| 摘要 |
PURPOSE: To form a heat-shielding coating excellent in adhesion in a high-temp. corrosive environment by forming a joining layer of specified alloy, an oxide layer and a ceramic layer contg. an an oxide whisker on the surface of an alloy substrate. CONSTITUTION: An MCrAlX alloy contg. >=4% Al (M is one kind among Fe, Ni and Co or their combination, and X is a rare-earth element such as Y) is formed on the surface of a substrate 1 of Ni-base alloy, etc., by plasma spraying as a joining layer 2 in 0.1-0.2mm thickness. The surface of the joining layer 2 is heated to 800-950 deg.C in a gaseous mixture of O2 and Ar contg. steam and pheoxidized to form an Al2 O3 layer 3, and further the surface is plastic- worked to form the nucleus of an Al2 O3 whisker having a large aspect ratio. A heat-shielding ceramic layer 5 consisting of partially stabilized ZrO2 contg. 6-8% Y2 O3 is then formed on the Al2 O3 layer 3 in 0.2-0.3mm, and an Al2 O3 whisker 4 is grown therein to improve the adhesion to the joining layer 2. |
