Bonded alumina coating for stainless steel

摘要

A method for manufacturing an alumina-based layer structure having transition regions between layers is disclosed. The method may include ion milling a stainless steel structure surface to partially reduce a metal oxide layer from, and create an exposed portion of, the surface. The method may include oxidizing the exposed portion of the surface to form a crystallized metal oxide bonding layer, growing a crystallized alumina layer onto the metal oxide bonding layer, and diffusing metal from the surface into the crystallized alumina layer, to form a graded aluminate spinel layer. The method may include forming a first transition region from the graded aluminate spinel layer to a crystalline alumina layer, growing the crystalline alumina layer from the first transition region, forming a second transition region from the crystalline alumina layer to an amorphous alumina layer, and growing the amorphous alumina layer from the second transition region.

主权项

1. A method for manufacturing, in a deposition chamber, an alumina-based layer structure having transition regions between layers, the method comprising: milling, in-situ, a stainless steel structure with an ion beam to at least partially remove carbon-based contaminants, to at least partially reduce a metal oxide layer from a surface of the stainless steel structure and to create an exposed portion of the stainless steel structure; crystallizing, by oxidizing, the exposed portion of the stainless steel structure to form a crystallized metal oxide bonding layer; forming, by growing a crystallized alumina layer onto the metal oxide bonding layer and diffusing metal from the stainless steel surface into the crystallized alumina layer, a graded aluminate spinel layer on the crystallized metal oxide bonding layer; forming a first transition region, wherein the first transition region includes a metal concentration gradient between the graded aluminate spinel layer and the crystalline alumina layer, from the graded aluminate spinel layer to a crystalline alumina layer; growing the crystalline alumina layer from the first transition region; forming a second transition region, wherein the second transition region includes a crystalline structure gradient between the crystalline alumina layer and the amorphous alumina layer, from the crystalline alumina layer to an amorphous alumina layer; growing the amorphous alumina layer from the second transition region.