Corrosion, Electrical and Mechanical Performance of Copper Matrix Composites Produced by Mechanical Alloying and Consolidation

FeAl, Fe3Al and CuNiAl intermetallic particles were added externally to pure copper (Cu) by mechanical alloying and thermal consolidation to obtain intermetallic particles reinforced composites (CuFeAl, CuFe3Al and Cu(CuNiAl)). The copper metal matrix composites (MMCs) were developed to increase their compressive mechanical resistance without reducing electrical conductivity for spot weld applications related to commercial UNS C1900 copper. Their electrical properties were assessed by electrical conductivity tests, measured in % of IACS (International Annealed Copper Standard), the mechanical properties were obtained by compressive test. Electrochemical impedance spectroscopy (EIS), Potentiodynamic polarization (PP), and Lineal polarization resistance (LPR) techniques, were employed to evaluate the corrosion behavior. The CuFeAl and CuFe3Al MMCs have the higher corrosion resistance along better electrical and mechanical properties. The electrical and mechanical properties observed are attributed to the presence of the intermetallic particles which induces chemical stability, high lattice order and low density. In the same way, the intermetallic additions induces an structural stability of the passive film preventing the growth of corrosive pittings as the diffusion of metal ions.