陶瓷表面制备铜基金属覆层工艺及结合机理

The Cu-based metal coating was fabricated on AlN ceramic substrate by pulsed YAG laser and the process was optimized by adjusting laser cladding process parameters. Preheating and slow cooling rate were utilized in the process to reduce the cracking tendency of ceramic substrate. The reactive metal titanium powder was added to enhance wettability of AlN ceramic substrate. The results showed that transition layer appeared between ceramic substrate and Cu-based metal and the thickness of the transition layer increased with the increasing current. The content of titanium increased firstly and then decreased from the ceramic substrate to the Cu-based alloy coating, so did that of oxygen element, while the other elements including Cu, Al and N had presented a smooth trasition. The metallurgical bonding was produced between the ceramic substrate and the cladding powder with different products including TiO₂, Ti₃Al, Cu₄Ti₅, Al₂TiO₅ and Ti₂N.