Pub Date : 2024-12-25DOI: 10.1016/j.jajp.2024.100275
Shoeib Karami , Mohammad Yousefieh , Homam Naffakh-Moosavy
In this study, the key findings of evaluating laser beam welding parameters on the multi-layered structure of 6061 aluminum alloys fabricating by accumulative roll bonding process are reported, considering fostering mechanical properties concerning the influence of filler metal and welding speed on the weld bead quality by taking into account reducing welding defects. Welding defects, including porosity and hot cracks, formed due to the evaporation of low-molten elements such as Mg, which can be reduced by adding filler metal to compensate for the vaporized Mg content. The optimal tensile strength is related to the laser beam welding using filler metal at the speed of 40 mm/s. Work-hardening behavior leading to fatigue life improvement is associated with the rearrangement and multiplication of dislocations in all samples. The related mechanisms responsible for the microstructural evolution during the cyclic deformation process were described by transmission electron microscopy observation. The fracture surface analyzed by scanning electron microscopy indicated that delamination contributing to local necking is the leading cause of fracture in accumulative roll-bonded 6061 aluminum alloy. However, the fracture morphology of laser-welded samples displays a heterogeneous distribution of equiaxed dimples along with negligible serpentine sliding, indicating a ductile fracture mode.
{"title":"The effect of laser welding parameters on mechanical properties and microstructure evolution of multi-layered 6061 aluminum alloy","authors":"Shoeib Karami , Mohammad Yousefieh , Homam Naffakh-Moosavy","doi":"10.1016/j.jajp.2024.100275","DOIUrl":"10.1016/j.jajp.2024.100275","url":null,"abstract":"<div><div>In this study, the key findings of evaluating laser beam welding parameters on the multi-layered structure of 6061 aluminum alloys fabricating by accumulative roll bonding process are reported, considering fostering mechanical properties concerning the influence of filler metal and welding speed on the weld bead quality by taking into account reducing welding defects. Welding defects, including porosity and hot cracks, formed due to the evaporation of low-molten elements such as Mg, which can be reduced by adding filler metal to compensate for the vaporized Mg content. The optimal tensile strength is related to the laser beam welding using filler metal at the speed of 40 mm/s. Work-hardening behavior leading to fatigue life improvement is associated with the rearrangement and multiplication of dislocations in all samples. The related mechanisms responsible for the microstructural evolution during the cyclic deformation process were described by transmission electron microscopy observation. The fracture surface analyzed by scanning electron microscopy indicated that delamination contributing to local necking is the leading cause of fracture in accumulative roll-bonded 6061 aluminum alloy. However, the fracture morphology of laser-welded samples displays a heterogeneous distribution of equiaxed dimples along with negligible serpentine sliding, indicating a ductile fracture mode.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"11 ","pages":"Article 100275"},"PeriodicalIF":3.8,"publicationDate":"2024-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143133038","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}
Hollow aluminum panels are designed to be both rigid and lightweight, making them ideal for structural applications where material efficiency is critical. However, reliable welding techniques are essential to join these panels effectively. A common challenge during welding is the formation of porosity defects, caused by the varying solubility of hydrogen gas as aluminum transitions between liquid and solid states. While solid-state welding methods like Friction Stir Welding (FSW) are effective in minimizing porosity, they present difficulties when applied to thick materials such as extrusion panels. Thick structures often require multiple welding passes, resulting in increased production time and higher costs. To address these challenges, this study investigates the potential of an innovative one-step double-acting FSW technique. This novel method uses two tools operating simultaneously, providing dual sources of frictional heat and compressive force, a concept unexplored in traditional FSW methods. The research focuses on the influence of shoulder diameter—a critical parameter—on the physical and mechanical properties of AA6061 hollow aluminum panels. Experiments were conducted using shoulder diameters of 20, 22, and 24 mm, with process parameters set at a transverse speed of 30 mm/min, a rotational speed of 1500 rpm, and a tilt angle of 2°. The findings demonstrate that increasing the shoulder diameter significantly enhances the mechanical performance of the welded joints. The specimen welded with a 24 mm shoulder diameter achieved the best results, with a hardness value of 71.73 HVN, a load capacity of 15.51 kN, and a bending strength of 4.7 MPa. These results underline the effectiveness of the one-step double-acting FSW technique in improving the quality and efficiency of welding hollow aluminum panels, offering a practical solution to the limitations of conventional FSW in thick-structured materials.
{"title":"Effect of tool diameter on the joint properties of AA6061 hollow panels using a novel one-step double-acting Friction Stir Weld method","authors":"Nurul Muhayat, Rani Dwi Larasati, Ericha D.W.S. Putri, Eko Prasetya Budiana, Triyono","doi":"10.1016/j.jajp.2024.100277","DOIUrl":"10.1016/j.jajp.2024.100277","url":null,"abstract":"<div><div>Hollow aluminum panels are designed to be both rigid and lightweight, making them ideal for structural applications where material efficiency is critical. However, reliable welding techniques are essential to join these panels effectively. A common challenge during welding is the formation of porosity defects, caused by the varying solubility of hydrogen gas as aluminum transitions between liquid and solid states. While solid-state welding methods like Friction Stir Welding (FSW) are effective in minimizing porosity, they present difficulties when applied to thick materials such as extrusion panels. Thick structures often require multiple welding passes, resulting in increased production time and higher costs. To address these challenges, this study investigates the potential of an innovative one-step double-acting FSW technique. This novel method uses two tools operating simultaneously, providing dual sources of frictional heat and compressive force, a concept unexplored in traditional FSW methods. The research focuses on the influence of shoulder diameter—a critical parameter—on the physical and mechanical properties of AA6061 hollow aluminum panels. Experiments were conducted using shoulder diameters of 20, 22, and 24 mm, with process parameters set at a transverse speed of 30 mm/min, a rotational speed of 1500 rpm, and a tilt angle of 2°. The findings demonstrate that increasing the shoulder diameter significantly enhances the mechanical performance of the welded joints. The specimen welded with a 24 mm shoulder diameter achieved the best results, with a hardness value of 71.73 HVN, a load capacity of 15.51 kN, and a bending strength of 4.7 MPa. These results underline the effectiveness of the one-step double-acting FSW technique in improving the quality and efficiency of welding hollow aluminum panels, offering a practical solution to the limitations of conventional FSW in thick-structured materials.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"11 ","pages":"Article 100277"},"PeriodicalIF":3.8,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143133026","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}
Pub Date : 2024-12-18DOI: 10.1016/j.jajp.2024.100274
Petr Slepička , Klaudia Hurtuková , Silvie Rimpelová , Šárka Trhoňová , Jiří Martan , Michal Procházka , Václav Švorčík , Nikola Slepičková Kasálková
In this study, we investigated the effects of carbon layer deposition on titanium (Ti) and titanium alloy (TiAlV) substrates using "flash" vaporization and pulsed laser deposition (PLD) techniques. Raman spectroscopy revealed that the PLD method produced a higher sp3 carbon bond content than the evaporation method (61 vs. 47 %). Atomic force microscopy and surface wettability analyzes showed differences in surface roughness and contact angle, with PLD-deposited samples exhibiting enhanced hydrophilicity and wrinkled morphology. Subsequent laser annealing optimized surface properties by increasing hydrophobicity, which is critical for cell adhesion. Surface chemistry analysis via scanning electron microscopy and energy dispersive spectroscopy demonstrated significant carbon enrichment in the PLD-deposited samples, mainly for TiAlV substrate. Cytocompatibility tests using human osteosarcoma cells (U-2 OS) revealed varying cell adhesion and proliferation based on surface modification, with PLD-deposited layers promoting better cell interaction. Both carbon deposition techniques enhanced antibacterial effect. This suggests the potential of PLD-deposited carbon layers for biomedical applications, particularly in enhancing implant surfaces for improved cell growth and adhesion, and reduce bacteria, the nanostructured substrates may serve also for subsequent replication process into polymer.
{"title":"Ti and TiAlV foils enhanced with PLD and flash-deposited carbon: On cytocompatibility and antibacterial activity","authors":"Petr Slepička , Klaudia Hurtuková , Silvie Rimpelová , Šárka Trhoňová , Jiří Martan , Michal Procházka , Václav Švorčík , Nikola Slepičková Kasálková","doi":"10.1016/j.jajp.2024.100274","DOIUrl":"10.1016/j.jajp.2024.100274","url":null,"abstract":"<div><div>In this study, we investigated the effects of carbon layer deposition on titanium (Ti) and titanium alloy (TiAlV) substrates using \"flash\" vaporization and pulsed laser deposition (PLD) techniques. Raman spectroscopy revealed that the PLD method produced a higher sp3 carbon bond content than the evaporation method (61 vs<em>.</em> 47 %). Atomic force microscopy and surface wettability analyzes showed differences in surface roughness and contact angle, with PLD-deposited samples exhibiting enhanced hydrophilicity and wrinkled morphology. Subsequent laser annealing optimized surface properties by increasing hydrophobicity, which is critical for cell adhesion. Surface chemistry analysis via scanning electron microscopy and energy dispersive spectroscopy demonstrated significant carbon enrichment in the PLD-deposited samples, mainly for TiAlV substrate. Cytocompatibility tests using human osteosarcoma cells (U-2 OS) revealed varying cell adhesion and proliferation based on surface modification, with PLD-deposited layers promoting better cell interaction. Both carbon deposition techniques enhanced antibacterial effect. This suggests the potential of PLD-deposited carbon layers for biomedical applications, particularly in enhancing implant surfaces for improved cell growth and adhesion, and reduce bacteria, the nanostructured substrates may serve also for subsequent replication process into polymer.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"11 ","pages":"Article 100274"},"PeriodicalIF":3.8,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143133082","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}
Pub Date : 2024-12-18DOI: 10.1016/j.jajp.2024.100276
Angshuman Kapil , Anupam Vivek , Glenn Daehn
This study investigates the influence of Zinc (Zn) coating on the mechanical properties of impact spot welded joints between Aluminum (Al) 6111 alloy and galvanized high-strength low-alloy (HSLA) 340 steel using vaporizing foil actuator welding (VFAW). The Zn coating significantly impacts the weld interface, leading to a heterogeneous structure with regions of retained Zn and trapped jetted material. These regions inhibit direct contact between Al and steel, preventing effective metallurgical bonding and reducing joint strength by 60 % compared to uncoated steel. While the Zn coating impedes bond formation in some areas, near-complete Zn removal in other zones promotes localized ductile tearing and partial bonding, slightly mitigating the overall negative effect. Additionally, a brazing effect outside the weld zone, resulting from the jetting and solidification of Zn and Al-Zn, provides some strength to the joint. The findings highlight the complex role of Zn coating in VFAW, demonstrating that a continuous Zn layer at the weld interface is more detrimental to joint performance than discrete and thin intermetallic compounds.
{"title":"Role of zinc coating on joint properties in impact spot welded Al 6111 aluminum alloy to galvanized high-strength low-alloy steel","authors":"Angshuman Kapil , Anupam Vivek , Glenn Daehn","doi":"10.1016/j.jajp.2024.100276","DOIUrl":"10.1016/j.jajp.2024.100276","url":null,"abstract":"<div><div>This study investigates the influence of Zinc (Zn) coating on the mechanical properties of impact spot welded joints between Aluminum (Al) 6111 alloy and galvanized high-strength low-alloy (HSLA) 340 steel using vaporizing foil actuator welding (VFAW). The Zn coating significantly impacts the weld interface, leading to a heterogeneous structure with regions of retained Zn and trapped jetted material. These regions inhibit direct contact between Al and steel, preventing effective metallurgical bonding and reducing joint strength by 60 % compared to uncoated steel. While the Zn coating impedes bond formation in some areas, near-complete Zn removal in other zones promotes localized ductile tearing and partial bonding, slightly mitigating the overall negative effect. Additionally, a brazing effect outside the weld zone, resulting from the jetting and solidification of Zn and Al-Zn, provides some strength to the joint. The findings highlight the complex role of Zn coating in VFAW, demonstrating that a continuous Zn layer at the weld interface is more detrimental to joint performance than discrete and thin intermetallic compounds.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"11 ","pages":"Article 100276"},"PeriodicalIF":3.8,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143133084","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}
Degradation is a common phenomenon in gas turbine components. Among additive manufacturing (AM) methods like direct laser deposition (DLD) and laser powder bed fusion (LPBF), DLD has been widely studied due to its ease in repair processes. However, LPBF offers higher dimensional accuracy, better surface quality, and reduced stress. This study employed LPBF of IN625 on an IN738 substrate for repair purposes. A wide range of process parameters (power at 100, 150, and 200 W and scan speeds between 100 mm/s to 2700 mm/s) was evaluated. The reasons behind process parameters' influence on defect formation, such as pores and cracks, were investigated, as these aspects have been less emphasized in prior studies. The relationship between process parameters, melt pool shape, pore formation, and changes in elemental concentration was explored. It was found that concentration peaks at the interface are the main factor in crack formation, enabling predictions of cracking behavior. Elements diffuse from rich to poor regions at the IN625/IN738 interface. At scan speeds ≤ 500 mm/s, increasing speed and power both increase elemental concentration at the interface, but speed promotes elemental accumulation behind the interface, while power enhances homogenization. The effect of process parameters on microhardness and cell size was also examined. It was determined that cracks do not form in softer nickel-based matrices where microhardness remains below the critical threshold of 256 HV.
{"title":"A new approach to the reasons for dependency of defects formation to the process parameters in laser powder bed fusion of IN625 on the IN738LC substrate","authors":"Amirhossein Riazi , Seyed Hossein Razavi , Alireza Khavandi , Mostafa Amirjan , Mohsen Ostad Shabani , Hossein Davarzani","doi":"10.1016/j.jajp.2024.100273","DOIUrl":"10.1016/j.jajp.2024.100273","url":null,"abstract":"<div><div>Degradation is a common phenomenon in gas turbine components. Among additive manufacturing (AM) methods like direct laser deposition (DLD) and laser powder bed fusion (LPBF), DLD has been widely studied due to its ease in repair processes. However, LPBF offers higher dimensional accuracy, better surface quality, and reduced stress. This study employed LPBF of IN625 on an IN738 substrate for repair purposes. A wide range of process parameters (power at 100, 150, and 200 W and scan speeds between 100 mm/s to 2700 mm/s) was evaluated. The reasons behind process parameters' influence on defect formation, such as pores and cracks, were investigated, as these aspects have been less emphasized in prior studies. The relationship between process parameters, melt pool shape, pore formation, and changes in elemental concentration was explored. It was found that concentration peaks at the interface are the main factor in crack formation, enabling predictions of cracking behavior. Elements diffuse from rich to poor regions at the IN625/IN738 interface. At scan speeds ≤ 500 mm/s, increasing speed and power both increase elemental concentration at the interface, but speed promotes elemental accumulation behind the interface, while power enhances homogenization. The effect of process parameters on microhardness and cell size was also examined. It was determined that cracks do not form in softer nickel-based matrices where microhardness remains below the critical threshold of 256 HV.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"11 ","pages":"Article 100273"},"PeriodicalIF":3.8,"publicationDate":"2024-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143133037","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}
Linear friction welding (LFW) is a well-established solid-state joining technique. However, its application in T-joint configurations remains unexplored. This study investigated the effects of welding parameters, such as oscillation direction, upset, and applied pressure after oscillation, on linear friction welded (LFWed) T-joints using low-carbon steel SM490A. The flash ejection behavior, flash profiles, microhardness, microstructure at the welding interface, and tensile properties of the joints were evaluated under various welding conditions. The results indicated that flash symmetry was lower along the oscillation direction and higher perpendicular to it. Short-side oscillation produced more homogeneous flash ejection compared to long-side oscillation. No distinct softening zones were observed in the hardness profiles of the LFWed T-joints. The microstructure at the welding interface consisted of martensite, bainite, and ferrite, indicating that the weld region reached temperatures above the A1 temperature. The martensite fraction and hardness increased with higher upset and applied pressure after oscillation. Tensile tests revealed 100 % joint efficiency across all welding conditions, with ductile fracture occurring in the base metal due to the absence of welding defects and increased hardness at the interface.
线性摩擦焊(LFW)是一种成熟的固态连接技术。然而,它在 T 型接头结构中的应用仍有待探索。本研究使用低碳钢 SM490A 研究了焊接参数对线性摩擦焊接(LFWed)T 型接头的影响,如摆动方向、镦粗和摆动后施加的压力。在不同的焊接条件下,对接头的飞溅行为、飞溅轮廓、显微硬度、焊接界面的显微组织和拉伸性能进行了评估。结果表明,沿振荡方向的闪光对称性较低,而垂直于振荡方向的闪光对称性较高。与长边振荡相比,短边振荡产生的闪光喷射更均匀。在低频焊接 T 型接头的硬度曲线上没有观察到明显的软化区。焊接界面的微观结构由马氏体、贝氏体和铁素体组成,表明焊接区域的温度高于 A1 温度。马氏体的比例和硬度随着振荡后更大的扰动和施加压力而增加。拉伸试验表明,在所有焊接条件下,接头效率都达到了 100%,由于没有焊接缺陷和界面硬度增加,母材发生了韧性断裂。
{"title":"Linear friction welding of T-Joints in low carbon steel: Effect of welding parameters on joint quality","authors":"Huilin Miao , Takayuki Yamashita , Kohsaku Ushioda , Seiichiro Tsutsumi , Yoshiaki Morisada , Hidetoshi Fujii","doi":"10.1016/j.jajp.2024.100267","DOIUrl":"10.1016/j.jajp.2024.100267","url":null,"abstract":"<div><div>Linear friction welding (LFW) is a well-established solid-state joining technique. However, its application in T-joint configurations remains unexplored. This study investigated the effects of welding parameters, such as oscillation direction, upset, and applied pressure after oscillation, on linear friction welded (LFWed) T-joints using low-carbon steel SM490A. The flash ejection behavior, flash profiles, microhardness, microstructure at the welding interface, and tensile properties of the joints were evaluated under various welding conditions. The results indicated that flash symmetry was lower along the oscillation direction and higher perpendicular to it. Short-side oscillation produced more homogeneous flash ejection compared to long-side oscillation. No distinct softening zones were observed in the hardness profiles of the LFWed T-joints. The microstructure at the welding interface consisted of martensite, bainite, and ferrite, indicating that the weld region reached temperatures above the <em>A<sub>1</sub></em> temperature. The martensite fraction and hardness increased with higher upset and applied pressure after oscillation. Tensile tests revealed 100 % joint efficiency across all welding conditions, with ductile fracture occurring in the base metal due to the absence of welding defects and increased hardness at the interface.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"10 ","pages":"Article 100267"},"PeriodicalIF":3.8,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142593524","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}
Pub Date : 2024-11-01DOI: 10.1016/j.jajp.2024.100265
Pedro M.S. Rosado , Rui F.V. Sampaio , João P.M. Pragana , Ivo M.F. Bragança , Carlos M.A. Silva , Paulo A.F. Martins
This paper presents a novel manufacturing process for producing innovative bi-material collector coins with free-rotating inner elements. The inner elements are fabricated using additive manufacturing, enabling the creation of coins with complex and intricate geometric details that would be unattainable using conventional wrought materials. The outer elements (rings) are metallic, and this study addresses the challenge of securely connecting them to the inner elements through force-closed mechanisms formed during the coin minting process. Finite element modeling, combined with experimentation on bi-material (polymer-metal and metal-metal) coins, is employed to analyze material flow, assess minting forces, and evaluate contact pressures at the force-closed joints. The analysis ensures that adequate destructive forces are required to separate the inner elements from the rings and provides insights into selecting the appropriate process parameters for simultaneous coining and joining. The successful production of the first bi-material collector coin prototypes with free-rotational inner elements validates the overall development.
{"title":"Joining by forming of bi-material collector coins with rotating elements","authors":"Pedro M.S. Rosado , Rui F.V. Sampaio , João P.M. Pragana , Ivo M.F. Bragança , Carlos M.A. Silva , Paulo A.F. Martins","doi":"10.1016/j.jajp.2024.100265","DOIUrl":"10.1016/j.jajp.2024.100265","url":null,"abstract":"<div><div>This paper presents a novel manufacturing process for producing innovative bi-material collector coins with free-rotating inner elements. The inner elements are fabricated using additive manufacturing, enabling the creation of coins with complex and intricate geometric details that would be unattainable using conventional wrought materials. The outer elements (rings) are metallic, and this study addresses the challenge of securely connecting them to the inner elements through force-closed mechanisms formed during the coin minting process. Finite element modeling, combined with experimentation on bi-material (polymer-metal and metal-metal) coins, is employed to analyze material flow, assess minting forces, and evaluate contact pressures at the force-closed joints. The analysis ensures that adequate destructive forces are required to separate the inner elements from the rings and provides insights into selecting the appropriate process parameters for simultaneous coining and joining. The successful production of the first bi-material collector coin prototypes with free-rotational inner elements validates the overall development.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"10 ","pages":"Article 100265"},"PeriodicalIF":3.8,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142572110","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}
Pub Date : 2024-11-01DOI: 10.1016/j.jajp.2024.100263
Christian Steinfelder, Dennis Rempel, Alexander Brosius
This study focuses on the phenomenological change in material strength caused by a specific heat treatment and the subsequent analysis of the influence on the clinching process and the resulting joint properties. For this purpose, three series of tests were performed. In the first series of tests, the influence of heat treatment up to 340 °C on the mechanical properties of an age-hardenable AlMgSi alloy was investigated. Holding time and temperature were varied and the material strength was evaluated by tensile and hardness tests. Two strength-increasing and two strength-reducing heat treatment parameters were identified. In the second series of tests, selected heat treatment parameters were applied to a larger number of specimens and the joint strength was investigated by shear and head tensile tests. In the shear tensile test, mainly the properties of the punch-side material have an influence on the resulting joint strength. A change in strength of the die-side material can be neglected. In contrast, the properties of both sheets are important in the head tensile test. The strength of the joint will only increase if the strength of both sheets is increased. In general, a strength increasing heat treatment resulted in higher joint strength. In the third series of tests, the factor of punch displacement was considered, which was demonstrated to directly influence the formation of the clinched joint geometry.
本研究的重点是特定热处理对材料强度造成的现象变化,以及随后对夹紧过程和由此产生的接头性能的影响分析。为此,我们进行了三个系列的测试。在第一个系列试验中,研究了最高温度为 340 °C 的热处理对时效硬化铝镁硅合金机械性能的影响。改变了保温时间和温度,并通过拉伸和硬度测试评估了材料强度。确定了两个提高强度和两个降低强度的热处理参数。在第二系列试验中,对更多试样采用了选定的热处理参数,并通过剪切和头部拉伸试验研究了接头强度。在剪切拉伸试验中,主要是冲头侧材料的特性对接头强度产生影响。模具侧材料强度的变化可以忽略不计。相反,在封头拉伸试验中,两张板材的特性都很重要。只有同时提高两片板材的强度,接头的强度才会提高。一般来说,增加强度的热处理可提高接头强度。在第三系列试验中,考虑了冲头位移的因素,结果表明冲头位移直接影响咬合接头几何形状的形成。
{"title":"Influence of the material properties on the clinching process and the resulting load-bearing capacity of the joint","authors":"Christian Steinfelder, Dennis Rempel, Alexander Brosius","doi":"10.1016/j.jajp.2024.100263","DOIUrl":"10.1016/j.jajp.2024.100263","url":null,"abstract":"<div><div>This study focuses on the phenomenological change in material strength caused by a specific heat treatment and the subsequent analysis of the influence on the clinching process and the resulting joint properties. For this purpose, three series of tests were performed. In the first series of tests, the influence of heat treatment up to 340 °C on the mechanical properties of an age-hardenable AlMgSi alloy was investigated. Holding time and temperature were varied and the material strength was evaluated by tensile and hardness tests. Two strength-increasing and two strength-reducing heat treatment parameters were identified. In the second series of tests, selected heat treatment parameters were applied to a larger number of specimens and the joint strength was investigated by shear and head tensile tests. In the shear tensile test, mainly the properties of the punch-side material have an influence on the resulting joint strength. A change in strength of the die-side material can be neglected. In contrast, the properties of both sheets are important in the head tensile test. The strength of the joint will only increase if the strength of both sheets is increased. In general, a strength increasing heat treatment resulted in higher joint strength. In the third series of tests, the factor of punch displacement was considered, which was demonstrated to directly influence the formation of the clinched joint geometry.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"10 ","pages":"Article 100263"},"PeriodicalIF":3.8,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552098","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}
Pub Date : 2024-11-01DOI: 10.1016/j.jajp.2024.100261
Andreas Andersson Lassila, Tobias Andersson, Rohollah Ghasemi, Dan Lönn
In the battery pack assembly, it is essential to ensure that the cell-to-busbar joints can be produced with high quality and with minimal impact on the individual battery cells. This study examines the influence of process parameters on the joint quality for nickel-plated copper and steel plates, laser welded in an overlap configuration. Artificial neural network-based meta models, trained on numerical results from computational fluid dynamics simulations of the laser welding process, are used to predict and evaluate the joint quality. A set of optimized process parameters is identified, in order to simultaneously maximize the interface width for the joints, and minimize the formation of undercuts and in-process temperatures. In an meta model-based multi-objective optimization approach, the non-dominated sorting genetic algorithm II (NSGA-II) is used to efficiently search for trade-off solutions and the meta models are used for objective approximation. As a result, the objective evaluation time is decreased from around 9 h, when evaluated directly from numerical simulations, to only tenths of a second. From the Pareto-optimal front of trade-off solutions, three optimal solutions are selected for validation. The selected solutions are validated through laser welding experiments and numerical simulations, resulting in joints with large interface widths and low in-process temperatures without a full penetration.
在电池组组装过程中,必须确保电池单元与母线的连接质量高,并且对单个电池单元的影响最小。本研究探讨了工艺参数对重叠配置激光焊接镀镍铜板和钢板接头质量的影响。基于人工神经网络的元模型是在激光焊接过程的计算流体动力学模拟数值结果的基础上训练而成的,用于预测和评估接头质量。确定了一组优化的工艺参数,以便同时最大限度地增加接头的界面宽度,并最大限度地减少缺口的形成和降低加工过程中的温度。在基于元模型的多目标优化方法中,非支配排序遗传算法 II (NSGA-II) 被用来高效地搜索折衷解决方案,元模型被用来进行目标近似。因此,目标评估时间从直接从数值模拟评估的约 9 小时缩短到仅十分之一秒。从权衡解决方案的帕累托最优前沿中,选出三个最优解决方案进行验证。所选方案通过激光焊接实验和数值模拟进行了验证,结果是接头界面宽度大,加工过程温度低,且没有完全熔透。
{"title":"Enhancement of joint quality for laser welded dissimilar material cell-to-busbar joints using meta model-based multi-objective optimization","authors":"Andreas Andersson Lassila, Tobias Andersson, Rohollah Ghasemi, Dan Lönn","doi":"10.1016/j.jajp.2024.100261","DOIUrl":"10.1016/j.jajp.2024.100261","url":null,"abstract":"<div><div>In the battery pack assembly, it is essential to ensure that the cell-to-busbar joints can be produced with high quality and with minimal impact on the individual battery cells. This study examines the influence of process parameters on the joint quality for nickel-plated copper and steel plates, laser welded in an overlap configuration. Artificial neural network-based meta models, trained on numerical results from computational fluid dynamics simulations of the laser welding process, are used to predict and evaluate the joint quality. A set of optimized process parameters is identified, in order to simultaneously maximize the interface width for the joints, and minimize the formation of undercuts and in-process temperatures. In an meta model-based multi-objective optimization approach, the non-dominated sorting genetic algorithm II (NSGA-II) is used to efficiently search for trade-off solutions and the meta models are used for objective approximation. As a result, the objective evaluation time is decreased from around 9 h, when evaluated directly from numerical simulations, to only tenths of a second. From the Pareto-optimal front of trade-off solutions, three optimal solutions are selected for validation. The selected solutions are validated through laser welding experiments and numerical simulations, resulting in joints with large interface widths and low in-process temperatures without a full penetration.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"10 ","pages":"Article 100261"},"PeriodicalIF":3.8,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552099","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}
Pub Date : 2024-11-01DOI: 10.1016/j.jajp.2024.100271
Julian Popp, Dietmar Drummer
This study focuses on the integration of continuous fiber-reinforced thermoplastics (CFRT) with metal components through the use of cold-formed pin structures. Comparing six different joining methods with varying heat generation approaches, we investigated their impact on the mechanical properties and joint integrity. Ultrasonic vibration emerged as a highly promising method, offering both rapid joining operations and favorable mechanical characteristics with average failure loads in lap shear tests of up to 249 N. In comparison, vibration welding showed drawbacks, resulting in CFRT damage, potential pin failure, and diminished mechanical performance with maximum average lap shear loads of 216 N. Additionally, traces of zinc residue were identified on the CFRT surface, raising concerns about the corrosion resistance of the metal component. In summary, vibration welding appears unsuitable for pin joining applications. Infrared heating, while showcasing good mechanical performance with lap shear loads of up to 257 N, proved to be a more time-consuming process compared to ultrasonic joining. It also resulted in inferior mechanical strength under shear load in the direction of the fiber orientation (238 N). To assess the mechanical potential of pin joints relatively to established joining methods, we created and tested adhesively joined reference samples. Pin joints demonstrated a significant advantage under shear load, showing approximately double the shear strength (17.8 MPa) compared to adhesively joined samples (8.9 MPa). However, under normal load, pin joints exhibited lower strength, highlighting the need for further optimization to enhance their practical applicability.
{"title":"Investigation of different process routes for joining thermoplastic composite/steel joints via the embedding of cold formed metallic pin structures","authors":"Julian Popp, Dietmar Drummer","doi":"10.1016/j.jajp.2024.100271","DOIUrl":"10.1016/j.jajp.2024.100271","url":null,"abstract":"<div><div>This study focuses on the integration of continuous fiber-reinforced thermoplastics (CFRT) with metal components through the use of cold-formed pin structures. Comparing six different joining methods with varying heat generation approaches, we investigated their impact on the mechanical properties and joint integrity. Ultrasonic vibration emerged as a highly promising method, offering both rapid joining operations and favorable mechanical characteristics with average failure loads in lap shear tests of up to 249 N. In comparison, vibration welding showed drawbacks, resulting in CFRT damage, potential pin failure, and diminished mechanical performance with maximum average lap shear loads of 216 N. Additionally, traces of zinc residue were identified on the CFRT surface, raising concerns about the corrosion resistance of the metal component. In summary, vibration welding appears unsuitable for pin joining applications. Infrared heating, while showcasing good mechanical performance with lap shear loads of up to 257 N, proved to be a more time-consuming process compared to ultrasonic joining. It also resulted in inferior mechanical strength under shear load in the direction of the fiber orientation (238 N). To assess the mechanical potential of pin joints relatively to established joining methods, we created and tested adhesively joined reference samples. Pin joints demonstrated a significant advantage under shear load, showing approximately double the shear strength (17.8 MPa) compared to adhesively joined samples (8.9 MPa). However, under normal load, pin joints exhibited lower strength, highlighting the need for further optimization to enhance their practical applicability.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"10 ","pages":"Article 100271"},"PeriodicalIF":3.8,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143101728","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}