Study On Control Of Interface Shape In Copper-Aluminum Composite Strip

Composite material is made from two or more different materials by physical or chemical means, which compose a material with new macroscopic properties. In recent years, people have asked the performance and stability requirements to increase, which requires precise control of layer thickness and its thickness ratio. The rolling process of0.12mm-thicked copper-aluminum-copper composite strip that involved in this article has matured. but for the subsequent heat treatment process has not yet quantitative research. To obtain high-quality composite strip, it must inhibit the formation of compounds at high temperature, and improve the bonding strength.This paper will make a systematic study on the metal compounds at high temperatures, and explore a certain method to inhibit the formation of compounds. Firstly, we should make a lot of annealing experiments in the box-type resistance furnace, and analysis the morphology, tensile properties of the annealed composite, next obtain the best heat treatment process parameters; Secondly, we make the annealing experiments in in a vacuum furnace, and measure the shear strength in different magnetic field, and analysis the interface morphology; Lastly, explain the inhibition theory of the generation of complex compounds, Specific findings are as follows:(1) Annealed the composite strip in the box-type resistance furnace at different temperatures:with the bigger of annealing temperature or holding time, the thickness of composite compounds get wider, the strength get more decrease and plasticity get more increase. The best heat treatment process parameters is the annealing temperature410℃, holding time10minutes.(2) Annealed the composite strip in the vacuum furnace in different magnetic field intensity temperatures:with the bigger of annealing temperature or holding time, the thickness of composite compounds get wider; the strength get more decrease with the bigger of annealing temperature.(3) Applied to0.1T,0.05T magnetic field, the thickness of the interface compounds get narrower in300℃than no magnetic field, the interface shear strength up to124Mpa; this phenomena is not in other magnetic fields, Two kinds of annealing mode have generated CuAl, CuAl2, Cu9Al4.(4) The reason that magnetic field can promote or inhibit the spread of the interface is due to different magnetism of copper and aluminium. Copper is anti-magnetic materials, the diffusion activation energy increases when applied magnetic field; while, the aluminium is opposite, the diffusion activation energy decreased. The change of diffusion activation energy transform the thickness of diffusion layer.