Pub Date : 2024-10-04DOI: 10.1016/j.jajp.2024.100257
Hamed Aghajani Derazkola , Andrzej Kubit
This study presents a comparative analysis of friction stir welding (FSW) and underwater friction stir welding (UFSW) of AZ31 magnesium alloy in T-configuration, emphasizing the effects on heat distribution, material properties, and mechanical performance. Simulation results revealed a more uniform heat distribution in both welding techniques, with the hottest area on the advancing side. The maximum temperatures recorded at the shoulder-workpiece contact were 404 °C for FSW and 349 °C for UFSW, a 13.6 % reduction in UFSW. Material velocity at the trailing edge was 63 mm/s for FSW and 42 mm/s for UFSW, showing a 34 % decrease due to lower heat generation in UFSW. Strain rates were 450 s⁻¹ for FSW and 420 s⁻¹ for UFSW. Grain size in the stir zone was 26 micrometers for FSW and 21 micrometers for UFSW, a 19 % reduction. Ultimate tensile strength (UTS) increased by 6 % in the skin direction and 12.8 % in the flange direction for UFSW compared to FSW. SEM analysis indicated enhanced ductility in UFSW fractures. These results demonstrate UFSW's superiority in improving thermal management, microstructural properties, and mechanical performance of welded joints.
{"title":"Effects of water cooling of friction stir welding of magnesium alloy stiffness joint","authors":"Hamed Aghajani Derazkola , Andrzej Kubit","doi":"10.1016/j.jajp.2024.100257","DOIUrl":"10.1016/j.jajp.2024.100257","url":null,"abstract":"<div><div>This study presents a comparative analysis of friction stir welding (FSW) and underwater friction stir welding (UFSW) of AZ31 magnesium alloy in T-configuration, emphasizing the effects on heat distribution, material properties, and mechanical performance. Simulation results revealed a more uniform heat distribution in both welding techniques, with the hottest area on the advancing side. The maximum temperatures recorded at the shoulder-workpiece contact were 404 °C for FSW and 349 °C for UFSW, a 13.6 % reduction in UFSW. Material velocity at the trailing edge was 63 mm/s for FSW and 42 mm/s for UFSW, showing a 34 % decrease due to lower heat generation in UFSW. Strain rates were 450 s⁻¹ for FSW and 420 s⁻¹ for UFSW. Grain size in the stir zone was 26 micrometers for FSW and 21 micrometers for UFSW, a 19 % reduction. Ultimate tensile strength (UTS) increased by 6 % in the skin direction and 12.8 % in the flange direction for UFSW compared to FSW. SEM analysis indicated enhanced ductility in UFSW fractures. These results demonstrate UFSW's superiority in improving thermal management, microstructural properties, and mechanical performance of welded joints.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"10 ","pages":"Article 100257"},"PeriodicalIF":3.8,"publicationDate":"2024-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142421591","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}
The continuous drive friction welding (CDFW) stands out for its low energy consumption within the welding realm. Polyetheretherketone (PEEK) represents a high-performance engineering thermoplastic, falling under the polyaryletherketone family. Renowned for its outstanding mechanical, thermal, and chemical attributes, PEEK finds utility across a diverse array of industries. However, the discovery of numerous voids at the weld interface has revealed limitations in the mechanical properties of PEEK welded samples. This study introduces an innovative approach named progressively increased welding area (PIWA) method, to mitigate voids within the weld interface. In general, the Taguchi method was used to optimize the process parameters of CDFW of dissimilar PEEK round rods to reduce random efforts by the trial-and-error method. It was found that the proposed PIWA method can definitely enhance the bending strength of rotational friction welded samples due to reduction of voids inside the weld interface. The optimal process parameters for the CDFW with the PIWA method involve a rotational speed of 2500 rpm, a cone angle of 120°, a cone top width of 8 mm, and a feed rate of 0.1 mm/s. The most influential factor affecting the bending strength of the PEEK welded samples is the feed rate, followed by cone angle, rotational speed, and cone top width. Specifically, the contribution ratios for feed rate, cone angle, rotational speed, and cone top width are about 71 %, 20 %, 7 %, and 2 %, respectively. The confirmation tests showed that the bending strength of the PEEK welded samples using optimal process parameters can be increased by approximately 68 % compared with the maximum bending strength of 180 MPa using the conventional method with a cone angle of 180° The proposed PIWA method has industrial applicability and practical value because this technique can enhance the mechanical properties of PEEK welded samples under low environmental pollution and energy consumption.
{"title":"Enhancing bending strength in continuous drive friction welding of PEEK polymer cylinders through the innovative progressively increased welding area method","authors":"Chil-Chyuan Kuo , Hua-Xhin Liang , Song-Hua Huang , Armaan Farooqui , Shih-Feng Tseng","doi":"10.1016/j.jajp.2024.100255","DOIUrl":"10.1016/j.jajp.2024.100255","url":null,"abstract":"<div><div>The continuous drive friction welding (CDFW) stands out for its low energy consumption within the welding realm. Polyetheretherketone (PEEK) represents a high-performance engineering thermoplastic, falling under the polyaryletherketone family. Renowned for its outstanding mechanical, thermal, and chemical attributes, PEEK finds utility across a diverse array of industries. However, the discovery of numerous voids at the weld interface has revealed limitations in the mechanical properties of PEEK welded samples. This study introduces an innovative approach named progressively increased welding area (PIWA) method, to mitigate voids within the weld interface. In general, the Taguchi method was used to optimize the process parameters of CDFW of dissimilar PEEK round rods to reduce random efforts by the trial-and-error method. It was found that the proposed PIWA method can definitely enhance the bending strength of rotational friction welded samples due to reduction of voids inside the weld interface. The optimal process parameters for the CDFW with the PIWA method involve a rotational speed of 2500 rpm, a cone angle of 120°, a cone top width of 8 mm, and a feed rate of 0.1 mm/s. The most influential factor affecting the bending strength of the PEEK welded samples is the feed rate, followed by cone angle, rotational speed, and cone top width. Specifically, the contribution ratios for feed rate, cone angle, rotational speed, and cone top width are about 71 %, 20 %, 7 %, and 2 %, respectively. The confirmation tests showed that the bending strength of the PEEK welded samples using optimal process parameters can be increased by approximately 68 % compared with the maximum bending strength of 180 MPa using the conventional method with a cone angle of 180° The proposed PIWA method has industrial applicability and practical value because this technique can enhance the mechanical properties of PEEK welded samples under low environmental pollution and energy consumption.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"10 ","pages":"Article 100255"},"PeriodicalIF":3.8,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142421589","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 : 2024-09-27DOI: 10.1016/j.jajp.2024.100256
Anand Mohan, Pasquale Franciosa, Dan Dai, Dariusz Ceglarek
Battery housing (BH) in modern electric vehicles must meet demanding functional requirements. The design and geometry of the BH become intricate to prevent damage during collisions and to ensure absolute impermeability to gases and water during operation. Moreover, in the pursuit of a lightweight BH, manufacturers rely on high-strength 6xxx aluminium alloys, posing significant challenges for the welding processes. It is estimated that up to 30 m of weld length is required during the construction of battery housings including joining the lid and under-shield to the main structural frame and joining the ribs to the frame for standard vehicles. Due to the increasing use of thin sheets for lightweighting the structure, thermal-induced buckling may occur and generate critical dimensional unconformities going beyond design tolerances. This underpins the need to optimise fixturing design to control thermal-induced buckling.
This paper goes beyond the state-of-the-art “N-2-1″ approaches for fixturing thin and deformable parts and proposes the new principle of “unilateral N-2-1 fixturing”. The driving idea is adding unilateral restraints to the direction of thermal contraction, which ultimately causes buckling; and, keeping the direction where the thermal expansion occurs in a free state. The methodology is based on three main steps: (1) physics-based modelling of parts and fixtures using a thermo-mechanical FEA simulation; (2) calibration of the weld heat source using metallographic data; (3) validation using optical scanning technology. The methodology was demonstrated during the laser beam welding of a high-strength aluminium 6xxx thin deformable lid to a rigid high-strength 6xxx aluminium extrusion frame. Results indicated that the thermal induced buckling deformation was reduced from 15 mm, when using the state-of-the-art fixturing approach, to approximately 2 mm with the proposed methodology.
{"title":"A novel approach to control thermal induced buckling during laser welding of battery housing through a unilateral N-2-1 fixturing principle","authors":"Anand Mohan, Pasquale Franciosa, Dan Dai, Dariusz Ceglarek","doi":"10.1016/j.jajp.2024.100256","DOIUrl":"10.1016/j.jajp.2024.100256","url":null,"abstract":"<div><div>Battery housing (BH) in modern electric vehicles must meet demanding functional requirements. The design and geometry of the BH become intricate to prevent damage during collisions and to ensure absolute impermeability to gases and water during operation. Moreover, in the pursuit of a lightweight BH, manufacturers rely on high-strength 6xxx aluminium alloys, posing significant challenges for the welding processes. It is estimated that up to 30 m of weld length is required during the construction of battery housings including joining the lid and under-shield to the main structural frame and joining the ribs to the frame for standard vehicles. Due to the increasing use of thin sheets for lightweighting the structure, thermal-induced buckling may occur and generate critical dimensional unconformities going beyond design tolerances. This underpins the need to optimise fixturing design to control thermal-induced buckling.</div><div>This paper goes beyond the state-of-the-art “N-2-1″ approaches for fixturing thin and deformable parts and proposes the new principle of “unilateral N-2-1 fixturing”. The driving idea is adding unilateral restraints to the direction of thermal contraction, which ultimately causes buckling; and, keeping the direction where the thermal expansion occurs in a free state. The methodology is based on three main steps: (1) physics-based modelling of parts and fixtures using a thermo-mechanical FEA simulation; (2) calibration of the weld heat source using metallographic data; (3) validation using optical scanning technology. The methodology was demonstrated during the laser beam welding of a high-strength aluminium 6xxx thin deformable lid to a rigid high-strength 6xxx aluminium extrusion frame. Results indicated that the thermal induced buckling deformation was reduced from 15 mm, when using the state-of-the-art fixturing approach, to approximately 2 mm with the proposed methodology.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"10 ","pages":"Article 100256"},"PeriodicalIF":3.8,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142421590","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 : 2024-09-20DOI: 10.1016/j.jajp.2024.100254
E. Scharifi , M. Kahlmeyer , A. Suckau , S. Lotz , N. Sommer , R. Delir Nazarlou , D. Bailly , U. Weidig , K. Steinhoff
Friction-stir-welding process has become an established solid-state technique for joining of dissimilar lightweight materials over the past decade by overcoming fundamental welding challenges such as solidification cracking, phase segregation and surface oxidation. Despite these unique capabilities, the resulting microstructure feature in the weld zone consisting of fine grains with a high dislocation density, challenges further heat treatment and forming processes. Hence, a high solution annealing temperature results in degradation of the adjusted microstructure and in a lower to reduced mechanical properties in case of dissimilar joints of precipitation-hardenable aluminum alloys. Subsequent hot forming therefore involves a great effort and requires further heat treatment steps. Thus, the present study investigates the effect of a recently introduced novel thermo-mechanical forming process on local deformation behavior of similar as well as dissimilar joints processed by friction-stir-welding technique of thin-walled AA6082 and AA7075 blanks. To avoid the complete elimination of the adjusted microstructure, the welding process is performed after a thermo-mechanical process consisting of solution annealing, die cooling and peak aging. Uniaxial tensile tests are then carried out at high strain rates ranging from = 40 s-1 to = 400 s-1. The results show an increase in yield and ultimate tensile strength as well as in total elongation after failure with increasing strain rates. As the strain rate increases, the flow stress of similar weld of AA7075 is higher than those of AA6082 and the dissimilar weld of AA6082 and AA7075. Local deformation measurements reveal higher strain localization in the welded zone for similar welds, which leads to micro-crack initiation and failure due to strain accumulation. Microstructure analysis shows very fine equiaxed grain structure in the nugget zone and homogenous distribution of precipitates after friction stir welding process, which explain the plastic deformation behavior.
{"title":"High strain rate tensile deformation of similar and dissimilar AA6082 and AA7075 friction-stir-welded blanks","authors":"E. Scharifi , M. Kahlmeyer , A. Suckau , S. Lotz , N. Sommer , R. Delir Nazarlou , D. Bailly , U. Weidig , K. Steinhoff","doi":"10.1016/j.jajp.2024.100254","DOIUrl":"10.1016/j.jajp.2024.100254","url":null,"abstract":"<div><div>Friction-stir-welding process has become an established solid-state technique for joining of dissimilar lightweight materials over the past decade by overcoming fundamental welding challenges such as solidification cracking, phase segregation and surface oxidation. Despite these unique capabilities, the resulting microstructure feature in the weld zone consisting of fine grains with a high dislocation density, challenges further heat treatment and forming processes. Hence, a high solution annealing temperature results in degradation of the adjusted microstructure and in a lower to reduced mechanical properties in case of dissimilar joints of precipitation-hardenable aluminum alloys. Subsequent hot forming therefore involves a great effort and requires further heat treatment steps. Thus, the present study investigates the effect of a recently introduced novel thermo-mechanical forming process on local deformation behavior of similar as well as dissimilar joints processed by friction-stir-welding technique of thin-walled AA6082 and AA7075 blanks. To avoid the complete elimination of the adjusted microstructure, the welding process is performed after a thermo-mechanical process consisting of solution annealing, die cooling and peak aging. Uniaxial tensile tests are then carried out at high strain rates ranging from <span><math><mover><mrow><mi>ε</mi></mrow><mi>˙</mi></mover></math></span> = 40 s<sup>-1</sup> to <span><math><mover><mrow><mi>ε</mi></mrow><mi>˙</mi></mover></math></span> = 400 s<sup>-1</sup>. The results show an increase in yield and ultimate tensile strength as well as in total elongation after failure with increasing strain rates. As the strain rate increases, the flow stress of similar weld of AA7075 is higher than those of AA6082 and the dissimilar weld of AA6082 and AA7075. Local deformation measurements reveal higher strain localization in the welded zone for similar welds, which leads to micro-crack initiation and failure due to strain accumulation. Microstructure analysis shows very fine equiaxed grain structure in the nugget zone and homogenous distribution of precipitates after friction stir welding process, which explain the plastic deformation behavior.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"10 ","pages":"Article 100254"},"PeriodicalIF":3.8,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142323138","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 : 2024-09-14DOI: 10.1016/j.jajp.2024.100253
Moritz Mascher, Pia Wagner, Christian Hopmann
Plastic/metal hybrid components made of amorphous thermoplastics such as polycarbonate and light metals such as aluminum offer potential to be used in modern automotive headlights to meet the high requirements for tolerances and surface quality. A microform-fit joining approach is used to join plastics and metals, which combines the advantages of material-fit and form-fit joining processes while at the same time avoiding some of the disadvantages of the respective joining approaches, such as stress peaks or the use of additional chemicals. For this purpose, the light metal component is microstructured through laser ablation. To ensure the functional safety of electrical components, the media tightness of the hybrid component is tested with a pressure drop test. An influence of the structure arrangement, the structure spacing and the molding compound on the media tightness can be determined. The highest media tightness can be achieved with a ring-shaped structural arrangement in which the microstructures are orientated orthogonally to the outlet direction of the test medium. The media permeability of a ring-shaped structure arrangement with a structure spacing of 500 µm is 0.42 cm3/s for test specimens made of aluminum and polycarbonate. As the value is below the threshold value of 12 cm3/s, watertightness up to an overpressure of at least 0.5 bar can be concluded.
{"title":"Investigation of the media tightness of a microform-fitted plastic/light metal composite","authors":"Moritz Mascher, Pia Wagner, Christian Hopmann","doi":"10.1016/j.jajp.2024.100253","DOIUrl":"10.1016/j.jajp.2024.100253","url":null,"abstract":"<div><p>Plastic/metal hybrid components made of amorphous thermoplastics such as polycarbonate and light metals such as aluminum offer potential to be used in modern automotive headlights to meet the high requirements for tolerances and surface quality. A microform-fit joining approach is used to join plastics and metals, which combines the advantages of material-fit and form-fit joining processes while at the same time avoiding some of the disadvantages of the respective joining approaches, such as stress peaks or the use of additional chemicals. For this purpose, the light metal component is microstructured through laser ablation. To ensure the functional safety of electrical components, the media tightness of the hybrid component is tested with a pressure drop test. An influence of the structure arrangement, the structure spacing and the molding compound on the media tightness can be determined. The highest media tightness can be achieved with a ring-shaped structural arrangement in which the microstructures are orientated orthogonally to the outlet direction of the test medium. The media permeability of a ring-shaped structure arrangement with a structure spacing of 500 µm is 0.42 cm<sup>3</sup>/s for test specimens made of aluminum and polycarbonate. As the value is below the threshold value of 12 cm<sup>3</sup>/s, watertightness up to an overpressure of at least 0.5 bar can be concluded.</p></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"10 ","pages":"Article 100253"},"PeriodicalIF":3.8,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666330924000694/pdfft?md5=99e3d6f0213567ef7569418dfa402a69&pid=1-s2.0-S2666330924000694-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142240771","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 : 2024-09-10DOI: 10.1016/j.jajp.2024.100252
Marcela Matus-Aguirre , Benoît Cosson , Christian Garnier , Fabrice Schmidt , André Chateau Akué-Asséko , France Chabert
Welding high-performance thermoplastics has gained popularity across various industries such as automotive, aerospace, and medical. Laser transmission welding (LTW) has emerged as an effective method for joining thermoplastic parts due to its precise control and high joint quality. PAEK (polyaryletherketone) are wide spreading over various industrial applications as a substitute to metals and thermosets when high durability and performance are required. Polyetherketoneketone (PEKK) is one of these PAEK and it has received less attention than PEEK until now. PEKK, being a semi-crystalline thermoplastic, requires additional care during processing due to its propensity to crystallize. This study presents both experimental and numerical investigations into LTW of PEKK molded parts, aiming to understand the influence of welding parameters and crystallinity on weld joint morphology and mechanical properties. PEKK plates, prepared in amorphous and semi-crystalline states, are subjected to LTW using a 975 nm diode laser. Material characterization confirms differences in crystallinity between the samples, which affect their thermal and optical properties, which are crucial for welding. Welding tests are conducted with varying laser power (between 75 and 95 W) and semi-transparent part thickness (2 and 4 mm). The morphology of joints is analysed. Assemblies undergo post-weld annealing treatment to examine its influence on weld crystallinity and consequent mechanical properties. Results reveal an anisotropic distribution of crystallinity within the heat-affected zone (HAZ). The depths of the molten layer (ML) and semi-crystalline layer (scL) vary with laser power and assembly type. A notable decrease in weld strength with laser power is highlighted, while annealing leads to enhanced crystallinity and improved weld strength. Despite variations, high weld strengths are achieved with annealing. Computational modelling elucidates the complex interplay between laser irradiation, temperature distribution, and crystallization kinetics observed experimentally. Overall, this comprehensive investigation provides valuable insights into optimizing LTW parameters for PEKK parts.
{"title":"Characterization and modeling of laser transmission welded polyetherketoneketone (PEKK) joints: Influence of process parameters and annealing on weld properties","authors":"Marcela Matus-Aguirre , Benoît Cosson , Christian Garnier , Fabrice Schmidt , André Chateau Akué-Asséko , France Chabert","doi":"10.1016/j.jajp.2024.100252","DOIUrl":"10.1016/j.jajp.2024.100252","url":null,"abstract":"<div><p>Welding high-performance thermoplastics has gained popularity across various industries such as automotive, aerospace, and medical. Laser transmission welding (LTW) has emerged as an effective method for joining thermoplastic parts due to its precise control and high joint quality. PAEK (polyaryletherketone) are wide spreading over various industrial applications as a substitute to metals and thermosets when high durability and performance are required. Polyetherketoneketone (PEKK) is one of these PAEK and it has received less attention than PEEK until now. PEKK, being a semi-crystalline thermoplastic, requires additional care during processing due to its propensity to crystallize. This study presents both experimental and numerical investigations into LTW of PEKK molded parts, aiming to understand the influence of welding parameters and crystallinity on weld joint morphology and mechanical properties. PEKK plates, prepared in amorphous and semi-crystalline states, are subjected to LTW using a 975 nm diode laser. Material characterization confirms differences in crystallinity between the samples, which affect their thermal and optical properties, which are crucial for welding. Welding tests are conducted with varying laser power (between 75 and 95 W) and semi-transparent part thickness (2 and 4 mm). The morphology of joints is analysed. Assemblies undergo post-weld annealing treatment to examine its influence on weld crystallinity and consequent mechanical properties. Results reveal an anisotropic distribution of crystallinity within the heat-affected zone (HAZ). The depths of the molten layer (ML) and semi-crystalline layer (scL) vary with laser power and assembly type. A notable decrease in weld strength with laser power is highlighted, while annealing leads to enhanced crystallinity and improved weld strength. Despite variations, high weld strengths are achieved with annealing. Computational modelling elucidates the complex interplay between laser irradiation, temperature distribution, and crystallization kinetics observed experimentally. Overall, this comprehensive investigation provides valuable insights into optimizing LTW parameters for PEKK parts.</p></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"10 ","pages":"Article 100252"},"PeriodicalIF":3.8,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666330924000682/pdfft?md5=24dcb89e6cc6e498459bac99b4908582&pid=1-s2.0-S2666330924000682-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142240770","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}
The escalation in electric vehicle (EV) adoption necessitates advanced laser joining techniques for critical battery pack components. However, using a standard Gaussian single-mode laser for joining similar and dissimilar material combinations e.g. aluminium/aluminium (Al/Al), aluminium/copper (Al/Cu) for tab-to-busbar connections often led to defects such as cracks and intermetallic compound (IMC) formation. This paper investigates using a dual-mode laser consisting of a core and ring to overcome these issues. In this research, 0.3 mm Al and Cu tabs were welded with 1.5 mm Al and Cu busbars using a 6 kW IPG dual-mode laser at a high welding speed of 1 m s-1. The study focussed on the effects of dual-mode parameters (i.e. core and ring beam power) and welding speed on tab-to-busbar connections, analysing the interplay between electrical contact resistance, temperature and IMC formation through electrical resistance tests, elemental and strength analysis. The results show, that using the ring beam along with the core beam reduces excessive melting and evaporation of Al and minimises the intermixing of Al and Cu solid solutions in the joint. In the Cu tab-to-Al busbar joint, increasing the ring beam intensity effectively reduces the convexity defect found with single-mode beam attributed to improved keyhole stability. Overall, in dual-mode laser welding, the ring beam protects the keyhole and reduces the IMC formation, while the core beam, with its high peak intensities, controls the penetration depth. This necessitates balancing both core and ring beam intensities for optimal weld quality. Further, the joint resistance for Cu tab-to-Cu busbar (51.90 μΩ) joint was the lowest followed by Cu tab-to-Al busbar (68.38 μΩ) joint, Al tab-to-Cu busbar (84.44 μΩ) joint and Al tab-to-Al busbar (114.12 μΩ) joint.
随着电动汽车（EV）的普及，电池组关键部件需要采用先进的激光连接技术。然而，使用标准的高斯单模激光器来连接类似和不同的材料组合，例如铝/铝（Al/Al）、铝/铜（Al/Cu）的凸片与母线连接，往往会导致裂纹和金属间化合物（IMC）形成等缺陷。本文研究使用由核心和环组成的双模激光器来克服这些问题。在这项研究中，使用 6 kW IPG 双模激光器，以 1 m s-1 的高速焊接，将 0.3 mm 铝和铜焊片与 1.5 mm 铝和铜母线焊接在一起。研究的重点是双模参数（即核心和环形光束功率）和焊接速度对片与母线连接的影响，并通过电阻测试、元素和强度分析来分析电接触电阻、温度和 IMC 形成之间的相互作用。结果表明，在使用芯梁的同时使用环梁可减少铝的过度熔化和蒸发，并最大限度地减少接头中铝和铜固溶体的混合。在铜片与铝母线的焊接中，环形光束强度的增加有效地减少了单模光束下的凸凹缺陷，这归功于键孔稳定性的提高。总之，在双模激光焊接中，环形光束可保护键孔并减少 IMC 的形成，而具有高强度峰值的核心光束则可控制穿透深度。这就需要平衡核心光束和环形光束的强度，以获得最佳焊接质量。此外，铜片对铜母线（51.90 μΩ）接头的接头电阻最小，其次是铜片对铝母线（68.38 μΩ）接头、铝片对铜母线（84.44 μΩ）接头和铝片对铝母线（114.12 μΩ）接头。
{"title":"Dual-mode laser beam welding of similar and dissimilar material tab-to-busbar for electric vehicle battery pack","authors":"Nikhil Kumar , Venkat Vivek Pamarthi , Christopher Harris , Elliot Burbidge , Iain Masters","doi":"10.1016/j.jajp.2024.100250","DOIUrl":"10.1016/j.jajp.2024.100250","url":null,"abstract":"<div><p>The escalation in electric vehicle (EV) adoption necessitates advanced laser joining techniques for critical battery pack components. However, using a standard Gaussian single-mode laser for joining similar and dissimilar material combinations e.g. aluminium/aluminium (Al/Al), aluminium/copper (Al/Cu) for tab-to-busbar connections often led to defects such as cracks and intermetallic compound (IMC) formation. This paper investigates using a dual-mode laser consisting of a core and ring to overcome these issues. In this research, 0.3 mm Al and Cu tabs were welded with 1.5 mm Al and Cu busbars using a 6 kW IPG dual-mode laser at a high welding speed of 1 m s<sup>-1</sup>. The study focussed on the effects of dual-mode parameters (i.e. core and ring beam power) and welding speed on tab-to-busbar connections, analysing the interplay between electrical contact resistance, temperature and IMC formation through electrical resistance tests, elemental and strength analysis. The results show, that using the ring beam along with the core beam reduces excessive melting and evaporation of Al and minimises the intermixing of Al and Cu solid solutions in the joint. In the Cu tab-to-Al busbar joint, increasing the ring beam intensity effectively reduces the convexity defect found with single-mode beam attributed to improved keyhole stability. Overall, in dual-mode laser welding, the ring beam protects the keyhole and reduces the IMC formation, while the core beam, with its high peak intensities, controls the penetration depth. This necessitates balancing both core and ring beam intensities for optimal weld quality. Further, the joint resistance for Cu tab-to-Cu busbar (51.90 μΩ) joint was the lowest followed by Cu tab-to-Al busbar (68.38 μΩ) joint, Al tab-to-Cu busbar (84.44 μΩ) joint and Al tab-to-Al busbar (114.12 μΩ) joint.</p></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"10 ","pages":"Article 100250"},"PeriodicalIF":3.8,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666330924000669/pdfft?md5=5530b89d797a952fb8a294d5495f390b&pid=1-s2.0-S2666330924000669-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142151887","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 : 2024-09-04DOI: 10.1016/j.jajp.2024.100251
M. Winkler , C. Rößler , N. Harriehausen , S. Jüttner , D. Schmicker , F. Trommer
The present publication deals with an energy-oriented approach to the statistical analysis of rotational friction welding processes. To illustrate the methodological approach, it is applied to investigate the effects of energy flow on material flow behavior and joint quality during friction welding of an AA6060 alloy with a low-alloy 16MnCr5 filler steel. The influences of the setting parameters on the energetic states are first analyzed by means of an initial screening. The evaluation using process simulation and statistical methods enables the generation of regressive response surfaces for the friction power, the friction time and the resulting induced friction energy. Based on these findings, a second experimental field is formed and evaluated, which considers the interaction between the energy input of the frictioning stage and the workpiece forging. This new approach results in the functional separation of the frictioning and forging stage, which eliminates the usual statistical interaction effects and thus facilitates analysis and optimization. The qualitative result variable required for the purpose of interpreting the results is the ultimate tensile strength of the friction-welded joint. Additionally determined hardness curves provide information about the properties of the thermally influenced zone and strength-relevant process sequences. The result is that, in addition to the amount of energy induced, the frictional power with which the former is induced also has a considerable influence on the joint strength, as it influences the material flow and the properties of the joining zone.
{"title":"An energetic approach to the statistical analysis and optimization of friction welding processes applied to an aluminum-steel-joint","authors":"M. Winkler , C. Rößler , N. Harriehausen , S. Jüttner , D. Schmicker , F. Trommer","doi":"10.1016/j.jajp.2024.100251","DOIUrl":"10.1016/j.jajp.2024.100251","url":null,"abstract":"<div><p>The present publication deals with an energy-oriented approach to the statistical analysis of rotational friction welding processes. To illustrate the methodological approach, it is applied to investigate the effects of energy flow on material flow behavior and joint quality during friction welding of an AA6060 alloy with a low-alloy 16MnCr5 filler steel. The influences of the setting parameters on the energetic states are first analyzed by means of an initial screening. The evaluation using process simulation and statistical methods enables the generation of regressive response surfaces for the friction power, the friction time and the resulting induced friction energy. Based on these findings, a second experimental field is formed and evaluated, which considers the interaction between the energy input of the frictioning stage and the workpiece forging. This new approach results in the functional separation of the frictioning and forging stage, which eliminates the usual statistical interaction effects and thus facilitates analysis and optimization. The qualitative result variable required for the purpose of interpreting the results is the ultimate tensile strength of the friction-welded joint. Additionally determined hardness curves provide information about the properties of the thermally influenced zone and strength-relevant process sequences. The result is that, in addition to the amount of energy induced, the frictional power with which the former is induced also has a considerable influence on the joint strength, as it influences the material flow and the properties of the joining zone.</p></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"10 ","pages":"Article 100251"},"PeriodicalIF":3.8,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666330924000670/pdfft?md5=68ec14bd4d9234f6c5d6a20de1f68bbd&pid=1-s2.0-S2666330924000670-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142167346","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}
Achieving strong direct joining between steel and polymers through mechanical interlocking is crucial for developing multi-material structures, particularly in the automotive and aerospace industries. This study synthesized micro-scale structures on a pure Fe substrate (simulating interstitial-free (IF) steel) for mechanical interlocking with thermoplastic parts. Numerous submillimeter-scale Fe/TiB2 composite particles were in-situ synthesized by laser scanning on the Fe-Ti-B powder mixture and well-bonded with the Fe substrate. The effects of powder composition (TiB2 volume fraction) on the morphology, microstructure, and joint strength with PA6 were investigated. A TiB2 volume fraction over 60 % was essential for the formation of the composite particles promoted by a TiB2 skeletal structure. Higher TiB2 volume fractions increased the area fraction of the composite particles and decreased the bonding ratio (adhesive) of the particles with the substrate due to poor adhesiveness at the edge of the laser-scanning line. A wider high-temperature region was generated at a higher TiB2 volume fraction, suggesting that the reaction heat to form TiB2 assisted the bonding of the particles with the substrate at the edge of the laser scanning line. The Fe/PA6 joint strength increased to approximately 30 MPa with increasing the TiB2 volume fraction to 100 % and showed a linear correlation with the product of particle area fraction and bonding ratio. A higher TiB2 volume fraction was preferable for enhancing the joint strength via the micro-scale structures synthesized by laser scanning on the Fe-Ti-B powder mixture. A combination of the micro-structuring process using a high fraction of TiB2 with advanced joining technologies will contribute to manufacturing high-strength Fe/polymer hybrid parts.
{"title":"Fe/polymer joining via Fe/TiB2 composite structures via in-situ laser-induced reaction of Fe-Ti-B system: Effect of powder composition","authors":"Shaoyun Zhou, Koki Omiya, Yuto Ueda, Asuka Suzuki, Naoki Takata, Makoto Kobashi","doi":"10.1016/j.jajp.2024.100249","DOIUrl":"10.1016/j.jajp.2024.100249","url":null,"abstract":"<div><p>Achieving strong direct joining between steel and polymers through mechanical interlocking is crucial for developing multi-material structures, particularly in the automotive and aerospace industries. This study synthesized micro-scale structures on a pure Fe substrate (simulating interstitial-free (IF) steel) for mechanical interlocking with thermoplastic parts. Numerous submillimeter-scale Fe/TiB<sub>2</sub> composite particles were in-situ synthesized by laser scanning on the Fe-Ti-B powder mixture and well-bonded with the Fe substrate. The effects of powder composition (TiB<sub>2</sub> volume fraction) on the morphology, microstructure, and joint strength with PA6 were investigated. A TiB<sub>2</sub> volume fraction over 60 % was essential for the formation of the composite particles promoted by a TiB<sub>2</sub> skeletal structure. Higher TiB<sub>2</sub> volume fractions increased the area fraction of the composite particles and decreased the bonding ratio (adhesive) of the particles with the substrate due to poor adhesiveness at the edge of the laser-scanning line. A wider high-temperature region was generated at a higher TiB<sub>2</sub> volume fraction, suggesting that the reaction heat to form TiB<sub>2</sub> assisted the bonding of the particles with the substrate at the edge of the laser scanning line. The Fe/PA6 joint strength increased to approximately 30 MPa with increasing the TiB<sub>2</sub> volume fraction to 100 % and showed a linear correlation with the product of particle area fraction and bonding ratio. A higher TiB<sub>2</sub> volume fraction was preferable for enhancing the joint strength via the micro-scale structures synthesized by laser scanning on the Fe-Ti-B powder mixture. A combination of the micro-structuring process using a high fraction of TiB<sub>2</sub> with advanced joining technologies will contribute to manufacturing high-strength Fe/polymer hybrid parts.</p></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"10 ","pages":"Article 100249"},"PeriodicalIF":3.8,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666330924000657/pdfft?md5=53be598e789d8f527444022129922e10&pid=1-s2.0-S2666330924000657-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142151888","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}
This research investigates the inherent radial non-uniformity within the rotary friction welding process, particularly concerning microstructure attributes like grain size, grain boundaries, misorientation angles, and interlayer presence along the radial axis. SS321-AA2219 rotary friction welding was carried out with and without an AA6061 interlayer. The numerical thermal model suggests increase in temperatures from the center to the periphery, due to non-uniform heat generation. Also, dissimilar material across the interface resulted in an asymmetric temperature profile along axial direction. Plastic deformation on the Aluminum side suggests dynamic recrystallization and grain refinement, whereas pronounced low-angle grain boundary (LAGB) formation near the SS side interface validates dynamic recovery. A radial non-uniformity in microstructure is observed, with metrics such as average grain size, LAGB fraction, and misorientation showing an increase from the center towards the periphery. The insertion of an interlayer alters process dynamics, manifesting in reduced temperatures and heightened forces, resulting in a more consolidated joint by enhancing the strength by 31 %. Interdiffusion of elements across the interface formed Fe-Al intermetallic compounds (IMC) confirmed with X ray diffraction. Fractography analysis elucidates the presence of rubbing marks and facet surfaces in interlayer-less joints, while joints with interlayer display sticking and dimples.
{"title":"Interfacial inhomogeneous plastic deformation during rotary friction welding of dissimilar AA2219-SS321 joint combination with AA6061 interlayer","authors":"Neeraj Kumar Mishra , S.G.K. Manikandan , Amber Shrivastava","doi":"10.1016/j.jajp.2024.100245","DOIUrl":"10.1016/j.jajp.2024.100245","url":null,"abstract":"<div><p>This research investigates the inherent radial non-uniformity within the rotary friction welding process, particularly concerning microstructure attributes like grain size, grain boundaries, misorientation angles, and interlayer presence along the radial axis. SS321-AA2219 rotary friction welding was carried out with and without an AA6061 interlayer. The numerical thermal model suggests increase in temperatures from the center to the periphery, due to non-uniform heat generation. Also, dissimilar material across the interface resulted in an asymmetric temperature profile along axial direction. Plastic deformation on the Aluminum side suggests dynamic recrystallization and grain refinement, whereas pronounced low-angle grain boundary (LAGB) formation near the SS side interface validates dynamic recovery. A radial non-uniformity in microstructure is observed, with metrics such as average grain size, LAGB fraction, and misorientation showing an increase from the center towards the periphery. The insertion of an interlayer alters process dynamics, manifesting in reduced temperatures and heightened forces, resulting in a more consolidated joint by enhancing the strength by 31 %. Interdiffusion of elements across the interface formed Fe-Al intermetallic compounds (IMC) confirmed with X ray diffraction. Fractography analysis elucidates the presence of rubbing marks and facet surfaces in interlayer-less joints, while joints with interlayer display sticking and dimples.</p></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"10 ","pages":"Article 100245"},"PeriodicalIF":3.8,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S266633092400061X/pdfft?md5=449a36bd2bf29ba4780431b636df7c85&pid=1-s2.0-S266633092400061X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142096133","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}
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