Laser induced Cu/alumina bonding: Microstructure and bond mechanism

The results of laser cladding of Cu to alumina under different treatment conditions and gas medium are presented. The laser surface treatment of alumina substrates was conducted by injection of copper powder into the laser–substrate interaction region. Processing parameters included the laser power, the scan speed of the laser beam, the copper feed rate and heat treatments following the laser treatment. Laser treated alumina substrates and the alumina–copper system, which was treated in air and under argon, were studied. Possible reactions at the metal–ceramic interface were investigated. Sub-micron Cu particles were formed in the amorphous grain boundary glass, and CuAlO2 phases were found in the alumina substrate after laser treatment.