Improved diffusion coating process and products.

摘要

Process for producing novel nickel superalloy bodies having increased resistance of to oxidation and corrosion at high temperatures. The process comprises applying a thin layer of a platinum-group metal and heating to an elevated temperature to diffuse or integrate the platinum-group metal into the surface of the metal superalloy. Then the superalloy body is packed into a container filled with a diffusion powder composition containing sources of aluminum and chromium metals and heated in an inert gas atmosphere to an elevated temperature to codeposit and diffuse aluminum and chromium into the platinum-group metal-treated surface. Finally, the superalloy body is removed from the diffusion coating container and heated to the solvus temperature to form a ductile surface having an outer Zone microstructure comprising PtAl2 which has been ductilized by the solutioning of beta chromium. This ductilized PtAl2 may or may not be in a beta phase nickel aluminide matrix depending on substrate composition.