The Experts below are selected from a list of 234 Experts worldwide ranked by ideXlab platform
Sven Jüttner - One of the best experts on this subject based on the ideXlab platform.
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Dissimilar metal joining of aluminum to steel by hybrid process of adhesive bonding and Projection Welding using a novel insert element
Journal of Materials Processing Technology, 2020Co-Authors: Anastasiia Zvorykina, Oleksii Sherepenko, Michael Neubauer, Sven JüttnerAbstract:Abstract Multi-material design offers cost-efficient lightweight solutions for automotive body-in-white production. It can be realized by joining ultra-high strength steels with aluminum alloys, using adhesive bonding, combined with another commonly used joining process. For these applications, processes like riveting, clinching, resistance spot Welding have been pushed to their technological limits and a further technological development is needed. The present research describes a new joining technology based on resistance Welding process for joining aluminum-silicon coated hot stamped ultra-high strength steel with aluminum. The technology consists of a two-stage Projection Welding process with an additional insert element. Its implementation allows joining aluminum and steel sheets using extremely short Welding time with high energy concentration in combination with adhesive bonding. Due to low heat input in the Welding process, the adhesive around the insert element is damaged significantly less, compared to classic resistance spot Welding. Depending on insert element size and orientation, short flanges can be joined, offering potential for further weight reduction of the car body. The elements are easily applicable under different production constraints. One of possible applications of the investigated joining process is Welding a thin outer aluminum sheet on a B-pillar. Welds were made using insert elements – cylinders of Cu- and Fe-based wires with diameter of 1.6 mm and length of 10 mm employing a medium frequency direct current resistance Welding machine. Both tested materials can be successfully used and the weld current ranges are sufficient for industrial application with and without the use of adhesive. Mechanical properties of joints, evaluated using tensile-shear tests, are comparable with those of the existing mechanical joining methods used in automobile manufacture.
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Novel Projection Welding technology for joining of steel-aluminum hybrid components—part 1: technology and its potential for industrial use
Welding in the World, 2020Co-Authors: Anastasiia Zvorykina, Oleksii Sherepenko, Sven JüttnerAbstract:Multi-material design offers cost-efficient lightweight solutions for automotive body-in-white production. Ultra-high strength steels remain an essential part of the lightweight construction and are increasingly used in combination with components made of aluminum alloys in multi-material body designs. For these applications, the commonly used joining processes (riveting, clinching, resistance spot Welding, etc.) have been pushed to their technological limits and a further technological development is needed. The present research describes a new joining technology based on resistance Welding process for joining ultra-high strength steel 22MnB5 (AS150) with aluminum sheets AW 6016. The technology consists of a two-stage resistance spot Welding process with an additional simple cost-effective joining element. Its implementation allows joining aluminum and steel on extremely short flanges of 10 mm using short time Projection Welding with high-energy concentration. Joining elements—cylinders made of Cu- and Fe-based wires with diameter 1.6 mm and length 10 mm - were welded using the common resistance spot Welding equipment. Experimental results have shown that all tested materials for joining dissimilar steel-aluminum compounds can be successfully used and the weld current ranges are sufficient for industrial application.
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novel Projection Welding technology for joining of steel aluminum hybrid components part 1 technology and its potential for industrial use
Welding in The World, 2020Co-Authors: Anastasiia Zvorykina, Oleksii Sherepenko, Sven JüttnerAbstract:Multi-material design offers cost-efficient lightweight solutions for automotive body-in-white production. Ultra-high strength steels remain an essential part of the lightweight construction and are increasingly used in combination with components made of aluminum alloys in multi-material body designs. For these applications, the commonly used joining processes (riveting, clinching, resistance spot Welding, etc.) have been pushed to their technological limits and a further technological development is needed. The present research describes a new joining technology based on resistance Welding process for joining ultra-high strength steel 22MnB5 (AS150) with aluminum sheets AW 6016. The technology consists of a two-stage resistance spot Welding process with an additional simple cost-effective joining element. Its implementation allows joining aluminum and steel on extremely short flanges of 10 mm using short time Projection Welding with high-energy concentration. Joining elements—cylinders made of Cu- and Fe-based wires with diameter 1.6 mm and length 10 mm - were welded using the common resistance spot Welding equipment. Experimental results have shown that all tested materials for joining dissimilar steel-aluminum compounds can be successfully used and the weld current ranges are sufficient for industrial application.
Wenqi Zhang - One of the best experts on this subject based on the ideXlab platform.
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Numerical and experimental analysis of resistance Projection Welding of square nuts to sheets
Procedia Engineering, 2015Co-Authors: Chris Valentin Nielsen, Wenqi Zhang, Paulo A.f. MartinsAbstract:Projection Welding of nuts to sheets is a widely utilized manufacturing process in the automotive industry. The process entails challenges due the necessity of joining different sheet thicknesses and nut sizes made from dissimilar materials, and due to the fact of experiencing large local deformations ranging from room temperature to above the melting point. Heating is facilitated by resistance heating and is highly influenced by the contact area resulting from the amount of deformation, which is also temperature dependent due to material softening and frictional conditions. Resort to new materials and applications require a new level of understanding of the process by combining finite element modelling and experimentation. This paper draws from the challenge of developing a three-dimensional computer program for electro-thermo-mechanical modeling of resistance Welding and presents, as far as the authors are aware, the first ever three-dimensional simulation of the Projection Welding of square nuts to sheets by means of finite element analysis. Results are compared with experimental observations and measurements produced by the authors with the aim and objective of assessing the accuracy, reliability and validity of the theoretical and numerical developments. Numerical simulations support the evaluation of the experiments by providing detailed information on the process like the initial heating location and the following temperature development, and allowing to analyze the weldability of the square nut to the sheet under different operating conditions.
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3d numerical simulation of Projection Welding of square nuts to sheets
Journal of Materials Processing Technology, 2015Co-Authors: Chris Valentin Nielsen, Wenqi Zhang, Paulo A.f. MartinsAbstract:Abstract The challenge of developing a three-dimensional finite element computer program for electro-thermo-mechanical industrial modeling of resistance Welding is presented, and the program is applied to the simulation of Projection Welding of square nuts to sheets. Results are compared with experimental observations and measurements produced by the authors with the aim and objective of assessing the accuracy, reliability and validity of the theoretical and numerical developments. The numerical developments include implementation of friction between deformable objects in the finite element flow formulation in order to model the frictional sliding between the square nut Projections and the sheets during the Welding process. It is proved that the implementation of friction increases the accuracy of the simulations, and the dynamic influence of friction on the process is explained.
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Contact Modelling in Resistance Welding. Part 2: Experimental Validation
Proceedings of the Institution of Mechanical Engineers Part B: Journal of Engineering Manufacture, 2006Co-Authors: Quanfeng Song, Wenqi ZhangAbstract:AbstractContact algorithms in resistance Welding presented in the previous paper are experimentally validated in the present paper. In order to verify the mechanical contact algorithm, two types of experiment, i.e. sandwich upsetting of circular, cylindrical specimens and compression tests of discs with a solid ring Projection towards a flat ring, are carried out at room temperature. The complete algorithm, involving not only the mechanical model but also the thermal and electrical models, is validated by Projection Welding experiments. The experimental results are in good agreement with the simulation prediction, showing the validity of the algorithm.
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Contact Modelling in Resistance Welding. Part 1: Algorithms and Numerical Verification
Proceedings of the Institution of Mechanical Engineers Part B: Journal of Engineering Manufacture, 2006Co-Authors: Quanfeng Song, Wenqi ZhangAbstract:AbstractFinite element based numerical modelling programs for resistance Welding are presently being improved as an important tool for development and optimization of complex joints. One of the remaining challenges in obtaining useful results is appropriate modelling of the contact between the parts. The contact problem in resistance Welding includes not only mechanical contact but also thermal and electrical contact. In this paper such a contact model is developed for simulation of resistance spot and Projection Welding. The mechanical contact includes frictionless contact as well as contact with sticking and with sliding friction. The thermal and the electrical contact are modelled by introducing an artificial contact layer. After a description of the algorithms, several numerical examples are presented to validate the mechanical contact algorithm.
Paulo A.f. Martins - One of the best experts on this subject based on the ideXlab platform.
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Numerical and experimental analysis of resistance Projection Welding of square nuts to sheets
Procedia Engineering, 2015Co-Authors: Chris Valentin Nielsen, Wenqi Zhang, Paulo A.f. MartinsAbstract:Projection Welding of nuts to sheets is a widely utilized manufacturing process in the automotive industry. The process entails challenges due the necessity of joining different sheet thicknesses and nut sizes made from dissimilar materials, and due to the fact of experiencing large local deformations ranging from room temperature to above the melting point. Heating is facilitated by resistance heating and is highly influenced by the contact area resulting from the amount of deformation, which is also temperature dependent due to material softening and frictional conditions. Resort to new materials and applications require a new level of understanding of the process by combining finite element modelling and experimentation. This paper draws from the challenge of developing a three-dimensional computer program for electro-thermo-mechanical modeling of resistance Welding and presents, as far as the authors are aware, the first ever three-dimensional simulation of the Projection Welding of square nuts to sheets by means of finite element analysis. Results are compared with experimental observations and measurements produced by the authors with the aim and objective of assessing the accuracy, reliability and validity of the theoretical and numerical developments. Numerical simulations support the evaluation of the experiments by providing detailed information on the process like the initial heating location and the following temperature development, and allowing to analyze the weldability of the square nut to the sheet under different operating conditions.
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3d numerical simulation of Projection Welding of square nuts to sheets
Journal of Materials Processing Technology, 2015Co-Authors: Chris Valentin Nielsen, Wenqi Zhang, Paulo A.f. MartinsAbstract:Abstract The challenge of developing a three-dimensional finite element computer program for electro-thermo-mechanical industrial modeling of resistance Welding is presented, and the program is applied to the simulation of Projection Welding of square nuts to sheets. Results are compared with experimental observations and measurements produced by the authors with the aim and objective of assessing the accuracy, reliability and validity of the theoretical and numerical developments. The numerical developments include implementation of friction between deformable objects in the finite element flow formulation in order to model the frictional sliding between the square nut Projections and the sheets during the Welding process. It is proved that the implementation of friction increases the accuracy of the simulations, and the dynamic influence of friction on the process is explained.
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All-hexahedral meshing and remeshing for multi-object manufacturing applications
Computer-aided Design, 2013Co-Authors: Chris Valentin Nielsen, J.l.m. Fernandes, Paulo A.f. MartinsAbstract:All-hexahedral meshing and remeshing algorithms giving support to finite element modeling of manufacturing processes require continuous development for improving its overall robustness and applicability. This paper draws from a previous all-hexahedral algorithm presented by the authors and proposes new developments related to the construction of adaptive core meshes and processing of multi-objects that are typical of manufacturing applications. Along with the aforementioned improvements there are other developments that will also be presented due to their effectiveness in increasing the robustness of all-hexahedral algorithms. These include identification and simplification of boundary features, reconstruction of vertices and edges with minimum element distortion, smoothing of nodal points along edges and topology based mesh repair procedures to ensure completeness of edge representation. The presentation is enriched with examples taken from pure geometry and metal forming applications, and a resistance Projection Welding industrial test case consisting of four different objects is included to show the capabilities of selective remeshing of objects while maintaining contact conditions and local geometrical details that are critical for electro-thermo-mechanical numerical simulations.
Anastasiia Zvorykina - One of the best experts on this subject based on the ideXlab platform.
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Dissimilar metal joining of aluminum to steel by hybrid process of adhesive bonding and Projection Welding using a novel insert element
Journal of Materials Processing Technology, 2020Co-Authors: Anastasiia Zvorykina, Oleksii Sherepenko, Michael Neubauer, Sven JüttnerAbstract:Abstract Multi-material design offers cost-efficient lightweight solutions for automotive body-in-white production. It can be realized by joining ultra-high strength steels with aluminum alloys, using adhesive bonding, combined with another commonly used joining process. For these applications, processes like riveting, clinching, resistance spot Welding have been pushed to their technological limits and a further technological development is needed. The present research describes a new joining technology based on resistance Welding process for joining aluminum-silicon coated hot stamped ultra-high strength steel with aluminum. The technology consists of a two-stage Projection Welding process with an additional insert element. Its implementation allows joining aluminum and steel sheets using extremely short Welding time with high energy concentration in combination with adhesive bonding. Due to low heat input in the Welding process, the adhesive around the insert element is damaged significantly less, compared to classic resistance spot Welding. Depending on insert element size and orientation, short flanges can be joined, offering potential for further weight reduction of the car body. The elements are easily applicable under different production constraints. One of possible applications of the investigated joining process is Welding a thin outer aluminum sheet on a B-pillar. Welds were made using insert elements – cylinders of Cu- and Fe-based wires with diameter of 1.6 mm and length of 10 mm employing a medium frequency direct current resistance Welding machine. Both tested materials can be successfully used and the weld current ranges are sufficient for industrial application with and without the use of adhesive. Mechanical properties of joints, evaluated using tensile-shear tests, are comparable with those of the existing mechanical joining methods used in automobile manufacture.
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Novel Projection Welding technology for joining of steel-aluminum hybrid components—part 1: technology and its potential for industrial use
Welding in the World, 2020Co-Authors: Anastasiia Zvorykina, Oleksii Sherepenko, Sven JüttnerAbstract:Multi-material design offers cost-efficient lightweight solutions for automotive body-in-white production. Ultra-high strength steels remain an essential part of the lightweight construction and are increasingly used in combination with components made of aluminum alloys in multi-material body designs. For these applications, the commonly used joining processes (riveting, clinching, resistance spot Welding, etc.) have been pushed to their technological limits and a further technological development is needed. The present research describes a new joining technology based on resistance Welding process for joining ultra-high strength steel 22MnB5 (AS150) with aluminum sheets AW 6016. The technology consists of a two-stage resistance spot Welding process with an additional simple cost-effective joining element. Its implementation allows joining aluminum and steel on extremely short flanges of 10 mm using short time Projection Welding with high-energy concentration. Joining elements—cylinders made of Cu- and Fe-based wires with diameter 1.6 mm and length 10 mm - were welded using the common resistance spot Welding equipment. Experimental results have shown that all tested materials for joining dissimilar steel-aluminum compounds can be successfully used and the weld current ranges are sufficient for industrial application.
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novel Projection Welding technology for joining of steel aluminum hybrid components part 1 technology and its potential for industrial use
Welding in The World, 2020Co-Authors: Anastasiia Zvorykina, Oleksii Sherepenko, Sven JüttnerAbstract:Multi-material design offers cost-efficient lightweight solutions for automotive body-in-white production. Ultra-high strength steels remain an essential part of the lightweight construction and are increasingly used in combination with components made of aluminum alloys in multi-material body designs. For these applications, the commonly used joining processes (riveting, clinching, resistance spot Welding, etc.) have been pushed to their technological limits and a further technological development is needed. The present research describes a new joining technology based on resistance Welding process for joining ultra-high strength steel 22MnB5 (AS150) with aluminum sheets AW 6016. The technology consists of a two-stage resistance spot Welding process with an additional simple cost-effective joining element. Its implementation allows joining aluminum and steel on extremely short flanges of 10 mm using short time Projection Welding with high-energy concentration. Joining elements—cylinders made of Cu- and Fe-based wires with diameter 1.6 mm and length 10 mm - were welded using the common resistance spot Welding equipment. Experimental results have shown that all tested materials for joining dissimilar steel-aluminum compounds can be successfully used and the weld current ranges are sufficient for industrial application.
Kuang-hung Tseng - One of the best experts on this subject based on the ideXlab platform.
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Small-scale Projection lap-joint Welding of KOVAR alloy and SPCC steel
Journal of The Chinese Institute of Engineers, 2012Co-Authors: Yung-chang Chen, Kuang-hung Tseng, Hsiang-cheng WangAbstract:The objective of this study was to investigate the effect of Projection heights and operating conditions on Projection collapse, nugget size, and joint strength of KOVAR alloy and steel plate cold-rolled commercial (SPCC) grade in small-scale Projection Welding of dissimilar metals. All welds were produced with a capacitor charging power supply. Three Projection designs with different heights were used. Harris and Riley-type Projection was embossed on the SPCC steel sheets. Nugget size was estimated using a peel test. Joint strength was evaluated using a tensile-shear test. The results indicated that a low-level Projection has a positive effect, increasing the load-bearing capacity of Projection. The nugget diameter and joint strength increase as the weld current and Projection height increase. Increasing the electrode force will produce a small nugget. Nugget size is a good indicator of the strength of the welded joint. This study also found that a cold-collapse ratio of approximately 25% produces the hi...
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Study on Nugget Diameter and Joint Strength of Dissimilar Metals in Capacitor Charging Projection Welding
Key Engineering Materials, 2011Co-Authors: Kuang-hung Tseng, Yung Chuan ChenAbstract:The purpose of this study was to investigate the effect of operating conditions on nugget diameter and joint strength of KOVAR alloy and SPCC steel in Projection Welding of dissimilar metals. All Projection welds were produced with a capacitor charging power supply. Harris and Riley type Projection was embossed on SPCC steel sheet. The nugget diameter was estimated using a peel test. The lap-joint strength of Projection welds was evaluated using a tensile-shear test. The results indicated that the nugget diameter and joint strength increase as the weld current increase. Increasing the electrode force will produce a small nugget diameter. The nugget diameter of Projection welds is a good indicator of the lap-joint strength.
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Process Parameters in Resistance Projection Welding for Optical Transmission Device Package
Journal of Materials Engineering and Performance, 2011Co-Authors: Her-yueh Huang, Kuang-hung TsengAbstract:The effects of main process parameters and electrode materials on joint quality (charging voltage and operating force) were investigated using detailed metallurgical examination and the helium leak test. The electrode materials used for resistance Projection Welding were brass and Cr-Cu alloy. The TO-Can components (cap and header) were nickel-coated SPCC steel. The results indicated that when the operating pressure increased, the electrode displacement increased, causing expulsion and distortion of the welds. The nugget area increased with the increase of charging voltage; however, it decreased with the increase of operating pressure. Results from the optical microscopy analysis showed that a larger acceptable Welding range was achieved by using Cr-Cu electrodes. TO-Can in the acceptable and expulsion range successfully passed the helium leak rate of less than 5 × 10^−8 mbar L/s. For commercial purposes, where dimensions have to be exact and without deformation, the TO-Can components produced in the expulsion zone cannot be used.
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Resistance Projection Welding for TO-Can style package
Acta Metallurgica Sinica (english Letters), 2009Co-Authors: Her-yueh Huang, Kuang-hung TsengAbstract:The effects of the process parameters on the joint quality of TO-Can using resistance Projection Welding were investigated. A capacitor discharge stored energy Welding machine was used for joining caps and headers both coated with nickel SPCC steel. The electrode materials used in this study were brass and W- Cu alloy. Experimental results indicated that the peak current of the W-Cu electrode was higher than that of the brass electrode, irrespective of the operating pressure variation. Increased operating pressure influenced the interfacial heat generation and nugget formation. The nugget area increased rapidly with increasing charging voltage, resulting in expulsions and electrodes getting stuck. An acceptable Welding zone was found in the relationship between the charging voltage and the operating pressure. Representative test specimens of the acceptable Welding zone satisfactorily passed the helium leak test. The microscopic morphology of the nugget showed a recrystallized fine grain structure resulting in the nugget being harder than with the HAZ.
