Coating titanium alloy turbine blade tip

摘要

An abrasive layer is formed on the tip portion of a turbine engine blade made of Ti alloy by (a) electroplating a 12-18 microns thick first Ni layer onto the blade tip; (b) electroplating a max. 1 micron thick second Ni layer; (c) electroplating a third Ni layer, immersing the tip in a slurry of electrically non-conductive particles in an electroplating soln. present on a membrane which is permeable to electric current and the soln., and then contg. electroplating of the third Ni layer; (d) electroplating a fourth Ni layer such that the combined thickness of the third and fourth layers corresponds to 50-95% of the mean dimension of the embedded particles, and (e) heat treating the blade to cause diffusion between the first Ni layer and the blade tip.