WEAR-RESISTANT COATING, OXIDATION AND CORROSION PROTECTIVE COATING, CORROSION- AND WEAR-RESISTANT COATING ALLOY, ITEM PROVIDED WITH SUCH A COATING AND METHOD FOR PRODUCING SUCH A COATING

摘要

A protectively coated superalloy has improved oxidation, corrosion, and wear resistance at elevated temperatures. The protective coating is a MCrAlY type alloy having a carbon content of 0.6 to 11 percent and is characterized in a preferred embodiment by having a carbon bearing matrix containing metal carbides of 1-2 microns mean size and chromium carbides of less than 12 microns. The coating is produced in plasma spraying a mixture of MCrAlY and CR3C2 powders to form a coating having both fine carbides and coarser Cr3C2 carbides in an MCrAlY matrix. Heat treatment at 1080 DEG C after coating bonds the substrate and coating and forms further fine carbides.