This work presents a new technique to generate uniform and micron-sized metal powders for advanced additive manufacturing. By collecting discrete chips resulting from ultrasonic vibration machining, we demonstrate the...
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With environmental protection and performance considerations, traditional chip interconnection materials fail to meet the harsh working requirements of power electronic devices. Copper and silver are widely used in po...
With environmental protection and performance considerations, traditional chip interconnection materials fail to meet the harsh working requirements of power electronic devices. Copper and silver are widely used in power electronics and other fields due to its good properties. Cu@Ag core-shell material own the advantages of Cu and Ag, and prevent their electrochemical migration issues. In this study, Cu@Ag composite preforms were prepared by electromagnetic compaction, and studied the electrochemical migration behaviors of Cu@Ag composite solder preforms using water-drop tests. Specifically, irregularly shaped Cu@Ag core shell powders and composite solder preforms were prepared, and microstructure was characterized using scanning electron microscopy (SEM). Nano silver pastes were used as a control sample, constant voltages of 5 V and 10 V were applied using an electrochemical workstation (CS 2350) to test the current curves of the circuit with time. Then, the electrochemical resistance of the Cu@Ag composite preforms was evaluated by analyzing the circuit short-circuit time. It showed that the electrochemical migration resistance of Cu@Ag solder joints was significantly better than nano-Ag sintered joints at 5 V. The voltage rised to 10V, the Cu@Ag solder joints did not fail until the 980s. Finally, we analyzed the electrochemical migration mechanism of Cu@Ag composite preforms.
Coupling electrochemical CO_(2)reduction(CO_(2)R)with a renewable energy source to create high‐value fuels and chemicals is a promising strategy in moving toward a sustainable global energy ***_(2)R liquid products,s...
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Coupling electrochemical CO_(2)reduction(CO_(2)R)with a renewable energy source to create high‐value fuels and chemicals is a promising strategy in moving toward a sustainable global energy ***_(2)R liquid products,such as formate,acetate,ethanol,and propanol,offer high volumetric energy density and are more easily stored and transported than their gaseous ***,a significant amount(~30%)of liquid products from electrochemical CO_(2)R in a flow cell reactor cross the ion exchange membrane,leading to the substantial loss of system‐level Faradaic *** severe crossover of the liquid product has—until now—received limited ***,we review promising methods to suppress liquid product crossover,including the use of bipolar membranes,solid‐state electrolytes,and cation‐exchange membranes‐based acidic CO_(2)R *** then outline the re-maining challenges and future prospects for the production of concentrated liquid products from CO_(2).
Acoustic emission (AE) technology is adopted to monitoring the whole corrosion fatigue behavior of AZ31 welded joints in 3.5 wt.% NaCl solution. Characteristics of AE signals, effect of corrosive environment and corro...
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Nanostructured semiconductor materials exhibit remarkable thermal insulating properties compared to their bulk counterparts, making them highly promising for Thermo-Electric (TE) applications. This study employs compu...
Nanostructured semiconductor materials exhibit remarkable thermal insulating properties compared to their bulk counterparts, making them highly promising for Thermo-Electric (TE) applications. This study employs computational tools to investigate the superior thermal insulating properties of Nanowire Chain (NWC) structures achieved through constriction engineering of laterally aligned nanowire arrays. Various surface and constriction modifications of NWCs are investigated to understand their impact on the thermal conductivity. The results demonstrate that the NWC structure achieves a substantial oneorder reduction in thermal conductivity compared to nanowires and nanosheets of similar dimensions. Moreover, this study evaluates the effectiveness of commonly used phonon suppression techniques, such as superlattice structures, shell alloying, and surface atom removal, in NWC configurations. The comprehensive analysis provides valuable insights into the phonon transport characteristics within different classes of NWCs, shedding light on their potential for diverse applications in the field of TE materials and thermal insulators.
Low-temperature solder material has been proposed as a solution in reducing the reflow temperature in order to solve the warpage issue in the advanced electronic packaging. Currently, Sn-Bi solder system is considered...
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Low-temperature solder material has been proposed as a solution in reducing the reflow temperature in order to solve the warpage issue in the advanced electronic packaging. Currently, Sn-Bi solder system is considered as a promising material system for low-temperature solder. Nevertheless, (Bi) phase coarsening after thermal aging causes the brittleness of the solder and thus decreases the reliability in real application. Element doping to Sn-Bi solder is typically used in tailoring its properties. However, tailoring properties in the multi-component system with experimental trial-and-error method is not economically feasible. This study employed machine learning approach to explore tensile properties of low-temperature solders.
Using the Boltzmann transport equation (BTE), we study the evolution of nonequilibrium carrier distributions in simple (sp) metals, assumed to have been instantaneously excited by an ultrafast laser pulse with photon ...
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MXene are a new class of materials that have gained great attention due to their potential as multifunctional materials for a variety of advanced technological applications. The density functional theory was utilized ...
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Ceramic On-Demand Extrusion (CODE) is an extrusion-based additive manufacturing process to produce highly dense sintered ceramic components from aqueous pastes with low binder content. This study examines the effects ...
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Because imitation learning relies on human demonstrations in hard-to-simulate settings, the inclusion of force control in this method has resulted in a shortage of training data, even with a simple change in speed. Al...
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