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Multi-field dynamic modeling and numerical simulation of aluminum alloy resistance spot welding 被引量:1
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作者 陶建峰 贡亮 +1 位作者 刘成良 赵阳 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第12期3066-3072,共7页
In order to explore the influence of welding parameters and to investigate the Al alloy (AA) nugget formation process, a comprehensive model involving electrical-thermal-mechanical and metallurgical analysis was estab... In order to explore the influence of welding parameters and to investigate the Al alloy (AA) nugget formation process, a comprehensive model involving electrical-thermal-mechanical and metallurgical analysis was established to numerically display the resistance spot welding (RSW) process within multiple fields and understand the AA-RSW physics. A multi-disciplinary finite element method (FEM) framework and a empirical sub-model were built to analyze the affecting factors on weld nugget and the underlying nature of welding physics with dynamic simulation procedure. Specifically, a counter-intuitive phenomenon of the resistance time-variation caused by the transient inverse virtual variation (TIVV) effect was highlighted and analyzed on the basis of welding current and temperature distribution simulation. The empirical model describing the TIVV phenomenon was used for modifying the dynamic resistance simulation during the AA spot welding process. The numerical and experimental results show that the proposed multi-field FEM model agrees with the measured AA welding feature, and the modified dynamic resistance model captures the physics of nugget growth and the electrical-thermal behavior under varying welding current and fluctuating heat input. 展开更多
关键词 resistance spot welding aluminum alloy multi-field modeling simulation finite element method dynamic resistance transient inverse virtual variation effect
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Study of joining mechanism of ABS polymer and steel/aluminum by resistance spot welding 被引量:9
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作者 Zhang Changqing Lu Guangming +2 位作者 Jin Xin Wang Weijie Jin Shaolong 《China Welding》 EI CAS 2018年第2期57-62,共6页
The joining of metal and polymer is an increasingly important method to get lightweight components in the development of manufacturing industry- nowadays. In this artiele, metal and polymer lap joint was achieved by m... The joining of metal and polymer is an increasingly important method to get lightweight components in the development of manufacturing industry- nowadays. In this artiele, metal and polymer lap joint was achieved by means of resistance spot welding (RSW) and ultrasonic assistance welding (UAW). The joining mechanism of lap joint was analyzed by OM, TEM on microstructure at the interface of lap joints and XPS and IR spectra was discussed based on the following different ones: mechanical-interlocking, diffusion bond and coordination bond. The results showed that it was the combined action that played an important role in the effective joining work. Besides, ultrasonic assistance was used in the study to aid welding process based on its high-frequency ultrasonic vibration, which made joints shaping better and improved tensile strength visibly contrast to joints with the same lower heat input parameters. 展开更多
关键词 lap joints resistance spot welding joining mechanism ultrasonic assistance welding
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Numerical simulation on temperature field for resistance spot welding of non-equal thickness stainless steel 被引量:8
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作者 王春生 陈勇 +2 位作者 韩凤武 陆培德 姜中辉 《China Welding》 EI CAS 2003年第1期6-10,共5页
An axisymmetric finite element model is developed to simulate the temperature field of resistant spot welding according to the process characters of nugget formation of non equal stainless steel sheets. A simulation ... An axisymmetric finite element model is developed to simulate the temperature field of resistant spot welding according to the process characters of nugget formation of non equal stainless steel sheets. A simulation method of the interaction of electrical and thermal factors is presented. The spot welding process of nugget formation is simulated using hard and soft welding technique norms. The heating characters of soft and hard norms determine the differences in the process of nugget formation and determine the finally shape and offset of nugget. Experimental verification shows that the model prediction agrees well with the practical. 展开更多
关键词 resistance spot welding finite element temperature field numerical simulation
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Comparative study of resistance spot welding performance between cold-rolled DP980 and Q&P980 steels 被引量:5
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作者 LEI Ming 1,2) and PAN Hua 1,2) 1) Auto Steel Division,Research Institute,Baoshan Iron & Steel Co.,Ltd.,Shanghai 201900,China 2) State Key Laboratory of Development and Application Technology of Automotive Steels (Baosteel),Shanghai 201900,China 《Baosteel Technical Research》 CAS 2012年第1期37-40,共4页
Advanced high strength steel (AHSS) has been widely used in the automobile industry.The resistance spot welding performance of DP980 and Q&P980 steels was studied through comparing the two steels’welding current ... Advanced high strength steel (AHSS) has been widely used in the automobile industry.The resistance spot welding performance of DP980 and Q&P980 steels was studied through comparing the two steels’welding current range,tensile shear strength (TSS),cross tension strength (CTS),weld spots’microhardness,etc.The following conclusions were achieved:It is easy for both DP980 and Q&P980 steels to get a nugget size bigger than 4 mm,they all have welding current ranges exceeding 2 kA and high weld strength. 展开更多
关键词 AHHS DP980 Q&P980 resistance spot welding
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Numerical and Experimental Study on Nugget Formation Process in Resistance Spot Welding of Aluminum Alloy 被引量:2
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作者 罗震 颜福裕 +3 位作者 李洋 白杨 姚杞 谈辉 《Transactions of Tianjin University》 EI CAS 2015年第2期135-139,共5页
The weld nugget formation in the resistance spot welding(RSW) of aluminum alloy was investigated in the present study. The nugget formation process was directly observed by using a digital high-speed camera. Numerical... The weld nugget formation in the resistance spot welding(RSW) of aluminum alloy was investigated in the present study. The nugget formation process was directly observed by using a digital high-speed camera. Numerical simulation was also employed to investigate the nugget formation process. The results showed that for the RSW of two aluminum alloy sheets, a nugget was first formed in the workpiece/workpiece(W/W) interface and grew along the radial direction and axial direction of the sheets, and then it became a large elliptical nugget. For the RSW of three aluminum alloy sheets, two small nuggets were firstly formed in two W/W interfaces and grew along the axial direction and radial direction; finally they fused into one nugget. Besides, there existed a critical welding time, after which the nugget size remained nearly unchanged. This indicates that a long welding time is unnecessary for the RSW of aluminum alloy. In addition, the calculated nugget radius was compared with the experimental results, which showed that the simulation results agreed well with the experimental results. 展开更多
关键词 resistance spot welding aluminum alloy NUGGET formation high-speed PHOTOGRAPHY numerical simulation
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A MULTI-COUPLED FINITE ELEMENT ANALYSIS OF RESISTANCE SPOT WELDING PROCESS 被引量:3
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作者 Hou Zhigang Wang Yuanxun +1 位作者 Li Chunzhi Chert Chuanyao 《Acta Mechanica Solida Sinica》 SCIE EI 2006年第1期86-94,共9页
A two-dimensional axisymmetric finite element model is developed to analyze the transient thermal and mechanical behaviors of the Resistance Spot Welding (RSW) process using commercial software ANSYS. Firstly a dire... A two-dimensional axisymmetric finite element model is developed to analyze the transient thermal and mechanical behaviors of the Resistance Spot Welding (RSW) process using commercial software ANSYS. Firstly a direct-coupled electrical-thermal Finite Element Analysis (FEA) is performed to analyze the transient thermal characteristics of the RSW process. Then based on the thermal results a sequential coupled thermo-elastic-plastic analysis is conducted to determine the mechanical features of the RSW process. The thermal history of the whole process and the temperature distribution of the weldment are obtained through the analysis. The mechanical features, including the distributions of the contact pressure at both the faying surface and the electrode-workpiece interface, the stress and strain distributions in the weldment and their changes during the RSW process, the deformation of the weldment and the electrode displacement are also calculated. 展开更多
关键词 Finite Element Analysis (FEA) resistance spot welding (RSW) electrical-thermal coupling thermo-elastic-plastic analysis thermal behavior mechanical feature
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Interfacial microstructure and property of resistance spot welding joints of titanium to stainless steel 被引量:2
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作者 张晓娇 邱然锋 +2 位作者 张柯柯 代乐宜 石红信 《China Welding》 EI CAS 2013年第2期43-48,共6页
Commercially pure titanium and stainless steel sheets were welded using the technique of resistance spot welding with an aluminum alloy insert. The interfacial microstructure of the joint was observed and analyzed usi... Commercially pure titanium and stainless steel sheets were welded using the technique of resistance spot welding with an aluminum alloy insert. The interfacial microstructure of the joint was observed and analyzed using electron microscopy; the tensile shear strength was investigated. An approximate 160 nm thick layer of Al solid solution supersaturated with Ti was observed at the interface between titanium and aluminum alloy. The solid solution layer contained the precipitates TiAla. And an approximate 1. 5 μm thick serrate reaction layer was observed at the interface between stainless steel and aluminum alloy. The maximum tensile shear load of 5.38 kN was obtained from the joint welded at the welding current of 10 kA. The results reveal that the property of the joint between titanium and stainless steel can be improved by using an aluminum alloy insert. 展开更多
关键词 resistance spot welding TITANIUM stainless steel INTERFACE microstructure
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Filling technique for keyhole of friction stir spot welding based on the principles of resistance spot welding 被引量:3
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作者 Deng Lipeng Ke Liming Liu Jinhe 《China Welding》 EI CAS 2019年第3期34-41,共8页
Keyhole at the end of a weld prepared by friction stir welding(FSW)is one of the major issues that impede the application of FSW.To address this issue,a keyhole filling technique was proposed in this paper,which is ba... Keyhole at the end of a weld prepared by friction stir welding(FSW)is one of the major issues that impede the application of FSW.To address this issue,a keyhole filling technique was proposed in this paper,which is based on the principles of resistance spot welding(RSW).A three-phase secondary rectifier resistance spot welder was applied as the experimental instrument for filling the keyhole in the center of friction stir spot weld(FSSW).The test sheet is a 2024-T4 aluminium alloy with a thickness of 6.0mm.The experiments results show that the filled joint strength is improved by 26.12%since the area is increased for the plug in the keyhole.And there are two kinds of dimples in the tensile fracture-equiaxial dimples and long dimples.The filled joint involves the fusion welding zone(FWZ),pressure welding zone(PWZ),melted plug zone(MPZ),and plastic deformation zone(PDZ).The FWZ and the PWZ is the melting bond and diffusion bond between the plug and keyhole,respectively.The MPZ is the center part and the PDZ is upper or lower part of the plug. 展开更多
关键词 friction stir spot welding resistance spot welding KEYHOLE aluminum alloy
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Dynamic simulation of resistance spot welding of zinc-coated steels 被引量:2
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作者 王璐 王敏 卢凤桂 《China Welding》 EI CAS 2006年第4期39-42,共4页
A model was developed to simulate the temperature distribution and nugget formation during resistance spot welding ( RS1V) of zinc-coated steels. It employs a coupled thermal-electrical-mechanical analysis simulatin... A model was developed to simulate the temperature distribution and nugget formation during resistance spot welding ( RS1V) of zinc-coated steels. It employs a coupled thermal-electrical-mechanical analysis simulating the dynamic RSW process. Temperature-dependent thermal-electrical-mechanical material properties were considered including contact-resistance. The contact area was determined from a coupled thermal-mechanical analysis. A layer of transition elements was used to represent the change of contact area by killing or activating elements. The heat generation and temperature field were computed in a coupled thermal-electrical model. All these analyses were solved using the commercial finite element method (FEM) based on ANSYS code, and some advanced functions were used by writing a paragraph of codes by the authors. Compared with the results from only coupled thermal-electrical model in which contact area was uniform during the whole process, the result matches better to the experimental results. 展开更多
关键词 SIMULATION resistance spot welding zinc-coated steels thermal-mechanical analysis
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A cooperative control strategy of resistance spot welding process by combining the constant current control with the DRC method 被引量:2
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作者 李桂中 王长征 +1 位作者 孔萌 郭彩光 《China Welding》 EI CAS 2009年第2期25-29,共5页
The modeling control method based on the dynamic resistance characteristics of good nuggets, that is the DRC method, is an improvement on the dynamic resistance threshold method for the quality control of resistance s... The modeling control method based on the dynamic resistance characteristics of good nuggets, that is the DRC method, is an improvement on the dynamic resistance threshold method for the quality control of resistance spot welding. But there is still a control blind area in the initial four cycles. For this reason, the quality of every weld nugget could not be fully ensured. Thus a new fuzzy cooperative control method is put forward. It uses a multi-information time-control mechanism by combining the constant current control technology with the DRC method in a relay way. This whole-process control strategy has led to a good control effect and produced the dual-identical results in the weld nugget quality and the welding time. 展开更多
关键词 resistance spot welding control blind area nugget quality cooperative control strategy
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Quality estimation of resistance spot welding of stainless steel based on BP neural network 被引量:2
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作者 文静 张旭东 +3 位作者 徐国成 王春生 张小奇 何舒 《China Welding》 EI CAS 2009年第3期16-20,共5页
The end value of the dynamic resistance curve of stainless steel was proved to have strong correlation with nugget size by experiments, so it was an important factor for estimation of weld quality. BP neural network w... The end value of the dynamic resistance curve of stainless steel was proved to have strong correlation with nugget size by experiments, so it was an important factor for estimation of weld quality. BP neural network was employed to estimate the weld quality, The end value of the dynamic resistance curve, welding current and welding time were selected as the input variables while the nugget diameter, which is closely related to weld quality, was selected as the output variable. Testing results shows that such network has fine fault tolerance and real-time quality estimation is possible. 展开更多
关键词 resistance spot welding dynamic resistance BP neural network
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Reconstruction of Current Density Distribution in Weld Area During Resistance Spot Welding of Aluminum Alloy Based on Magnetic Field 被引量:1
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作者 单平 姚杞 +1 位作者 李洋 罗震 《Transactions of Tianjin University》 EI CAS 2015年第2期129-134,共6页
Magnetic flux density around the weld area was used to reconstruct the current density distribution during resistance spot welding(RSW) of aluminum alloy according to inverse problem theory. A current-magnetic field m... Magnetic flux density around the weld area was used to reconstruct the current density distribution during resistance spot welding(RSW) of aluminum alloy according to inverse problem theory. A current-magnetic field model was established and the conjugate gradient method was used to solve this model. The results showed that the current density was low at the center of nugget while high on the edge of nugget. Moreover, the welding time of 30ms—60 ms is a key period for nucleation. The current density distribution can reflect whether the weld nugget is formed or splashed, therefore it has the potential to monitor the weld quality of RSW. 展开更多
关键词 resistance spot welding current density distribution INVERSE problem magnetic field
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Effect of retained austenite and nonmetallic inclusions on the thermal/electrical properties and resistance spot welding nuggets of Si-containing TRIP steels 被引量:1
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作者 V.H.Vargas I.Mejía +1 位作者 V.H.Baltazar-Hernández C.Maldonado 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2019年第1期52-63,共12页
Five advanced high-strength transformation-induced plasticity(TRIP) steels with different chemical compositions were studied to correlate the retained austenite and nonmetallic inclusion content with their physical pr... Five advanced high-strength transformation-induced plasticity(TRIP) steels with different chemical compositions were studied to correlate the retained austenite and nonmetallic inclusion content with their physical properties and the characteristics of the resistance spot welding nuggets. Electrical and thermal properties and equilibrium phases of TRIP steels were predicted using the JMatPro? software. Retained austenite and nonmetallic inclusions were quantified by X-ray diffraction and saturation magnetization techniques. The nonmetallic inclusions were characterized by scanning electron microscopy. The results show that the contents of Si, C, Al, and Mn in TRIP steels increase both the retained austenite and the nonmetallic inclusion contents. We found that nonmetallic inclusions affect the thermal and electrical properties of the TRIP steels and that the differences between these properties tend to result in different cooling rates during the welding process. The results are discussed in terms of the electrical and thermal properties determined from the chemical composition and their impact on the resistance spot welding nuggets. 展开更多
关键词 transformation-induced plasticity steel RETAINED austenite non-metallic inclusions magnetic saturation electrical PROPERTIES THERMAL PROPERTIES resistance spot welding NUGGET
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Prediction and Verification of Resistance Spot Welding Results of Ultra-High Strength Steels through FE Simulations 被引量:2
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作者 Oscar Andersson Arne Melander 《Modeling and Numerical Simulation of Material Science》 2015年第1期26-37,共12页
Resistance spot welding (RSW) is the most common welding method in automotive engineering due to its low cost and high ability of automation. However, physical weldability testing is costly, time consuming and depende... Resistance spot welding (RSW) is the most common welding method in automotive engineering due to its low cost and high ability of automation. However, physical weldability testing is costly, time consuming and dependent of supplies of material and equipment. Finite Element (FE) simulations have been utilized to understand, verify and optimize manufacturing processes more efficiently. The present work aims to verify the capability of FE models for the RSW process by comparing simulation results to physical experiments for materials used in automotive production, with yield strengths from approximately 280 MPa to more than 1500 MPa. Previous research has mainly focused on lower strength materials. The physical weld results were assessed using destructive testing and an analysis of expulsion limits was also carried out. Extensive new determination of material data was carried out. The material data analysis was based on physical testing of material specimens, material simulation and comparison to data from literature. The study showed good agreement between simulations and physical testing. The mean absolute error of weld nugget size was 0.68 mm and the mean absolute error of expulsion limit was 1.10 kA. 展开更多
关键词 resistance spot welding FE Simulations High Strength Steel Material Modeling weld SIZE
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Deformation at Room and Low Temperatures and Martensite Transformation in Resistance Spot Welding Duplexγ&α(δ) Materials of 301L Stainless Steel 被引量:1
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作者 Wei LIU Jun HE +2 位作者 Meng FAN Peide LU Li SHAO 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2007年第3期319-322,共4页
Transformation induced plasticity (TRIP) and twinning induced plasticity (TWlP) effects had been widely studied in single austenite steel. But in duplex γ & α(δ) phase, such as welding materials of stainles... Transformation induced plasticity (TRIP) and twinning induced plasticity (TWlP) effects had been widely studied in single austenite steel. But in duplex γ & α(δ) phase, such as welding materials of stainless steel, they had been less studied. Tensile shear loading experiment of resistance spot welding specimens prepared with 2 mm 301L sheets, was carried out at 15℃ and -50℃. Optical microscopy and scanning electron microscopy (SEM) as well as X-ray diffraction (XRD) were used to investigate the microstructure of weld nugget, and specimens fracture surface. The results showed that the initial weld nugget was composed of 8.4% α(δ) ferrite and 91.6% austenite. Tensile shear load bearing capacity of spot welding specimen at -50℃ was 24.8 kN, 17.7% higher than that at 15℃. About 78.5 vol. pct. martensite transformation was induced by plastic deformation at -50℃, while about 67.9 vol. pct transformation induced at 15℃. The plasticity of spot welding joint decreased with the decline of experimental temperature. 展开更多
关键词 301L stainless steel resistance spot welding Duplex γ α(δ) Plastic deformation Martensite transformation
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Effect of welding current on strength and microstructure in resistance spot welding of AZ31 Mg alloy 被引量:1
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作者 王亚荣 张忠典 冯吉才 《China Welding》 EI CAS 2007年第4期37-41,共5页
In this paper, resistance spot welding were performed on lmm-thickness magnesium AZ31B plates. The effect of welding current on the microstructure and tensile shear force was investigated. It was found that the weldin... In this paper, resistance spot welding were performed on lmm-thickness magnesium AZ31B plates. The effect of welding current on the microstructure and tensile shear force was investigated. It was found that the welding current governed the nugget growth, and the nugget could not form if current levels were insufficient. The nugget revealed a homogeneous, equiaxed, fine-grained structure, which consisted of non-equilibrium microstructure of α-phase dendrites surrounded by eutectic mixtures of α and β( Mg17All2 ) in the grain boundaries. With increasing welding current, the size of grains in nugget would be more smaller and uniform, and the width of plastic rings would be larger. Tensile shear tests showed that tensile shear force of the joints increased with increasing welding current when the welding current was smaller than 17 000 A. The maximum tensile shear force was up to 1980 N. 展开更多
关键词 welding current MICROSTRUCTURE tensile shear force magnesium alloy resistance spot welding
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Measurement of dynamic resistance in resistance spot welding 被引量:1
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作者 武佩 吕佳珩 +1 位作者 Wenqi Zhang Niels Bay 《China Welding》 EI CAS 2007年第4期42-46,共5页
The conventional methods of determining the dynamic resistance were mostly done by measuring the voltage and current at secondary side of transformer in resistance welding machines, in which the measuring set-up norma... The conventional methods of determining the dynamic resistance were mostly done by measuring the voltage and current at secondary side of transformer in resistance welding machines, in which the measuring set-up normally interferes with the movement of electrode, and the measuring precision is influenced by inductive noise caused by the high welding current. In this study, the dynamic resistance is determined by measuring the voltage at primary side and current at secondary side. This increases the accuracy of measurement because of higher signal-noise ratio, and allows to apply to in-process system without any wires connected to electrodes. 展开更多
关键词 resistance spot welding dynamic resistance contact resistance circuit analysis
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On-line evaluating on quality of mild steel joints in resistance spot welding 被引量:1
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作者 张鹏贤 陈剑虹 《China Welding》 EI CAS 2008年第4期33-38,共6页
A method was developed to realize quality evaluation on every weld-spot in resistance spot welding based on information processing of artificial intelligent. Firstly, the signals of welding current and welding voltage... A method was developed to realize quality evaluation on every weld-spot in resistance spot welding based on information processing of artificial intelligent. Firstly, the signals of welding current and welding voltage, as information source, were synchronously collected. Input power and dynamic resistance were selected as monitoring waveforms. Eight characteristic parameters relating to weld quality were extracted from the monitoring waveforms. Secondly, tensile-shear strength of the spot-welded joint was employed as evaluating target of weld quality. Through correlation analysis between every two parameters of characteristic vector, five characteristic parameters were reasonably selected to found a mapping model of weld quality estimation. At last, the model was realized by means of the algorithms of Radial Basic Function neural network and sample matrixes. The results showed validations by a satisfaction in evaluating weld quality of mild steel joint on-line in spot welding process. 展开更多
关键词 resistance spot welding weld quality characteristic parameter quality evaluating Radial Basic Function neural network
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Electrical-thermal interaction simulation for resistance spot welding nugget process of mild steel and stainless steel 被引量:1
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作者 王春生 韩凤武 +3 位作者 陆培德 赵熹华 陈勇 邱冬生 《China Welding》 EI CAS 2002年第1期51-54,共4页
A three dimensional finite difference electrical thermal model for resistance spot welding nugget process of mild steel and stainless steel is introduced. A simulation method of the interaction of electrical and the... A three dimensional finite difference electrical thermal model for resistance spot welding nugget process of mild steel and stainless steel is introduced. A simulation method of the interaction of electrical and thermal factors is presented. Meanwhile, calculation method of contact resistance and treatment method of heater structure is provided. The influence of the temperature dependent material properties and various cooling boundary conditions on welding process was also taken into account in the model. A method for improving the mild steel and stainless steel joint was analyzed in numerical simulation process. Experimental verification shows that the model prediction agrees well with the practice. The model provides a useful theoretic tool for the analysis of the process of resistance spot welding of mild steel and stainless steel. 展开更多
关键词 mild steel stainless steel resistance spot welding finite difference numerical model
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Optimization design of resistance spot welding parameters of magnesium alloy 被引量:1
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作者 郎波 孙大千 +1 位作者 吴琼 宣兆志 《China Welding》 EI CAS 2008年第1期49-56,共8页
By means of the quadratic regression combination design process, the regression equations of nugget diameter and tensile shear load of spot welded joint were established. Effects of welding parameters on the nugget di... By means of the quadratic regression combination design process, the regression equations of nugget diameter and tensile shear load of spot welded joint were established. Effects of welding parameters on the nugget diameter and the tensile shear load were investigated. The results show that effect of welding current on nugget diameter is the most evident. And higher welding current will result in bigger nugget diameter. Besides, interaction effect of electrode force and welding current on tensile shear load is the most evident compared with others. The optimum welding parameters corresponding to the maximum of tensile shear load have been obtained by programming using Matlab software, which is 4, 7 kN electrode force, 28 kA welding current and 4 cycle welding time. Under the condition of the optimum welding parameters, the joint having no visible defects can be obtained, nugget diameter and tensile shear load being 6. 8 mm and 3 256 N, respectively. 展开更多
关键词 resistance spot welding magnesium alloy quadratic regression combination design welding parameter
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