Article
Chemistry, Physical
Mohamed M. Z. Ahmed, Mohamed M. El-Sayed Seleman, Essam Ahmed, Kamel Touileb, Ibrahim Albaijan
Summary: Friction stir spot welding is an important variant of the friction stir welding process, particularly for spot welding different thickness sheets in automotive applications. In this study, thin sheets of AA6082-T6 with different thicknesses (1 mm and 2 mm) were successfully welded using FSSW at various rotation speeds. Macro- and microstructural investigations, hardness tests, and tensile shear tests were conducted to evaluate the quality and mechanical properties of the FSSW joints. The results showed that defect-free spot joints can be achieved within a wide range of rotation speeds (400-1000 rpm), and the best welding condition was found to be 600 rpm for achieving different thin sheet thicknesses spot joints with desirable properties.
Article
Materials Science, Multidisciplinary
M. Balamurugan, S. Gopi, Dhanesh G. Mohan
Summary: In this research, a new filler added friction stir spot welding (FAFSSW) process was adopted to weld dissimilar aluminium alloys of AA5052 with AA6061, using five different tapered tool pins to enhance the mechanical and metallurgical properties of the joints. The results showed that the FAFSSW joint exhibited higher strength and a fine grain structure compared to normal FSSW joints, with magnesium (Mg) powder serving as the filler material.
MATERIALS RESEARCH EXPRESS
(2021)
Article
Materials Science, Multidisciplinary
Xiaopei Wang, Yoshiaki Morisada, Hidetoshi Fujii
Summary: In this study, dissimilar welding of AZ31/ZK60 magnesium alloys was successfully achieved using double-sided friction stir spot welding with adjustable probes, resulting in a strong joint with improved properties.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2021)
Article
Materials Science, Characterization & Testing
Sare Celik, Fatmagul Tolun
Summary: In this study, the effect of double-sided friction stir welding on AA5754 Al alloy was investigated, with the best welding performance observed at a tool rotational speed, feed rate, and tool tilt angle of 450 rpm, 50 mm x min(-1), and 1 degree, respectively.
Article
Chemistry, Physical
Koki Kumamoto, Tsuyoshi Kosaka, Tatsuya Kobayashi, Ikuo Shohji, Yuichiro Kamakoshi
Summary: In this study, dissimilar A6061/Galvannealed steel joints were fabricated by friction stir spot welding, revealing the formation of Fe4Al13 phases and a stirred layer at the joint interface. The total welding time had minimal effects on tensile shear and tensile shear fatigue properties, with fatigue fractures occurring in the A6061 matrix and at the joint interface.
Article
Materials Science, Multidisciplinary
Ivan S. Zuiko, Sergey Malopheyev, Sergey Mironov, Sergey Betsofen, Rustam Kaibyshev
Summary: The macro-scale distribution of secondary precipitates in friction-stir-welded 2519 aluminium alloy was found to vary within the stir zone due to local variations in welding temperature and cooling rate. Precipitation coarsening was most pronounced at the weld root, while dissolution was enhanced at the upper weld surface. Reprecipitation phenomena were most prominent in the weld nugget.
Article
Materials Science, Multidisciplinary
Zhe Liu, Zhiyu Fan, Li Liu, Shu Miao, Zhicheng Lin, Chungui Wang, Yunqiang Zhao, Renlong Xin, Chunlin Dong
Summary: In this study, 1 mm-thick AZ31 magnesium alloy sheets were joined by refill friction stir spot welding. The metallurgical features, microstructure, texture, and mechanical response of the spot-welded joints were investigated, and the effect of welding parameters on joint performance was evaluated. The results showed that the highest lap shear strength was achieved with a rotational speed of 1500 rpm and a plunge depth of 1.4 mm. A fine-grain structure was observed in the stir zone, and the grain size decreased with lower rotational speed and plunge depth. Furthermore, strain localization was observed during tensile deformation in the spot weld, and the mechanism behind this phenomenon was discussed.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Materials Science, Multidisciplinary
Kethavath Kranthi Kumar, Adepu Kumar, Sarvana Sundar
Summary: This study investigates the microstructure characteristics, tensile properties, and work hardening behavior of friction stir welding (FSW) AA5083-AA6061 dissimilar aluminum alloys under different cooling conditions. The results show that water-cooled FSW joints exhibited higher ultimate tensile strength (UTS) and enhanced strain hardening coefficient and work hardening rate compared to air-cooled FSW joints. The microstructure evolution and texture components primarily evolved in FSW samples were also analyzed.
MATERIALS TODAY COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Nicola Contuzzi, Mariia Rashkovets, Giuseppe Casalino
Summary: This study investigates the effects of dwell time, down force, and rotational speed on microstructure, microhardness, and material flow during solid-state welding. Probeless friction stir spot welding (P-FSSW) was used to join AA2024, AA6082, and AA5754 aluminum plates of different thicknesses. The results show that down force significantly influences material flow and weld quality. High friction energy and intensive material flow promote the formation of vortexes, which enhance metals mixing and grain refinement.
SCIENCE AND TECHNOLOGY OF WELDING AND JOINING
(2023)
Article
Automation & Control Systems
Yu Guishen, Chen Xin, Wu Zitao, Zhang Guanchen, Chen Yixiong
Summary: Four types of probeless tools with different groove features were designed and their effect on the microstructure and mechanical properties of friction-stir-spot-welded aluminum alloy sheets was investigated. The results showed that tools with spiral features achieved higher tensile-shear failure load compared to the featureless tool.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2022)
Article
Engineering, Manufacturing
Jicheng Gao, Jiachen Dong, Sunyi Zhang, Liang Yu, Huiming Jin, Jianfeng Zhang, Yifu Shen
Summary: The study shows that adjusting the rotation speed and dwell time in friction stir spot welding can reduce defects, increase structure density, and achieve high-strength welding results, demonstrating a potential application prospect for high-temperature resistant engineering plastics.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART B-JOURNAL OF ENGINEERING MANUFACTURE
(2021)
Article
Engineering, Aerospace
Yuqing Mao, Ping Yang, Wenyan Zhang, Ning LI, Hao Nie, Danyang Lin, Liming Ke
Summary: In order to improve the tensile-shear properties of friction stir lap welded dissimilar Al/Mg joints, innovative pin-tip profiles were designed and welding speed was optimized. The effects of these factors on the formation, interface microstructure, and mechanical properties of the joints were investigated. It was found that increasing the welding speed initially increased and then decreased the tensile-shear load of the joints produced by three pins. The joints made by the T-pin at a welding speed of 75 mm/min exhibited the highest tensile-shear load and showed improved interface properties.
CHINESE JOURNAL OF AERONAUTICS
(2023)
Article
Nanoscience & Nanotechnology
Heedong Do, Saeed Asadi, Nokeun Park
Summary: The CoCrFeMnNi high entropy alloy was successfully joined to STS304 stainless steel using friction stir welding process. The joint exhibited superior cryogenic tensile properties compared with its properties at room temperature, thanks to significant martensitic transformation induced plasticity at LN2.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Automation & Control Systems
Yangfan Zou, Wenya Li, Qiang Chu, Zhikang Shen, Feifan Wang, Huawei Tang, Achilles Vairis, Liyuan Liu
Summary: AA2219 aluminium alloy plates with large thickness ratios were successfully produced using the RFSSW method, but joints showed issues such as insufficient refill and weak bonding, along with changes in microstructure and hardness distribution. Tensile-shear strength was closely related to defect morphology, with two different fracture modes observed in the specimens.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2021)
Article
Physics, Multidisciplinary
M. Bakkiyaraj, J. Ananth, V Sivamaran, P. K. Nagarajan
Summary: This article examines the properties of joints fabricated by friction welding (FW) using AA6061-T6 and AA7075 as examples of both similar and dissimilar metals. The effect of heat treatment after welding on the joint's metallurgical characteristics is also investigated. The findings demonstrate that the joint characteristics are enhanced by precipitate nucleation occurring in the joint interface under the heat treatment method of solutionizing heat treatment with synthetic ageing (STA). The tensile strength and microhardness of the joints made with both similar and dissimilar metals are influenced by the STA treatment in different ways.
Article
Construction & Building Technology
Yixun Wang, Seiichiro Tsutsumi, Takumi Kawakubo, Hidetoshi Fujii
Summary: This study evaluated the fatigue performance of weathering steels with high phosphorus content joined by friction stir welding (FSW), and studied the influence of weld defects on fatigue life. The results showed that the FSW joints of weathering steels had higher fatigue strength and flat S-N curves. Fatigue fracture near the weld nugget was mainly induced by weld defects.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Sufian Raja, Mohd Ridha Muhamad, Farazila Yusof, Mohd Fadzil Jamaludin, Tetsuo Suga, Huihong Liu, Yoshiaki Morisada, Hidetoshi Fujii
Summary: In this study, dissimilar joints between AZ61 magnesium alloy and mild steel were successfully produced using the friction stir alloying (FSA) procedure with Al-CNT additions. The influence of carbon nanotubes (CNT) weight percentages and welding speed on tensile strength and characteristics of the welding interface was investigated. The results showed that the tensile strength of the joint with 3% CNT improved up to 222 MPa.
SCIENCE AND TECHNOLOGY OF WELDING AND JOINING
(2022)
Article
Materials Science, Multidisciplinary
Mohamed Saleh, Huihong Liu, Kohsaku Ushioda, Hidetoshi Fujii
Summary: The effect of Zn interlayer on the microstructure and mechanical properties of dissimilar A1100 and SUS316L friction stir welded butt joints was investigated. It was found that Zn could improve the joint's tensile strength by forming a solid solution with A1100 matrix. The addition of Zn also inhibited the growth of Al-Fe IMCs, contributing to the obtained tensile strength.
SCIENCE AND TECHNOLOGY OF WELDING AND JOINING
(2022)
Article
Materials Science, Multidisciplinary
Yixun Wang, Seiichiro Tsutsumi, Takumi Kawakubo, Hidetoshi Fujii
Summary: The present study investigates the microstructures and mechanical properties of high phosphorus steels joined by friction stir welding. The results demonstrate that alloying elements contribute to the refinement of microstructures and improve the mechanical properties of the welded joints.
SCIENCE AND TECHNOLOGY OF WELDING AND JOINING
(2022)
Article
Materials Science, Multidisciplinary
Mun Sik Jeong, Tak Min Park, Dong-Il Kim, Hidetoshi Fujii, Hye Ji Im, Pyuck-Pa Choi, Seung-Joon Lee, Jeongho Han
Summary: This work demonstrated the viability of friction stir welding for the welding of medium-Mn steels when used as cryogenic vessel materials for liquefied gas storage. The friction stir welded steel exhibited improved microstructure and impact toughness compared to tungsten inert gas welding. The presence of gamma R phase and nanoscale globular microstructure in the weld zone contributed to the enhanced impact toughness at low temperatures.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2022)
Article
Nanoscience & Nanotechnology
Tomoya Nagira, Terumi Nakamura, Fumiyoshi Yoshinaka, Takahiro Sawaguchi, Yasuhiro Aoki, Masayoshi Kamai, Hidetoshi Fujii, Akihisa Takeuchi, Masayuki Uesugi
Summary: In this study, the dendrite-scale microstructural evolution of Fe-Mn-Si alloys during TIG spot welding was observed using high-spatial resolution X-ray imaging and diffraction. The solidification mode was found to significantly influence the susceptibility to solidification cracking.
SCRIPTA MATERIALIA
(2022)
Article
Materials Science, Multidisciplinary
Mohammad Ashraf bin Ariffin, Mohd Ridha bin Muhamad, Sufian Raja, Mohd Fadzil Jamaludin, Farazila Yusof, Tetsuo Suga, Huihong Liu, Yoshiaki Morisada, Hidetoshi Fujii
Summary: The joining between lightweight magnesium alloys and steel is challenging due to the immiscible properties between these metals. In this study, a new method called friction stir alloying (FSA) was proposed to solve this problem. By adding carbon nanotubes (CNT) and copper powder between the workpieces and performing friction stir welding (FSW) at different traverse speed and constant rotational speed, the researchers successfully achieved the joining of magnesium alloys and steel. The analysis of the microstructure and mechanical properties of the joints showed that the addition of CNT and copper significantly improved the mechanical performance of the joints.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Metallurgy & Metallurgical Engineering
Sho Matsui, Kohsaku Ushioda, Hidetoshi Fujii
Summary: Resistance spot welding is widely used in automobile assembly, but it results in a decrease in cross-tension strength (CTS) when high-strength steel sheets are used. Friction element welding (FEW) was explored as an alternative to improve CTS by joining high-strength steel sheets. However, even with FEW, the CTS still decreased at the joint when a high-carbon-content steel sheet was used as the lower sheet. This decrease in CTS was attributed to the low local ductility caused by the large hardness difference (.Hn) between martensite (M) and ferrite ( a) in the inter-critically annealed and quenched area during joining.
ISIJ INTERNATIONAL
(2023)
Article
Materials Science, Multidisciplinary
Meng-ran Zhou, Yu-feng Sun, Yoshiaki Morisada, Qing-yu Shi, Hidetoshi Fujii
Summary: This study systematically analyzed the mechanism of texture weakening in double-sided friction stir welded magnesium alloy. The results revealed that welding temperature and material flow mode simultaneously control the randomization of (0001) texture. The unique material flow at the mid-thickness layer caused by double-sided friction stir welding was identified as the dominant mechanism for texture randomization.
SCIENCE AND TECHNOLOGY OF WELDING AND JOINING
(2023)
Article
Materials Science, Multidisciplinary
Jeong-Won Choi, Weihao Li, Kohsaku Ushioda, Motomichi Yamamoto, Hidetoshi Fujii
Summary: This study investigated the effects of stacking fault energy (SFE), temperature, strain, and strain rate on microstructural evolution and dynamic recrystallization (DRX) mechanism during linear friction welding (LFW) of face-centered cubic materials, specifically Al alloys (AA1050 and AA5052). The results showed that the temperature played a crucial role in the microstructural evolution, with high temperatures leading to continuous DRX and low temperatures resulting in discontinuous DRX. The grain structure and texture evolution depended on various parameters, with strains and strain rates dominating at temperatures above 0.5Tm and the SFE influencing at temperatures below 0.5Tm. Additionally, the Zener-Hollomon parameters of the Al alloy joints were investigated, and it was found that the AA5052 joints had a larger grain diameter than the AA1050 joints at lower Z values, but a smaller grain diameter at higher Z values. These differences were attributed to the lower SFE of AA5052, which promoted DRX and grain refinement during LFW.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Metallurgy & Metallurgical Engineering
Hiroaki Tsuchiya, Kazumasa Hatsuda, Takumi Kawakubo, Kohsaku Ushioda, Hidetoshi Fujii, Masato Yamashita, Shinji Fujimoto
Summary: In this study, the structure and protectiveness of rust layers formed on friction stir welded high phosphorus carbon steels were examined and compared with those on SMA490AW and COR-TEN weathering steels. The results showed that the rust layers on high phosphorus carbon steels exhibited improved protectiveness compared to weathering steels, and friction stir welding did not deteriorate the corrosion resistance of high phosphorus carbon steels.
TETSU TO HAGANE-JOURNAL OF THE IRON AND STEEL INSTITUTE OF JAPAN
(2022)
Article
Metallurgy & Metallurgical Engineering
Zexi Wu, Tomoya Nagira, Kohsaku Ushioda, Goro Miyamoto, Hidetoshi Fujii
Summary: 0.2C-2Si steels containing 0-4% Cr were prepared and subjected to friction stir welding (FSW). The tensile properties of the stir zones were greatly enhanced by FSW, with the 0.2C-2Si-4Cr joint showing a high tensile strength of 1720 MPa and an excellent balance of ductility. This improvement is attributed to the refinement of microstructures and the formation of ausformed martensite induced by FSW.
TETSU TO HAGANE-JOURNAL OF THE IRON AND STEEL INSTITUTE OF JAPAN
(2022)
Article
Metallurgy & Metallurgical Engineering
Takayuki Yamashita, Kohsaku Ushioda, Hidetoshi Fujii
Summary: The study investigated the inhomogeneity in microstructures of a duplex stainless steel welded at different rotational speeds, analyzing the relationship with temperature gradient and dynamic recrystallization behavior. It was found that friction stir welding promoted the formation of new grains with different phases, and a linear relationship between the sizes of ferrite and austenite grains was observed in the layered structure.
TETSU TO HAGANE-JOURNAL OF THE IRON AND STEEL INSTITUTE OF JAPAN
(2022)
Article
Metallurgy & Metallurgical Engineering
Takumi Kawakubo, Kohsaku Ushioda, Hidetoshi Fujii, Takahiro Kamo, Tomoyuki Yokota
Summary: This study investigates the effects of carbon and phosphorus contents on the microstructure and mechanical properties of friction stir welded joints. It was found that higher welding temperature reduces phosphorus segregation and improves work hardening rate and upper shelf energy.
TETSU TO HAGANE-JOURNAL OF THE IRON AND STEEL INSTITUTE OF JAPAN
(2022)
Article
Metallurgy & Metallurgical Engineering
Noboru Konda, Tomotaka Kitamura, Masakazu Mori, Yasuhiro Aoki, Yoshiaki Morisada, Hidetoshi Fujii
Summary: In this study, linear friction welding (LFW) is used to join high carbon steel, and the effect of LFW conditions on the toughness and absorbed energy of the joints is investigated. The results indicate that the microstructure and hardness of the joints change with increasing applied pressure, which affects the maximum absorbed energy.
TETSU TO HAGANE-JOURNAL OF THE IRON AND STEEL INSTITUTE OF JAPAN
(2022)
