Laser sintering (SLS) of hard metal powders for abrasion resistant coatings

Selective laser sintering (SLS), one of the new RP, RT and RM techniques, may be able to provide a process to form hard coating, which increases the life of machine parts in abrasive conditions. It is known that cemented carbide (WC–Co) parts can be made by this technology, although not to full density. A porous shell of WC–Co, shaped to fit closely over the surface of a part subjected to wear, might be manufactured by SLS. Infiltration by a matrix metal such as bronze can achieve full density and also braise the shell to the part. This paper presents preliminary results on the influence of powder size and shape and % Co on the ability to create coherent layers of hard material, and on how coating microstructure varies with laser sintering conditions. It further presents the results of sand abrasion wear tests.