| 摘要 |
PROBLEM TO BE SOLVED: To elongate the life of a coating for a super alloy and other base materials, in a method for forming a thermal barrier coating.SOLUTION: An outwardly grown diffusion aluminide bonding layer is formed on a superalloy substrate and has higher concentrations of Al and Pt and lower concentrations of harmful impurities (e.g. Mo, W, Cr, Ta, S, etc.) at an outermost region of the bonding layer than at an innermost region thereof adjacent the substrate. The bonding layer is pretreated prior to deposition of a ceramic thermal insulative layer in a manner that reduces grain boundary ridges on the outermost bonding layer surface without adversely affecting the outermost region thereof, and then is heat treated to thermally grow a stable alpha alumina layer on the bonding layer. |
