구리-알루미늄 이종재료의 브레이징 특성에 관한 연구

Abstract

The application of nonferrous metals is increasing in terms of cost cutting and diversity of use of materials and developments of engineering technology. The need of conjugation between composite materials is regarded as important topic as components and machines get miniaturized. Especially sharp rise of copper’s price, there were demands for other materials. Aluminum can substitute copper as it has comparatively good corrosiveness, easy to make, inexpensive and etc. However copper and aluminum is not suitable for conjugation as it has different material property. It easily produces vulnerable intermetallic compounds so it is hard to get desirable strength. Therefore we researched about characteristic of brazing of copper and aluminum using five different filler metal. Before proceed to brazing, we investigated surface treatment and wetting characteristic with respect to the surface treatment. we made conditions for conjugation considering the result. We plated aluminum with zinc, nickel, copper and conjugated using five types of filler metals. After conjugation we did tensile test to find out material property and progressed componential analysis through EPMA test. In result we found out copper has desirable strength as most of specimens broke at the base metal of copper. Also there was a decrease of strength due Al2Cu intermetallic compound inside of filler metal according to the result of EPMA measurement.