and Bending Strength of a Silicon Nitride Ceramic

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Journal of Wuhan University of Technology(Materials Science) 2005年第1期20卷 46-48页

作者：高玲 State Key Lab of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

The residual stresses on the surface of the d ifferently ground and polished silicon nitride ceramics were measured using X-r ay diffraction and identified by SEM.The effect of the residual stress on the be nding strength was investigated.The investigations show that the grinding proces s can introduce subatantial tensile residual stresses up to 290MPa on the surfac e of silicon nitride ceramics,which has a significant effect on reducing the ben ding strength of the ceramics after grinding.Thus,in comparison with the ceramic s with a rough surface,the ceramics with a mirror image surface may have a lower strength.Polishing can smooth the residual stresses.When we evaluate the qualit y of the ceramic components after grinding,we must take residual stress into con sideration. The grinding methods and grinding conditions must be carefully selec ted in order to get the favorite residual stress as well as the surface smoothne ss.

关键词： residual stress grinding bending strengt h ceramics

Measurement and Analysis on Hardness and residual stress of Heavy Forging after Heat Treatment

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Journal of Iron and Steel Research(International) 2002年第1期9卷 58-61页

作者： ZHANG Hai Yanshan University

The hardness and residual stress in the forging for cold roller during low temperature tempering,and the relationship of residual stress and cooling temperature of high temperature tempering for heavy forgings were studied.The stress relaxation constant at low temperature tempering and the elasto-plastisity inversion temperature at high temperature tempering were found.The results are of great importance to determine rational tempering cooling process of heavy forgings.

关键词： heavy forging heat treatment tempering hardness residual stress measurement

An Overview of Techniques for Measuring residual stress in Metal Matrix Composites

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Journal of Materials Science and Chemical Engineering 2022年第10期10卷 59-77页

作者： Qingping Wang Pakeeza Maryum Yuxin Liu School of Materials Science and Engineering Anhui University of Science and Technology Huainan China State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines Anhui University of Science and Technology Huainan China

Measurement of residual stress is signiﬁcant to ensure safety, reliability and the life of composites, and currently has been a hot issue in scientiﬁc research. The fabrication processes such as machining, and heat treatment inherit either kind of residual stress which had either positive consequences or negative ones, for example, the fatigue limit of a component enhances by compressive stress, whereas corrosion resistance gets reduced by tensile stress. This study is aimed at a brief overview of the recent advancement in this field to help researchers in the in-depth study of measuring residual stress. It helps them in selecting the most appropriate techniques among destructive methods i.e., mainly Contour, ring core, deep hole-drilling method, and non-destructive techniques i.e., diffraction, ultrasonic method, depending on their requirements and applications. For each available technique, working methodology, physical limitations, and applications are discussed. At the end of this paper, future trends regarding an assessment of residual stress have been forecasted.

关键词： residual stress Destructive Methods Compressive residual stress Tensile residual stress Non-Destructive Methods

EFFECT OF residual stress ON THE MARTENSITIC TRANSFORMATION OF SPUTTER-DEPOSITED SMA THIN FILMS

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Acta Metallurgica Sinica(English Letters) 2002年第4期15卷 391-395页

作者： L.Wang,D.Xu and B.C.CaiInformation Storage Research Center, Shanghai Jiao Tong University, Shanghai 200030, China Manuscript received 14 September 2001 in revised form 27 November 2001 Info. Storage Res. Cent. Shanghai Jiaotong Univ. Shanghai 200030 China

TiNi thin films were sputter-deposited on circular single-crystal silicon substrates un-der various sputtering parameters. The crystal structure and residual stress of the as-deposited films were determined by X-ray diffraction and substrate-curvature method. The phenomenon of stress-suppressed martensitic transformation was observed. R is considered that the residual stresses in SMA thin films based on circular substrates act as balanced biaxial tensile stresses. The status of equilibrant delays the align-ment of self-accommodated variants and the volume shrinkage during the martensitic transformation.

关键词： martensitic transformation residual stress TiNi thin film shape memory alloy

Effect of Al_2O_3 Content on residual stress and Proper-ties of CAS Glass-ceramics

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Journal of Wuhan University of Technology(Materials Science) 2008年第6期23卷 889-892页

作者：谢俊 Key Laboratory of Silicate Materials Science and Engineering (Wuhan University of Technology) Ministry of Education Wuhan University of Technology

The structure and properties of the glass-ceramics were tested with X-ray diffraction testing instrument,correlative software,and other modern testing means.Then the effect of Al2O3 content on internal stresses in CaO-Al2O3-SiO2 glass-ceramics was studied deeply.In order to study the relationship of Al2O3 to the residual stress of CaO-Al2O3-SiO2 glass-ceramics,X-ray diffraction ＂sin2ψ＂ was used.The means utilized the x radial incidence produced from cathode radial tube,and took the space between crystals as measurement of strain.When the stresses produced,the space between crystals changed and the diffraction peak moved during Bragg diffraction.The magnitude of movement is related to the stresses.The experimental results show the residual stress is considerably high and Al2O3 can influence the mechanical properties of this material hugely.

关键词： residual stress Cao-A1203-SiO2 glass-ceramic X-ray diffraction crystallization temperature

Literature Review of Electronic Packaging Technology and residual stress

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Open Journal of Applied Sciences 2023年第11期13卷 2172-2182页

作者： Wenji Ai Shanshui Zheng Xianfeng Zeng Huibing Cheng Guangzhou Railway Polytechnic Guangzhou China

The rapid development of the electronic information industry brings to the irreplaceable role of electronic components, therefore the search of a more reliable packaging material has become increasingly important. In the electronic packaging system, the failure phenomenon caused by residual stress is one of the key factors restricting the development of electronic packaging technology. In order to use the in-situ characterization technology to explore the residual stress inducing mechanism and failure mechanism of epoxy-based advanced packaging materials, this paper gives a review of related previous research, and lays a theoretical foundation for the upcoming research. The classification and generation mechanism of residual stress are clarified in this paper, which provides data support for future related research.

关键词： Electronic Packaging Material residual stress Epoxy Failure Mechanisms

Mechanism investigation and strategies for reducing residual stress at open ends of the roll-formed part

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宝钢技术研究:英文版 2023年第3期17卷 25-31页

作者： XU Dongkai SHI Lei XIAO Hua Research Institute Baoshan Iron&Steel Co.Ltd.Shanghai 201999China State Key Laboratory of Development and Application Technology of Automotive Steels(Baosteel) Shanghai 201999China

Increasing geometrical accuracy at open ends of the roll-formed part is difficult due to the release of residual stress after end cutting.In this work,a typical rail with a high requirement of geometry accuracy was selected to realize the behaviors of residual stress release.First,residual stress distribution after roll forming is discussed in detail by finite element analysis with ABAQUS.In addition,two different approaches are proposed to check their capabilities in reducing the residual stress level.The results indicate that both additional rolling passes and multiple bending processes are beneficial to reducing uniform residual stress.

关键词： roll forming ultra-high-strength steel residual stress