Laser composite surfacing of copper for improved tribological properties

Abstract

Copper and its alloys are important engineering materials because of their excellent thermal and electrical conductivities. However, a relatively poor resistance to wear and erosion restrict its wide ranging applications. In the present study, commercially pure copper (of dimensions 20 × 20 × 10 μm) was subjected to laser composite surfacing by melting the surface of sand blasted copper using a continuous wave CO₂ laser and simultaneous deposition of a mixture of K₂TiF₆ and KBF₆ (in the weight ratio of 2 : 1) on the surface of molten copper. Following laser processing, a detailed study of the microstructure and phases of the surface layer was carried out and correlated with laser parameters. The mechanical (microhardness and wear resistance) properties of the surface layer were evaluated.