Analyzing of Reaction Mechanisms of Cu-Al Intermetallic Compounds in Dipping Experiment of Cu Wire and Cu Plate into Al Melt by Cylindrical Reaction Model and Flat Plate Model - In Order to Analyze the Combustion Synthesis of Cu-Al Intermetallic Compounds

In our previous paper, dipping experiments of Cu wires and Cu plates into molten Al were investigated to analyze the combustion synthesis of Cu-Al intermetallic compounds. From the dipping experiments, it was found that Cu3Al compound layers were formed between the Cu base metal and the molten Al. The compound formation reactions were able to be almost simulated by calculating the cylindrical model and the flat plate reaction model. However, there are a few differences between Cu wire dipping experiment and Cu plate dipping experiment. Al concentration of Cu3Al compound phase formed in the Cu wire are higher than that of Cu plate. For the reaction parameters, diffusion coefficient of Al in Cu plate dipping experiment is also higher than that of Cu wire dipping experiment. For the dipping experiment of Cu wire, the reaction parameters are, log D'(Al.w)/[m(2).s(-1)] = -3.90 x 10(3)/T-7.50 log k(f.w)/[mol.m(-2).s(-1)] / = -6.98 x 10(3)/T-4.70 For the dipping experiment of Cu plate, the reaction parameters are, log D'(Al.p)/[m(2).s(-1)] = -2.59 x 10(3)/T-8.45 log k(f.p)/[mol.m(-2).s(-1)] = -8.50 x 10(3)/T+6.00 From analyzing the cylindrical model and the flat plate reaction model, it is guessed the differences were caused by the contact area of Cu/Cu3Al/Al interface and Al concentration of Cu3Al phase formed in Cu wires and Cu plates.