Pub Date : 2025-05-09DOI: 10.1016/j.jajp.2025.100310
Benjámin Márk Körömi , Zoltán Weltsch , Miklós Berczeli
Bonding technologies have evolved significantly over the past decades, playing a crucial role in the field of joining technologies. To date, however, there is no consensus among research groups as to whether surface texture or surface wettability, or both, affect the strength of bonded joints. Bonded joints, as a bonding technique, are highly dependent on the chemical composition of the adhesive or binder. It is also important to note that the strength and the quality of a bonded joint is greatly influenced by surface adhesion and its related phenomena. From a materials science perspective, surface adhesion is characterised by the level of surface wetting and the total surface energy. In addition, microtopographies and other geometrical features play a key role in bond formation. In this research, the goal is to create controlled microtopographies on DP600 steel surfaces, mainly using femtosecond pulsed laser surface treatment techniques. The ability of adhesives to fill microtopographies specifically, the extent and manner in which micro-scale geometries and structures are filled is also investigated. This allows for the establishment of correlations between the strength of adhesive bonds and the shape characteristics of the microtopography, both in the surface-activated and non-surface-activated states.
{"title":"Relationship between the developed interfacial area ratio and the adhesion of the bonded joint","authors":"Benjámin Márk Körömi , Zoltán Weltsch , Miklós Berczeli","doi":"10.1016/j.jajp.2025.100310","DOIUrl":"10.1016/j.jajp.2025.100310","url":null,"abstract":"<div><div>Bonding technologies have evolved significantly over the past decades, playing a crucial role in the field of joining technologies. To date, however, there is no consensus among research groups as to whether surface texture or surface wettability, or both, affect the strength of bonded joints. Bonded joints, as a bonding technique, are highly dependent on the chemical composition of the adhesive or binder. It is also important to note that the strength and the quality of a bonded joint is greatly influenced by surface adhesion and its related phenomena. From a materials science perspective, surface adhesion is characterised by the level of surface wetting and the total surface energy. In addition, microtopographies and other geometrical features play a key role in bond formation. In this research, the goal is to create controlled microtopographies on DP600 steel surfaces, mainly using femtosecond pulsed laser surface treatment techniques. The ability of adhesives to fill microtopographies specifically, the extent and manner in which micro-scale geometries and structures are filled is also investigated. This allows for the establishment of correlations between the strength of adhesive bonds and the shape characteristics of the microtopography, both in the surface-activated and non-surface-activated states.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"11 ","pages":"Article 100310"},"PeriodicalIF":3.8,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143941190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study investigated the effects of pre-deformation induced by asymmetric rolling on copper-based metal, as well as rotational speed during friction stir processing, on the microstructure, mechanical properties, and electrical conductivity of tungsten-reinforced copper matrix composites. The results show that increasing the rotational speed up to 800 rpm leads to a more uniform distribution of tungsten particles within the stir zone. However, at rotational speeds above 800 rpm, the distribution of tungsten reinforcing particles becomes less uniform. The accumulated strain in the stir zone increases from 0.3056 to 0.3967 s-1 as the rotational speed rises from 600 to 1200 rpm. Additionally, as the tool rotational speed increases from 600 to 1200 rpm, the grain size in the stir zone grows from 6.2 ± 0.7 to 13.2 ± 1.5 µm. The Cu-W composite processed at a tool rotational speed of 800 rpm achieves the highest values in hardness (124.9 ± 8.9 HV0.1), ultimate tensile strength (307.4 ± 11.8 MPa), tensile toughness (92.1 ± 1.1 MJ/m3), and electrical conductivity (92.8 ± 1.3 %IACS). Compared to the as-rolled copper-based metal, the electrical conductivity of the Cu-W composite fabricated at 800 rpm increases by 8.8 %.
{"title":"Optimizing microstructure and performance: The impact of pre-deformation and rotational speed on friction stir processed Cu-W composites","authors":"Masoomeh Oliaei, Roohollah Jamaati, Hamed Jamshidi Aval","doi":"10.1016/j.jajp.2025.100308","DOIUrl":"10.1016/j.jajp.2025.100308","url":null,"abstract":"<div><div>This study investigated the effects of pre-deformation induced by asymmetric rolling on copper-based metal, as well as rotational speed during friction stir processing, on the microstructure, mechanical properties, and electrical conductivity of tungsten-reinforced copper matrix composites. The results show that increasing the rotational speed up to 800 rpm leads to a more uniform distribution of tungsten particles within the stir zone. However, at rotational speeds above 800 rpm, the distribution of tungsten reinforcing particles becomes less uniform. The accumulated strain in the stir zone increases from 0.3056 to 0.3967 s<sup>-1</sup> as the rotational speed rises from 600 to 1200 rpm. Additionally, as the tool rotational speed increases from 600 to 1200 rpm, the grain size in the stir zone grows from 6.2 ± 0.7 to 13.2 ± 1.5 µm. The Cu-W composite processed at a tool rotational speed of 800 rpm achieves the highest values in hardness (124.9 ± 8.9 HV0.1), ultimate tensile strength (307.4 ± 11.8 MPa), tensile toughness (92.1 ± 1.1 MJ/m<sup>3</sup>), and electrical conductivity (92.8 ± 1.3 %IACS). Compared to the as-rolled copper-based metal, the electrical conductivity of the Cu-W composite fabricated at 800 rpm increases by 8.8 %.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"11 ","pages":"Article 100308"},"PeriodicalIF":3.8,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143921668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A layered composite of AA1050-AA5052 alloys was fabricated through roll bonding, and accumulative roll bonding (ARB) and subsequently subjected to friction stir processing (FSP). In this process, the annealed AA5052 and AA1050 sheets are used as raw materials. At first, preheating at 200 °C for 6 min preceded the rolling process in an induction furnace, achieving a 67 % reduction in the cross-sectional area. Then, two ARB stages were conducted. At the flow, the FSP process was conducted at constant transversal speeds of 750 rpm and 1180 rpm. Microstructural details were analyzed using optical microscopy (OM), scanning electron microscopy (SEM), and electron backscatter diffraction (EBSD). Mechanical properties were assessed through tensile test, microhardness measurement, and wear test. The results showed that recrystallization occurred due to FSP applied to the rolled sheet. The tensile strength after ARB and FSP was measured as 270 and 150 MPa, respectively. These values show an increase of 3.3 times and 1.8 times, respectively, compared to annealed AA1050. The maximum elongation after ARB and FSP was measured at about 9 and 30 %. Work hardening and grain refinement, respectively, had a significant role in increasing the elongation of the AA1050/AA5052 composites created by ARB and FSP. Furthermore, FSP enhanced the wear resistance of the AA1050-AA5052 composite created with two ARB steps by 70 %.
{"title":"Friction stir processing of AA1050/AA5052 composite produced by accumulative roll bonding process: Microstructure and mechanical properties","authors":"Hamid Partoyar , Hamid Reza Jafarian , Hamed Roghani , Ahad Mohammadzadeh , Akbar Heidarzadeh","doi":"10.1016/j.jajp.2025.100306","DOIUrl":"10.1016/j.jajp.2025.100306","url":null,"abstract":"<div><div>A layered composite of AA1050-AA5052 alloys was fabricated through roll bonding, and accumulative roll bonding (ARB) and subsequently subjected to friction stir processing (FSP). In this process, the annealed AA5052 and AA1050 sheets are used as raw materials. At first, preheating at 200 °C for 6 min preceded the rolling process in an induction furnace, achieving a 67 % reduction in the cross-sectional area. Then, two ARB stages were conducted. At the flow, the FSP process was conducted at constant transversal speeds of 750 rpm and 1180 rpm. Microstructural details were analyzed using optical microscopy (OM), scanning electron microscopy (SEM), and electron backscatter diffraction (EBSD). Mechanical properties were assessed through tensile test, microhardness measurement, and wear test. The results showed that recrystallization occurred due to FSP applied to the rolled sheet. The tensile strength after ARB and FSP was measured as 270 and 150 MPa, respectively. These values show an increase of 3.3 times and 1.8 times, respectively, compared to annealed AA1050. The maximum elongation after ARB and FSP was measured at about 9 and 30 %. Work hardening and grain refinement, respectively, had a significant role in increasing the elongation of the AA1050/AA5052 composites created by ARB and FSP. Furthermore, FSP enhanced the wear resistance of the AA1050-AA5052 composite created with two ARB steps by 70 %.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"11 ","pages":"Article 100306"},"PeriodicalIF":3.8,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143903677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-04-28DOI: 10.1016/j.jajp.2025.100305
M Chelladurai Asirvatham , Iain Masters , Geoff West , Paul Haney
Laser welding of aluminium tabs to nickel-plated interstitial-free (IF) steel was investigated using a high-brightness, single-mode laser with beam wobbling. The influence of interaction time, controlled by wobble amplitude and traverse speed, regulating energy distribution on weld microstructure and mechanical properties was systematically studied. Short interaction times (<25 µs) and large inter-wobble distances (>150 µm) minimized intermetallic compound (IMC) formation and maximized weld strength. Optimizing these parameters (wider wobble amplitudes of 0.6–0.8 mm and faster speeds of 75–100 mm/s) suppressed IMC-induced cracking, resulting in microstructures containing Fe-rich IMCs and Al-Fe₄Al₁₃ eutectic phases. Conversely, lower wobble amplitudes (<0.6 mm) and slower speeds (50–75 mm/s) promoted crack-prone Al-rich Fe₂Al₅ phases. Optimized welds exhibited excellent fatigue performance, withstanding 1 million cycles at 175 N, demonstrating the potential for using lighter, cost-effective aluminium busbars in battery interconnect applications.
{"title":"High-brightness laser welding with beam wobbling: Achieving high-strength Al/Steel joints for battery busbars","authors":"M Chelladurai Asirvatham , Iain Masters , Geoff West , Paul Haney","doi":"10.1016/j.jajp.2025.100305","DOIUrl":"10.1016/j.jajp.2025.100305","url":null,"abstract":"<div><div>Laser welding of aluminium tabs to nickel-plated interstitial-free (IF) steel was investigated using a high-brightness, single-mode laser with beam wobbling. The influence of interaction time, controlled by wobble amplitude and traverse speed, regulating energy distribution on weld microstructure and mechanical properties was systematically studied. Short interaction times (<25 µs) and large inter-wobble distances (>150 µm) minimized intermetallic compound (IMC) formation and maximized weld strength. Optimizing these parameters (wider wobble amplitudes of 0.6–0.8 mm and faster speeds of 75–100 mm/s) suppressed IMC-induced cracking, resulting in microstructures containing Fe-rich IMCs and Al-Fe₄Al₁₃ eutectic phases. Conversely, lower wobble amplitudes (<0.6 mm) and slower speeds (50–75 mm/s) promoted crack-prone Al-rich Fe₂Al₅ phases. Optimized welds exhibited excellent fatigue performance, withstanding 1 million cycles at 175 N, demonstrating the potential for using lighter, cost-effective aluminium busbars in battery interconnect applications.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"11 ","pages":"Article 100305"},"PeriodicalIF":3.8,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143899316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-04-22DOI: 10.1016/j.jajp.2025.100303
Dominik Walther , Leander Schmidt , Timo Räth , Klaus Schricker , Jean Pierre Bergmann , Kai-Uwe Sattler , Patrick Mäder
Welding thin steel sheets in industrial applications is difficult because joint gaps occur during the process, which can lead to weld interruptions. Such welds are considered a reject and in order to avoid the weld to interrupt it is crucial to hinder the formation of joint gaps. Especially laser beam welding is affected by the emergence of gaps. Due to the narrow laser spot, product quality is highly dependent on the alignment and positioning of the sheets. This is typically done by clamping devices, which hold the workpieces in place. However, these clamps are suited for a specific workpiece geometry and require manual redesign every time the process changes. Adaptive clamping devices instead are designed to realize a time-dependent workpiece adjustment. Modeling the joint gap behavior to realize a controller for adaptive clamps can be difficult as the influence of heating, melting, and cooling on the joint gap formation is unknown and varies due to temperature dependent physical properties. Instead, the control parameters and actions can be derived using data-driven methods. In this paper, we present a novel data-driven approach how deep learning can be utilized to manipulate the sheet position during the weld with two actuators that apply force. A temporal convolution neural network (TCN) analyzes the change of the joint gap and predicts the required force to adapt the workpiece position. The developed method has been integrated into the welding process and improves the length of the average weld seam by 39.5% compared to welds without an active adjustment and 1.4% to welds that have been adapted with a constant force.
{"title":"Deep learning-driven active sheet positioning using linear actuators in laser beam butt welding of thin steel sheets","authors":"Dominik Walther , Leander Schmidt , Timo Räth , Klaus Schricker , Jean Pierre Bergmann , Kai-Uwe Sattler , Patrick Mäder","doi":"10.1016/j.jajp.2025.100303","DOIUrl":"10.1016/j.jajp.2025.100303","url":null,"abstract":"<div><div>Welding thin steel sheets in industrial applications is difficult because joint gaps occur during the process, which can lead to weld interruptions. Such welds are considered a reject and in order to avoid the weld to interrupt it is crucial to hinder the formation of joint gaps. Especially laser beam welding is affected by the emergence of gaps. Due to the narrow laser spot, product quality is highly dependent on the alignment and positioning of the sheets. This is typically done by clamping devices, which hold the workpieces in place. However, these clamps are suited for a specific workpiece geometry and require manual redesign every time the process changes. Adaptive clamping devices instead are designed to realize a time-dependent workpiece adjustment. Modeling the joint gap behavior to realize a controller for adaptive clamps can be difficult as the influence of heating, melting, and cooling on the joint gap formation is unknown and varies due to temperature dependent physical properties. Instead, the control parameters and actions can be derived using data-driven methods. In this paper, we present a novel data-driven approach how deep learning can be utilized to manipulate the sheet position during the weld with two actuators that apply force. A temporal convolution neural network (TCN) analyzes the change of the joint gap and predicts the required force to adapt the workpiece position. The developed method has been integrated into the welding process and improves the length of the average weld seam by 39.5% compared to welds without an active adjustment and 1.4% to welds that have been adapted with a constant force.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"11 ","pages":"Article 100303"},"PeriodicalIF":3.8,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143879131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Friction Stir Additive Manufacturing (FSAM) is a promising technique for developing large, irregularly shaped components from non-fusionable aluminum alloys, such as Al-7075, while avoiding solidification defects. Studies on melting-based AM of Al-7075 have shown poor mechanical properties, whereas FSAM has demonstrated comparatively better mechanical properties, though with non-homogeneous properties. Furthermore, conventional post-welding heat treatment (PWHT) has been found to enhance microhardness and strength but significantly reduces ductility. This study addresses these challenges by employing in-process cooling FSAM and cyclic solution PWHT. Seven-layered Al-7075-T651 laminates were manufactured through FSAM, achieving a homogeneous microstructure and mechanical properties using the in-process cooling approach. The cyclic solution treatment resulted in a 38.3 % increase in hardness and a 17.17 % improvement in UTS compared to the as-welded state, without compromising ductility.
{"title":"Enhancing microhardness and tensile strength of in-process cooled Al-7075-T651 FSAM laminates without compromising ductility through PWHT","authors":"Adeel Hassan , Khurram Altaf , Naveed Ahmed , Srinivasa Rao Pedapati , Roshan Vijay Marode","doi":"10.1016/j.jajp.2025.100304","DOIUrl":"10.1016/j.jajp.2025.100304","url":null,"abstract":"<div><div>Friction Stir Additive Manufacturing (FSAM) is a promising technique for developing large, irregularly shaped components from non-fusionable aluminum alloys, such as Al-7075, while avoiding solidification defects. Studies on melting-based AM of Al-7075 have shown poor mechanical properties, whereas FSAM has demonstrated comparatively better mechanical properties, though with non-homogeneous properties. Furthermore, conventional post-welding heat treatment (PWHT) has been found to enhance microhardness and strength but significantly reduces ductility. This study addresses these challenges by employing in-process cooling FSAM and cyclic solution PWHT. Seven-layered Al-7075-T651 laminates were manufactured through FSAM, achieving a homogeneous microstructure and mechanical properties using the in-process cooling approach. The cyclic solution treatment resulted in a 38.3 % increase in hardness and a 17.17 % improvement in UTS compared to the as-welded state, without compromising ductility.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"11 ","pages":"Article 100304"},"PeriodicalIF":3.8,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143847487","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-04-04DOI: 10.1016/j.jajp.2025.100302
Eyuel A. Lemma , João M.S. Dias , António A. Bastos , Bernardo Mascate , Ana Horovistiz
Induction brazing is emerging as a promising technique in current manufacturing processes, particularly noted for its effectiveness in the precise control of heat input, localized heating and rapid processing time. This joining technique is advantageous in industries such as heat pump and refrigeration manufacturing, which require precise and effective joining techniques, particularly for brazing copper and dissimilar metal pipes. Additionally, this technique is environmentally friendly, energy-efficient, cost-effective, and well-suited for automation.
However, studies have shown that induction brazing of copper and dissimilar metals presents several significant challenges, including thermal distortion-induced cracks due to unoptimized heat input and porosity defects stemming from inadequate filler metal penetration and suboptimal gap size between the joint, these issues can compromise joint integrity, as well as system durability and sustainability. Furthermore, the incompatible thermophysical properties of dissimilar materials and interconnectors pose substantial difficulties in achieving complete metallurgical bonding. The formation of undesirable microstructures, such as hard and brittle intermetallic compounds (IMCs), can further affect the structural, mechanical, and thermal properties of brazed joints.
This review systematically examines the effects of the most significant induction brazing process parameters on joint performance. Specifically, the effects of heat input, geometrical gap size between the joints, and composition of the filler material on the quality of brazed joints are discussed. Moreover, this review explores the induction brazing of copper with dissimilar metals, including copper with aluminum and copper with stainless steel. The impact of key process parameters on the joint quality of these materials was analyzed. Additionally, opportunities, challenges, and strategies to mitigate the challenges in induction brazing of copper and dissimilar metals are presented induction brazing are presented along with future research directions.
{"title":"Advances in induction brazing of copper and dissimilar metals: Challenges and emerging trends","authors":"Eyuel A. Lemma , João M.S. Dias , António A. Bastos , Bernardo Mascate , Ana Horovistiz","doi":"10.1016/j.jajp.2025.100302","DOIUrl":"10.1016/j.jajp.2025.100302","url":null,"abstract":"<div><div>Induction brazing is emerging as a promising technique in current manufacturing processes, particularly noted for its effectiveness in the precise control of heat input, localized heating and rapid processing time. This joining technique is advantageous in industries such as heat pump and refrigeration manufacturing, which require precise and effective joining techniques, particularly for brazing copper and dissimilar metal pipes. Additionally, this technique is environmentally friendly, energy-efficient, cost-effective, and well-suited for automation.</div><div>However, studies have shown that induction brazing of copper and dissimilar metals presents several significant challenges, including thermal distortion-induced cracks due to unoptimized heat input and porosity defects stemming from inadequate filler metal penetration and suboptimal gap size between the joint, these issues can compromise joint integrity, as well as system durability and sustainability. Furthermore, the incompatible thermophysical properties of dissimilar materials and interconnectors pose substantial difficulties in achieving complete metallurgical bonding. The formation of undesirable microstructures, such as hard and brittle intermetallic compounds (IMCs), can further affect the structural, mechanical, and thermal properties of brazed joints.</div><div>This review systematically examines the effects of the most significant induction brazing process parameters on joint performance. Specifically, the effects of heat input, geometrical gap size between the joints, and composition of the filler material on the quality of brazed joints are discussed. Moreover, this review explores the induction brazing of copper with dissimilar metals, including copper with aluminum and copper with stainless steel. The impact of key process parameters on the joint quality of these materials was analyzed. Additionally, opportunities, challenges, and strategies to mitigate the challenges in induction brazing of copper and dissimilar metals are presented induction brazing are presented along with future research directions.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"11 ","pages":"Article 100302"},"PeriodicalIF":3.8,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143807123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In response to growing environmental concerns, the transportation industry, including automotive and aerospace sectors, has emphasized improving fuel efficiency and reducing carbon dioxide emissions. To achieve significant weight reduction, multi-material design strategies that strategically utilize different materials based on their properties are being adopted. This trend highlights the need for advanced joining technologies capable of bonding dissimilar materials, such as metals and polymers or resins, while maintaining structural integrity and lightweight performance. This study investigates the direct bonding mechanism between pure titanium (Ti) and polyethylene terephthalate (PET) resin using a simple heating and pressurization process. Bubble formation at the bonding interface, a critical factor influencing joint strength, was analyzed through in-situ observation. Results show that controlled bubble dynamics enhance bonding by creating localized pressure, while excessive bubbles act as defects. Optimal bonding conditions were identified at 200–300 °C with relatively high bonding shear stress. X-ray photoelectron spectroscopy revealed the formation of Ti-C bonds, confirming strong chemical interactions at the interface. Additionally, pyrolysis gas chromatography-mass spectrometry identified ethylene glycol as a key component in bubble generation during thermal decomposition of PET. The findings highlight the significance of surface preparation, thermal control, and bubble management in achieving high bonding strength. This research provides insights into sustainable and efficient methods of dissimilar materials that can improve recyclability and support the development of advanced lightweight structures.
{"title":"Direct bonding mechanism of titanium and PET resin via heating and pressurization: Influence of bubble dynamics on bonding strength","authors":"Katsuyoshi Kondoh , Nodoka Nishimura , Kazuki Shitara , Shota Kariya , Ke Chen , Junko Umeda","doi":"10.1016/j.jajp.2025.100301","DOIUrl":"10.1016/j.jajp.2025.100301","url":null,"abstract":"<div><div>In response to growing environmental concerns, the transportation industry, including automotive and aerospace sectors, has emphasized improving fuel efficiency and reducing carbon dioxide emissions. To achieve significant weight reduction, multi-material design strategies that strategically utilize different materials based on their properties are being adopted. This trend highlights the need for advanced joining technologies capable of bonding dissimilar materials, such as metals and polymers or resins, while maintaining structural integrity and lightweight performance. This study investigates the direct bonding mechanism between pure titanium (Ti) and polyethylene terephthalate (PET) resin using a simple heating and pressurization process. Bubble formation at the bonding interface, a critical factor influencing joint strength, was analyzed through in-situ observation. Results show that controlled bubble dynamics enhance bonding by creating localized pressure, while excessive bubbles act as defects. Optimal bonding conditions were identified at 200–300 °C with relatively high bonding shear stress. X-ray photoelectron spectroscopy revealed the formation of Ti-C bonds, confirming strong chemical interactions at the interface. Additionally, pyrolysis gas chromatography-mass spectrometry identified ethylene glycol as a key component in bubble generation during thermal decomposition of PET. The findings highlight the significance of surface preparation, thermal control, and bubble management in achieving high bonding strength. This research provides insights into sustainable and efficient methods of dissimilar materials that can improve recyclability and support the development of advanced lightweight structures.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"11 ","pages":"Article 100301"},"PeriodicalIF":3.8,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143738514","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}
Friction stir welding has demonstrated significant efficacy as a solid-state welding methodology for aluminum alloys, including AA6061-T6, and is extensively utilized within automotive and aerospace engineering domains. Nonetheless, conventional FSW methods often lead to uneven residual stress distributions, compromising the material's resistance to fatigue cracking. Simultaneous Double-sided Friction Stir Welding (SDFSW) was introduced to overcome this limitation, offering enhanced welding quality by welding from both sides. This study examines the influence of tool rotational velocity on the fatigue crack growth and the distribution of residual stresses in the SDFSW process applied to AA6061-T6 aluminum. Several rotational velocity combinations were employed to assess their effect on joint quality, encompassing residual stress distribution and cyclic load performance. Based on previous experiments, the SDFSW process uses upper and lower tool speeds. These are 965/965 rpm, 967/1251 rpm and 965/1555 rpm. Fatigue crack growth testing complied with ASTM E647 standards, and the residual stress distribution was assessed through the X-ray diffraction cos α method. Additional mechanical property assessments were performed, including radiographic analysis, examination of the macrostructure and microstructure, microhardness testing, evaluation of tensile strength, and fracture characterization. The findings reveal that the rotational velocity of the tool significantly impacts the weld zone's microstructure, influencing mechanical properties, residual stress distribution, and crack growth behaviors. Among the tested conditions, the tool's rotational speed of 965/1555 rpm yielded the highest tensile strength of approximately 179.82 MPa, representing about 53 % of the strength of the base material and the greatest microhardness of 85 HV. This velocity combination also demonstrated a low fatigue crack growth rate, with Paris law coefficients C and n measured at 2E-08 and 3.6931, respectively, along with a more favorable residual stress distribution.
{"title":"Fatigue crack growth and residual stress in simultaneous double-sided friction stir welded aluminum alloy AA6061-T6","authors":"Hendrato , Muizuddin Azka , M.Refai Muslih , Rifky Apriansyah , Nidya Jullanar Salman , Sulardjaka , Ilhamdi , Jos Istiyanto , Guino Verma , Andik Dwi Kurniawan , Irfan Ansori , Lukman Shalahuddin , Jean Mario Valentino , Yohanes Pringeten Dilianto Sembiring Depari , Triyono","doi":"10.1016/j.jajp.2025.100300","DOIUrl":"10.1016/j.jajp.2025.100300","url":null,"abstract":"<div><div>Friction stir welding has demonstrated significant efficacy as a solid-state welding methodology for aluminum alloys, including AA6061-T6, and is extensively utilized within automotive and aerospace engineering domains. Nonetheless, conventional FSW methods often lead to uneven residual stress distributions, compromising the material's resistance to fatigue cracking. Simultaneous Double-sided Friction Stir Welding (SDFSW) was introduced to overcome this limitation, offering enhanced welding quality by welding from both sides. This study examines the influence of tool rotational velocity on the fatigue crack growth and the distribution of residual stresses in the SDFSW process applied to AA6061-T6 aluminum. Several rotational velocity combinations were employed to assess their effect on joint quality, encompassing residual stress distribution and cyclic load performance. Based on previous experiments, the SDFSW process uses upper and lower tool speeds. These are 965/965 rpm, 967/1251 rpm and 965/1555 rpm. Fatigue crack growth testing complied with ASTM E647 standards, and the residual stress distribution was assessed through the X-ray diffraction cos α method. Additional mechanical property assessments were performed, including radiographic analysis, examination of the macrostructure and microstructure, microhardness testing, evaluation of tensile strength, and fracture characterization. The findings reveal that the rotational velocity of the tool significantly impacts the weld zone's microstructure, influencing mechanical properties, residual stress distribution, and crack growth behaviors. Among the tested conditions, the tool's rotational speed of 965/1555 rpm yielded the highest tensile strength of approximately 179.82 MPa, representing about 53 % of the strength of the base material and the greatest microhardness of 85 HV. This velocity combination also demonstrated a low fatigue crack growth rate, with Paris law coefficients C and n measured at 2E-08 and 3.6931, respectively, along with a more favorable residual stress distribution.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"11 ","pages":"Article 100300"},"PeriodicalIF":3.8,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143738513","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 : 2025-03-24DOI: 10.1016/j.jajp.2025.100299
Johannes Friedlein , Stephan Lüder , Jan Kalich , Hans Christian Schmale , Max Böhnke , Malte Schlichter , Mathias Bobbert , Gerson Meschut , Paul Steinmann , Julia Mergheim
The clinch joining process is simulated for 22 different tool- and material-combinations, using a modular axisymmetric finite element simulation model. Two ductile metals are considered for the sheets, namely the dual-phase steel HCT590X and the aluminium alloy EN AW-6014 T4. A finite elasto-plastic material model is utilised to capture the inherent large plastic strains. Moreover, it is coupled to stress-state-dependent ductile damage and failure to successfully predict possible fracture during the clinch joining process. For all 22 clinch combinations a good agreement is obtained between simulations and experiments, regarding the geometry of the clinch joint, the process force and the occurrence of material failure. This represents a significant advance in the development and comprehension of a versatile process chain resulting from joint research efforts. The validated process simulations are then applied to study the influence of the tool geometries, sheet pre-stretch, and friction. Failure is herein always observed by neck fracture. Nevertheless, detailed analyses of the stress state evolution during the joining process for various locations reveal that the material is exposed to distinctly non-proportional loading paths demanding suitable stress-state-dependent evolution laws. Moreover, even for valid joints, process-induced damage is distributed throughout the joint. Incorporating the damage-induced softening causes an accelerated failure evolution, but has less influence on the global behaviour.
{"title":"Application of stress-state-dependent ductile damage and failure model to clinch joining for a wide range of tool and material combinations","authors":"Johannes Friedlein , Stephan Lüder , Jan Kalich , Hans Christian Schmale , Max Böhnke , Malte Schlichter , Mathias Bobbert , Gerson Meschut , Paul Steinmann , Julia Mergheim","doi":"10.1016/j.jajp.2025.100299","DOIUrl":"10.1016/j.jajp.2025.100299","url":null,"abstract":"<div><div>The clinch joining process is simulated for 22 different tool- and material-combinations, using a modular axisymmetric finite element simulation model. Two ductile metals are considered for the sheets, namely the dual-phase steel HCT590X and the aluminium alloy EN AW-6014 T4. A finite elasto-plastic material model is utilised to capture the inherent large plastic strains. Moreover, it is coupled to stress-state-dependent ductile damage and failure to successfully predict possible fracture during the clinch joining process. For all 22 clinch combinations a good agreement is obtained between simulations and experiments, regarding the geometry of the clinch joint, the process force and the occurrence of material failure. This represents a significant advance in the development and comprehension of a versatile process chain resulting from joint research efforts. The validated process simulations are then applied to study the influence of the tool geometries, sheet pre-stretch, and friction. Failure is herein always observed by neck fracture. Nevertheless, detailed analyses of the stress state evolution during the joining process for various locations reveal that the material is exposed to distinctly non-proportional loading paths demanding suitable stress-state-dependent evolution laws. Moreover, even for valid joints, process-induced damage is distributed throughout the joint. Incorporating the damage-induced softening causes an accelerated failure evolution, but has less influence on the global behaviour.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"11 ","pages":"Article 100299"},"PeriodicalIF":3.8,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143738337","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}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号