Induction diffusion brazing of copper to aluminium

Abstract

The aim of this research was to develop an induction diffusion brazing to obtain a sound joint between copper and aluminium. A foil interlayer was used to bond copper to aluminium at 600°C for 2 s under a bonding pressure of 9 MPa. The failure of tensile test is in the aluminium side and no failure occurs when the joint is bent to 180°. The electrical resistivity of joint is lower than that of aluminium. The interfacial intermetallic compounds layers are Cu₉Al₄ and CuAl₂ with the total thickness of 2 μm. No voids and oxide scale are found in the joint. Heat treatment shows that induction diffusion brazing is superior to conventional flash welding to maintain electrical stability and mechanical integrity of copper to aluminium joint.

Keywords:

• Copper
• Aluminium
• Diffusion brazing
• Electrical resistivity
• Microstructure

Acknowledgements

The authors would like to acknowledge funding assistance provided by State Grid Corporation of China via Grant No. SGKJ[2010]14.