A Study on Structure and Tensile Properties of Copper Clad Aluminum Composite Bus-Bar Prepared through Isothermal Fabrication

摘要

By utilizing isothermal technology to fabricate copper clad aluminum composite ("CCAC") bus-bar for electric power transmission and electrical application purpose, of which the bimetallic interface possesses the properties of low transitional electrical and thermal resistance, strong bonding strength, and good ductility and formability. The CCAC Bus-bar, structured as three layers of cladding layer, core layer and interfacial bonding layer, is produced through the patented isothermal processing which undergoes interfacial transition region deformation and atomic diffusion in a thermo field to achieve bimetallic metallurgical bonding. The produced CCAC bus-bar is specified the copper volume ratio of 15%～30%, mass ratio of 35%～60%, interfacial shear strength ranged 120MPa～230MPa, elongation 25%～40%. For the 20% of copper volume ratio, the DC resistivity is 0.0248 Ω·m, the current-carrying-capacity is equivalent to 86% of copper bus, density of 3.94g/cm~3. Using of Scanning Electron Microscope (SEM) to study the microstructure of the interfacial transition region, Energy Disperse Spectroscope (EDS) to analyze the trend of Cu-Al atomic interdiffusion and composition in the interfacial transition region, X-ray Diffraction (XRD) to inspect whether Cu-Al intermediate compounds exist in the interfacial transition region. The mechanical experiment reveals the interfacial bonding shear strength is greater than aluminum intrinsic anti-shear strength. The unique layered CCAC makes the anti-vibration fatigue strength much higher than copper and possesses many excellent physical and mechanical properties beyond the single metal, is an excellent overall performance material. Beyond its superior lightweight, low electrical and thermal resistance, anti-blast, bearing pressure, high tensile and bonding strength, appropriate elongation, CCAC highlights the importance in electric and thermal conductivity, refrigeration, aeronautics, aerospace, defense and various industrial applications.