Oxidation Of Cu-Al Alloys

Copper which have fine electric conductivity and heat conductivity is a major metallic material in the life and production. Because of developing of science and technology recently, especially in modern industry, copper have wide application, the environmental requirements of copper demand highly in the space industry and electronic industry. In the space industry, copper can be made main parts for the man-made satellite and manned spacecraft. When these aircrafts return to ground, they would rub against the atmospheric air. In the integrated circuit field, copper have high-melting-point and conducts electricity well, therefore copper is a main material for the inside connection. However, the IC are packaged with 400oC, there would involve the oxidation of copper. As everyone knows the oxidizing material of copper do not have production like as Al2O3. So the copper can be constantly oxidized, thus reducing the useful life and combating waste.In view of the improving the copper of resistance to oxidation, there are many people making research in the early 20th century, but gaining the different results. Someone considers that adding some alloying element and through heat treatment to improve the pure copper,s resistance to oxidation. In many alloying elements, because Aluminium has higher reserve in the natural and low cost, aluminium is pitch on. Many studies show that copper,s resistance to oxidation would be enhancing with adding to Aluminium. As Cu and Al have different surface energy, the aluminium of the copper-aluminium alloy would segregation from inner to surface. Though there are some O2 which the partial pressure is low in the annealing atmosphere, the aluminium from the alloy can react with these oxygen. It results to form the protective oxide film Al2O3. The oxide film prevents copper to oxidizing, thus improving the copper of resistance to oxidation.This paper studied the oxidation behaviors of Cu0.2Al,Cu0.5Al,Cu1.0Al and Cu2.0Al alloys at high temperature by annealing in H2 or Ar atmosphere. the following research work was conducted in this doctoral dissertation and the resultant conclusions are presented as the following:SIMS depth profiles and surface morphologies and distribution and TEM of Cu0.2Al,Cu0.5Al,Cu1.0Al and Cu2.0Al alloys at 600℃by annealing in H2 atmosphere for 1440min and at 0.6℃/min coolingrate to room temperture were analyzed. the oxidation kinetics of Cu0.2Al,Cu0.5Al,Cu1.0Al and Cu2.0Al alloys and 6N Cu under 1 atm O2 at 600℃,700℃,800℃was studied. The surface morphology at 400℃and 800℃. the results show alloy was annealed in H2 atmosphere,the Al2O3 layer formed on the surface.The ability of oxidation resistance is better than 6N Cu.