Article
Engineering, Manufacturing
H. Peng, D. L. Chen, S. F. Guo, H. Hong, K. H. Zheng, X. F. Bai, D. Y. Li, X. Q. Jiang
Summary: The present study investigated the microstructural changes at the Mg/Zn and Al/Zn interfaces of ultrasonic spot welded joints between a rare-earth containing ZEK100 magnesium alloy and an AA6022 aluminum alloy with a zinc interlayer. It was found that diffusion or reaction occurred at both interfaces, with faster reaction at the Mg/Zn interface due to higher Zn diffusion rate in Mg and lower eutectic temperature. Increasing welding energy led to thicker diffusion layer at both interfaces, but the layer at Al/Zn interface was thinner than that at Mg/Zn interface. Joining mechanisms involved mechanical interlocking and metallurgical bonding facilitated by grain refinement during ultrasonic spot welding. The peak tensile lap shear strength occurred at a welding energy of 1000 J, with failure at the diffusion layer of the Mg/Zn interface.
JOURNAL OF MANUFACTURING PROCESSES
(2023)
Article
Automation & Control Systems
Soumya Sobhan Dash, Mudit Kesharwani, Abdulmohsen Albedah, Xianquan Jiang, Dongyang Li, Daolun Chen
Summary: The study aimed to investigate the feasibility of joining ZEK100-O magnesium alloy to AA7072-clad high-strength AA7075-T6 aluminum alloy using solid-state ultrasonic spot welding (USW). The interfacial microstructures, tensile lap shear strength, and fatigue resistance were evaluated. Mechanical interlocks and a diffusion layer were observed at the weld interface, resulting in enhanced tensile lap shear strength and fatigue life.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Chuan Xu, Xinjian Yuan
Summary: High frequency ultrasonic vibration was used for arc welding of MB3 Mg alloy to improve welding defects and microstructure issues. By optimizing experimental parameters, Mg alloy joints with favorable mechanical properties were obtained. However, excessive ultrasonic power could degrade tensile strength.
Article
Materials Science, Multidisciplinary
Fangzhou Yang, Bing Liu
Summary: The study analyzed the effects of ultrasonic vibration on the microstructure and mechanical properties of AZ31 Mg alloy welded joints. It was found that under optimized ultrasonic power of 1.0 kW, the welded joint achieved a maximum tensile strength of 256 MPa with a fracture surface showing plastic fracture characteristics.
MATERIALS RESEARCH EXPRESS
(2021)
Article
Materials Science, Multidisciplinary
M. Paidar, S. Memon, V. Olegovich Samusenkov, B. Babaei, O. O. Ojo
Summary: Changing the shoulder geometry in friction spot extrusion welding-brazing can increase the tensile/shear strength of the joint, attributed to the larger brazed zone and complete filling of the pre-threaded hole.
Article
Materials Science, Multidisciplinary
Dewang Zhao, Chao Jiang, Kunmin Zhao
Summary: Magnesium alloy, copper and other light alloys are widely used in various fields due to their excellent mechanical properties, but connecting light alloys has always been a challenge. This study conducted ultrasonic welding experiments between AZ31B magnesium and pure copper, studying the fracture, microstructure, tensile properties, and connection mechanism of the joint. A finite element analysis model of the magnesium-copper ultrasonic welding process was established. The ultrasonic connection between magnesium alloy and copper is mainly achieved through the interface diffusion layer formed during the welding process. The maximum joint strength reached 3798 N.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
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
Engineering, Manufacturing
Tanmay, Sudhanshu Sekhar Panda
Summary: In this study, pure copper and aluminum alloy were lap joined using conventional TIG welding, and a successful weld was achieved. Metallurgical properties of the joints were investigated using various methods, with IMCs layers of different thickness formed at different welding parameters. The mechanical properties were tested through tensile shear tests, revealing a comparable load-carrying capacity to other non-conventional welding processes.
CIRP JOURNAL OF MANUFACTURING SCIENCE AND TECHNOLOGY
(2021)
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, Characterization & Testing
Chakkaravarthi Rajarajan, Paramasivam Sivaraj, Tushar Sonar, Selvaraj Raja, Nallusamy Mathiazhagan
Summary: This research investigates the formation, microstructure, and strength performance of DP 800 steel joints in resistance spot welding (RSW) for automotive applications. The study found that welding current has a significant influence on nugget formation. RSW joints made using a welding current of 5.5 kA, an electrode pressure of 4.0 MPa, and a welding time of 2.0 s showed defect-free weld nugget, higher tensile shear strength, and microhardness, meeting the requirement for automotive applications.
Article
Materials Science, Characterization & Testing
Kazufumi Nomura, Soshi Deno, Taketo Matsuida, Satoshi Otaki, Satoru Asai
Summary: Understanding the joining process in real time during welding can improve welding quality, reliability, and manufacturing process efficiency. This study experimentally investigated the in-process ultrasonic behavior using a laser ultrasonic method, and examined the measurement and characteristics of melting behavior during welding.
NDT & E INTERNATIONAL
(2022)
Article
Materials Science, Multidisciplinary
Jiansheng Li, Zuyuan Xu, Yu Zhao, Wei Jiang, Wenbo Qin, Qingzhong Mao, Yong Wei, Banglun Wang
Summary: A copper/Q235 steel/copper composite block with excellent bonding interfaces was successfully prepared by explosive welding. The microstructure and mechanical properties of the interfaces were investigated and it was found that the shear strength of the upper and lower interfaces was higher than 235 MPa and 222 MPa, respectively. The failure of the specimens occurred within the copper and not at the bonding interface, which was attributed to the absence of cavities and cracks at the interface and the presence of a metallurgical bonding with ultra-fine grains.
Article
Materials Science, Multidisciplinary
Mikko Hietala, Mohammed Ali, Ali Khosravifard, Markku Keskitalo, Antti Jarvenpaa, Atef Hamada
Summary: The tensile-shear strength of laser-welded lap joints in abrasion resistance ultra-high strength ARS-600 steel was optimized through evaluation of joints achieved with different welding parameters and configurations. The microstructural evolution of the fusion zone was characterized using electron backscatter diffraction (EBSD), and stress analysis of different weld patterns was conducted using finite element method (FEM).
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2021)
Article
Nanoscience & Nanotechnology
Haining Yao, Hongyuan Wen, Ke Chen, Muyang Jiang, Kolan Madhav Reddy, Katsuyoshi Kondoh, Min Wang, Xueming Hua, Aidang Shan
Summary: The study focused on the formation of intermetallic compounds at the joint interface between dissimilar metals. FeCoCrNiMn high entropy alloy was joined to traditional 1060Al alloy by friction stir lap welding, revealing a continuous interfacial layer with varying thickness and three different types of interfacial structures.
SCRIPTA MATERIALIA
(2021)
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
Nanoscience & Nanotechnology
H. Wang, D. T. Zhang, C. Qiu, W. W. Zhang, D. L. Chen
Summary: A low-alloyed Mg-1.2Zn-0.1Ca alloy was successfully extruded at low temperatures. The extruded alloy at 150°C exhibited a high yield strength and good elongation, comparable to high-alloyed AZ91 and Mg-RE alloys.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Nanoscience & Nanotechnology
S. S. Dash, D. J. Li, X. Q. Zeng, D. Y. Li, D. L. Chen
Summary: In this study, the micro-deformation mechanisms in an Al-Si cast alloy under stepwise compressive loading were investigated using EBSD and slip trace analyses. The presence of heterogeneous microstructural features significantly influenced the slip trace characteristics. Four types of slip traces in primary α-Al grains were identified, revealing the nature of dislocation motion and the extent of deformation difficulty associated with grain orientations and eutectic Si particles. Crystallographic factors were analyzed to understand the deformation behavior of the alloy.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Nanoscience & Nanotechnology
S. S. Dash, D. J. Li, X. Q. Zeng, D. Y. Li, D. L. Chen
Summary: The aim of this study is to investigate the monotonic and cyclic deformation behavior of a high-pressure die cast Silafont (R)-36 alloy in a naturally-aged T4 state. The T4 heat treatment led to significant microstructural changes, resulting in the transformation of coralloid-like eutectic Si particles to spheroidal Si particles embedded in the Al matrix. The T4 alloy exhibited strong cyclic hardening and a longer low cycle fatigue life compared to its as-cast state at lower strain amplitudes, attributed to particle-dislocation interactions during deformation. A strain energy density-based model incorporating microstructural aspects can be used to predict the fatigue life of the T4 alloy.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Materials Science, Ceramics
C. C. Ye, H. Q. Ru, D. L. Chen
Summary: This study aimed to investigate the effects of sintering additives on the fatigue life of silicon nitride (Si3N4) ceramics sintered via hot pressing, focusing on the prominent toughening mechanisms. The fatigue life and probability of survival of YMH samples using MgO and Y2O3 as sintering additives were found to be higher than those of YAH samples using Al2O3 and Y2O3 as sintering additives. This was attributed to the higher aspect ratio of the elongated β-Si3N4 grains, larger compressive residual stresses, and the presence of only amorphous (or glassy) phase at β-Si3N4 grain boundaries in the YMH sample.
CERAMICS INTERNATIONAL
(2023)
Article
Engineering, Mechanical
Aakash Kumar, Yunqing Tang, D. Y. Li, D. L. Chen, Wei Li, Q. Y. Li
Summary: Solid-solution hardening can improve the wear resistance of metals by pinning dislocations and affecting the atomic bond strength and Young's modulus. Cu was hardened by Ni and Mn, resulting in increased hardness and Young's modulus with Ni addition, and decreased Young's modulus but increased hardness with Mn addition. However, the effect of Ni and Mn on wear resistance is underestimated or overestimated by using the classic Archard equation, which can be corrected by a wearing energy model taking into account the influence of Young's modulus.
Article
Engineering, Mechanical
Y. Q. Tang, A. Kumar, D. L. Chen, D. Y. Li, Q. Y. Li, W. Li
Summary: The Bauschinger effect, which refers to the decrease in yield strength of a metal after plastic deformation in the opposite direction prior to testing, affects the wear resistance of materials under different conditions. This study investigated the influence of the Bauschinger effect on the wear resistance of strain-hardened Cu (FCC) and Mg (HCP) through experiments and molecular dynamics simulations. It was observed that strain-free Cu exhibited a stronger Bauschinger effect, while the situation was reversed for undeformed and deformed Mg samples. The underlying mechanisms were studied through molecular dynamics simulations, revealing that high-density dislocations weaken the Bauschinger effect in cold-worked Cu, while cold-worked Mg with fewer defects has more space for defect generation and cancellation, resulting in a stronger Bauschinger effect. Additionally, the Bauschinger effect was found at the oxide/metal interface, making the oxide scale on worn surfaces less prone to being scratched off during bi-directional sliding, thus enhancing the wear resistance of the metal.
Article
Materials Science, Multidisciplinary
Mingyu Wu, Guijiang Diao, Zhen Xu, Ruiken Sim, Wengang Chen, Daolun Chen, Dongyang Li
Summary: Microstructure, mechanical properties, wear resistance, corrosion and corrosive wear resistance of AlCrFeNiWx (x = 0, 0.1, 0.2, 0.3 and 0.4) medium-entropy alloys (MEAs) prepared by vacuum arc melting process were investigated. Tungsten addition in AlCrFeNi alloy significantly improves its hardness, strength, pitting resistance and passivation property, while excessive W addition reduces ductility. AlCrFeNiW0.3 shows the highest corrosion resistance and W enhances the wear and corrosive wear resistance in AlCrFeNiW0.4.
Review
Materials Science, Multidisciplinary
Soumya Sobhan Dash, Daolun Chen
Summary: This review focuses on recent developments in the processing, structure, and mechanical properties of structural Al-Si alloys, aiming to address pressing environmental issues and achieve lightweighting strategies. It summarizes advancements in casting methods and additive manufacturing processes, analyzes improvements in thermal stability, electrical conductivity, and mechanical strength, and discusses fatigue failure mechanisms and surface topography.
Review
Materials Science, Multidisciplinary
Dhruv Bajaj, Aihan Feng, Shoujiang Qu, Zhuo Chen, Dongyang Li, Daolun L. Chen
Summary: The 3D printing of high-entropy alloys (HEAs) offers greater flexibility in designing and manufacturing novel materials. These 3D-printed HEAs exhibit unique microstructures and mechanical properties, breaking the limitations of conventionally-manufactured materials. This review provides insight into the deformation behavior of 3D-printed HEAs, with emphasis on fatigue characteristics and the effects of postfabrication thermomechanical processing.
ADVANCED ENGINEERING MATERIALS
(2023)
Article
Automation & Control Systems
Soumya Sobhan Dash, Mudit Kesharwani, Abdulmohsen Albedah, Xianquan Jiang, Dongyang Li, Daolun Chen
Summary: The study aimed to investigate the feasibility of joining ZEK100-O magnesium alloy to AA7072-clad high-strength AA7075-T6 aluminum alloy using solid-state ultrasonic spot welding (USW). The interfacial microstructures, tensile lap shear strength, and fatigue resistance were evaluated. Mechanical interlocks and a diffusion layer were observed at the weld interface, resulting in enhanced tensile lap shear strength and fatigue life.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
H. Wang, D. T. Zhang, C. Qiu, W. W. Zhang, D. L. Chen
Summary: A low-alloyed Mg-1.2Zn-0.1Ca alloy was fabricated via low-temperature extrusion and annealing to attain heterostructures with different fine-grained fractions, showing significant effects on the mechanical properties. The alloy exhibited increased fine-grained fraction and fine grain size with annealing, resulting in superior mechanical properties of high yield strength and good ductility. Hetero-deformation induced strengthening plays a key role in achieving the superior mechanical properties.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
X. R. Guan, Q. Chen, S. J. Qu, G. J. Cao, H. Wang, A. H. Feng, D. L. Chen
Summary: Increasingly harsh service conditions require better high strain-rate performance of titanium alloys. Adiabatic shear band (ASB), which is prone to dynamic loading, often leads to catastrophic damage. However, the relationship between internal nanostructures and shear instability remains unclear.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Nanoscience & Nanotechnology
G. J. Diao, A. Q. He, Y. Q. Tang, M. Y. Wu, D. Zhang, W. G. Chen, D. L. Chen, D. Y. Lia
Summary: The individual effects of Al and Ti on microstructure, mechanical and tribological properties of CrFe2Ni2 alloy were investigated. Al addition changed the alloy phase from FCC to a mixture of FCC, A2 and B2 phases, increasing the mechanical strength while slightly sacrificing ductility. Ti caused the formation of hard phases in the alloy, increasing the wear resistance, but also decreasing the ductility. Detailed characterization is crucial for optimizing tribological applications of relevant HEAs.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Engineering, Mechanical
S. E. Mousavi, A. Q. He, M. Palimi, D. L. Chen, D. Y. Li
Summary: The individual influences of Al, Fe and Ni on the microstructure, wear resistance and mechanical properties of high-entropy alloys (AlxCrFeyNizTi0.2) were studied. It was found that increasing Al content led to the replacement of the FCC phase by disordered and ordered BCC phases, resulting in increased micro-hardness and decreased wear volume loss. Fe increased the fraction of A2 phase but reduced hardness and wear resistance. Ni helped form a FCC phase, which decreased hardness and increased wear volume loss. Among all specimens, AlCrFeNiTi0.2 and Al0.5CrNiTi0.2 showed the highest wear resistance.
Article
Materials Science, Multidisciplinary
Zhiying Liu, Lizhong Lang, S. M. A. K. Mohammed, Daolun Chen, Bei He, Yu Zou
Summary: Nanoindentation is widely used for measuring local mechanical properties of heterogeneous materials. In this study, a nanoindentation mapping method with small indentation depths (<200 nm) is used to investigate the nanohardness (H) of the alpha phase in an additively manufactured titanium alloy. The results reveal two groups of H values exhibited by alpha grains with different crystal orientations, in contrast to the wide range of H values measured by conventional large-depth nanoindentation. These two groups of H values are attributed to the contribution of elasticity in the measurement using small-depth nanoindentation. Additionally, the H values are correlated with the microscopic mechanical behavior of alpha grains, showing that hard alpha grains are deformed by shear banding while soft alpha grains are deformed by dislocation slip.
