Browse Topic: Copper
Led by Dr. Marina Freitag, a research group from the School of Natural and Environmental Sciences created dye-sensitized photovoltaic cells based on a copper (II/I) electrolyte, achieving an unprecedented power conversion efficiency of 38 percent and 1.0V open-circuit voltage at 1,000 lux (fluorescent lamp). The cells are non-toxic and environmentally friendly — setting a new standard for sustainable energy sources in ambient environments.
The demand for lightweight, high-efficiency components in electric vehicles (EVs) highlights the critical need for reliable Al-Cu joints with superior electrical and thermal conductivity. While diffusion bonding has emerged as a promising approach, interfacial impurities and voids often degrade joint quality and conductivity. Conventional manual polishing was initially employed to prepare Cu and Al surfaces; however, this method proved insufficient in consistently removing oxides and contaminants, leading to non-uniform bonding. In addition, the larger surface area of the samples made traditional polishing impractical, further motivating the use of electropolishing. To overcome these limitations, we introduce electropolishing pretreatment to achieve cleaner, void-free interfaces. Electropolishing effectively dissolves surface asperities and contaminants, enabling intimate atomic contact during bonding and minimizing the formation of brittle intermetallic phases. A systematic investigation of bonding parameters was conducted using a custom-designed graphite clamping system. Microstructural analyses reveal that advanced polishing plays a pivotal role in producing uniform, impurity-free interfaces, resulting in reduced intermetallic thickness, improved bonding strength, and enhanced current-carrying capability. This study demonstrates the clear advantages of electropolishing over conventional polishing and establishes a scalable pathway to manufacture high-performance conductive joints for next-generation EV motor and power distribution systems.
Reliable monitoring of the internal state of lithium-ion batteries (LIBs) is crucial for mitigating potential safety hazards. The incorporation of a reference electrode (RE) within the battery constitutes a vital approach for achieving single-electrode monitoring and understanding changes in electrode state during cycling. Among these, the lithium-copper reference electrode (Li-Cu RE) is particularly cost-effective and straightforward to prepare, being fabricated by depositing lithium onto a copper wire. However, Li-Cu RE exhibits a relatively short effective lifespan during long-term cycling, thereby limiting its practical application. In this work, based on a self-fabricated three-electrode single-layer pouch cell, the microstructural changes before and after failure of the Li-Cu RE were characterized and analyzed, revealing its failure evolution process. Post-failure microstructures observations exhibit marked porosity in the electrode, attributed to substantial depletion of surface lithium metal. Concurrently, the copper wire's elevated potential dominantly influences the overall Li-Cu RE potential, causing its potential to rise and destabilize. This induces a sharp decline in the measured electrode's potential curve. Furthermore, comparative analysis of key factors influencing Li-Cu RE lifespan were investigated. In the static state, the theoretical failure time of Li-Cu RE differed by only approximately 9 hours from that in the cycling state. Crucially, isolating the test electrode from the Li-Cu RE nearly doubled its lifespan, revealing that current generated by the potential difference between the test electrode and Li-Cu RE is the primary cause of failure under low-rate cycling. This paper systematically elucidates the observed failure behavior of the Li-Cu RE and comprehensively analyzes the various factors, which aids in further understanding the failure mechanism of the Li-Cu RE and identifying targeted solutions.
The Korea Institute of Energy Research (KIER) has successfully developed ultra-lightweight flexible perovskite/ CIGS (copper indium gallium selenide) tandem solar cells and achieved a power conversion efficiency of 23.64 percent, which is the world’s highest efficiency for flexible perovskite/CIGS tandem solar cells reported to date. The solar cells developed by the research team are extremely lightweight and can be attached to curved surfaces, making it a promising candidate for future applications in buildings, vehicles, aircraft, and more.
U.S. Army researchers, in collaboration with academic partners, invented a stronger copper that could help advance defense, energy and aerospace industries thanks to its ability to endure unprecedented temperature and pressure extremes. Extreme materials experts at the U.S. Army Combat Capabilities Development Command (DEVCOM) Army Research Laboratory built on a decade of scientific success to develop a new way to create alloys that enable Army-relevant properties that were previously unachievable. An alloy is a combination of a metal with other metals or nonmetals.
Army and academic researchers have created stronger, more durable copper that could advance military systems. U.S. Army Combat Capabilities Development Command, Army Research Laboratory, Adelphi, MD U.S. Army researchers, in collaboration with academic partners, invented a stronger copper that could help advance defense, energy and aerospace industries thanks to its ability to endure unprecedented temperature and pressure extremes. Extreme materials experts at the U.S. Army Combat Capabilities Development Command (DEVCOM) Army Research Laboratory built on a decade of scientific success to develop a new way to create alloys that enable Army-relevant properties that were previously unachievable. An alloy is a combination of a metal with other metals or nonmetals. Along with researchers at Arizona State University, Lehigh University and Louisiana State University, ARL produced a nanocrystalline copper-tantalum-lithium alloy that can conduct electricity and heat like copper while demonstrating incredible strength and durability even at extremely high temperatures. Copper on its own has excellent heat and electricity conduction but doesn't do well under extreme conditions needed in operational environments.
With performance advances proposed for the Future Vertical Lift suite of aircraft and advancements in the electronic battlefield, it is imperative that advanced materials and concepts be included in the vehicle designs to meet the aggressive weight reduction objectives, structural requirements, and operational environment capabilities. Integrating electromagnetic (EM) shielding during the design process offers an opportunity to make progress towards the performance goals. To this end, efforts must be made to minimize the impact of this shielding to platform weight and structural performance. This article presents work to develop a hybrid multifunctional composite material technology that incorporates copper mesh into a carbon fiber and thermoplastic matrix structural composite material to achieve required levels of EM shielding and high levels of structural efficiency while reducing the overall weight of the system. This article focuses on the design of a representative helicopter tailcone as means of illustrating expected improvements in weight and manufacturing cost. Baselines that include structure fabricated from aluminum and thermoset composite are established and predicted improvements quantified.
A novel sintering method of bridging the two mechanically polished and oriented single-crystals together face-to-face in a non- environmental controlled atmosphere to fabricate the bicrystal substrate of NaCl of macroscopic thickness, with a common zone axis and having planarity over large areas, has been developed. Epitaxial [001] bicrystalline thin face-centered cubic (fcc) metal film of surface-reactive metal-containing tilt grain boundary across the interface is first grown in high vacuum directly by flash deposition on initially fabricated [001] oriented bicrystalline substrate of NaCl. The [001] tilt boundary, thus produced, and is examined by electron microscopy to characterize grain boundary morphology and structure. The findings of some preliminary investigations are then presented. A distinct atomic structure is observed for 310 and 210 inclination. Both HAADF-STEM and Diffraction images reveal that such fabricated high-angle grain boundary accommodates minor deviations from the exact high coincidence density ∑=5 misorientation. The potential use of the present technique is extended to produce a wide variety of homophase bicrystals, containing grain boundaries at the midplane, normal to any crystallographic surface without the necessity of a separate bonding operation.
The foundation specification (AMS3050) and this category specification (AMS3050/1) cover anti-seize greases conforming to the requirements but using the anti-seize ingredient Copper only.
This paper experimentally investigates direct effects of lightning strikes on flax fiber-reinforced polymers. Highcurrent artificial lightning strikes are conducted on coupon level to evaluate thermo-mechanical damage and to quantify the sufficiency of copper wire mesh as lightning strike protection (LSP). The dataset shall also serve for verification of prospected numerical simulation. The natural fiber flax, as a sustainable source of composite reinforcement, has been demonstrated to be suitable for semi-structural parts of rotorcraft. However, its low electrical and thermal conductivity requires a functional LSP layer for aviation applications. The test panels are investigated regarding their material combination, stacking sequence and level of LSP. Results show that two as well as three layers of 72 g/m2 copper mesh are not sufficient to withstand the standardized lightning current component A waveform of 200 kA. The high induced currents and low capability of energy dissipation leads to electro-explosion of metal and transient mechanical forces from shock waves causing mechanical damage on the test panels. Back surface-velocities increase with higher peak currents and higher level of protection results in lower damage. It is shown that a stacking of copper wire mesh results in less arc root dispersion.
A University of Bristol-led study, published in The Proceedings of the National Academy of Sciences, demonstrates how to make conductive, biodegradable wires from designed proteins. These could be compatible with conventional electronic components made from copper or iron, as well as the biological machinery responsible for generating energy in all living organisms.
The microstructure of the alloy and the manner in which it responds to heat treatment has been investigated. The alloy was aged at 550OC when it was initially spray-formed, or when its thickness was decreased by 38%. Before further aging of some specimens, a four-hour solution treatment at 1015OC was performed. The subsequent phase was a cold deformation that was barely 60% of the sample's initial thickness. The alloys' electrical conductivity and hardness may be evaluated based on how long they had been created. Following solution treatment and cold rolling, the alloy's peak hardness was around 380 kgf/mm2. In samples aged immediately under spray-produced conditions, the maximum peak hardness of 255 kgf/mm2 was attained. Conductivities in freshly cold-rolled samples could reach up to 75% of the standard for annealed copper internationally. It looks at the microstructural features of this alloy in this context, paying close attention to how various processing conditions affect them.
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