FORMATION OF HEAT INSULATING COATING SERIES

• Main Authors: BRUCE ROBERT W, RIGNE JOSEPH DAVID, MARICOCCHI ANTONIO FRANK, WORTMAN DAVID JOHN, RIGNEY DAVID VINCENT
• Format: Patent
• Language: English
• Published: 04.04.2000
• Edition: 7
• Subjects: CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; METALLURGY; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION

PROBLEM TO BE SOLVED: To provide a method for forming a heat insulating coating having resistance to spalling of gas turbine engine parts to be exposed to high temperature and also having low thermal conductivity. SOLUTION: A bonding coat is formed on the surface of parts 12, and then grit blasting is applied to the bonding coat by the medium of abrasives having 250-300 μm grain size. The parts 12 are supported in a coating chamber 10 containing an ingot 16 of desired ceramic material. An oxygen-containing gas has at least 0.006 mbar partial pressure of oxygen. The surface of the parts 12 is preheated to 1100 deg.C. The ceramic material, composed of yttria - stabilized zirconia, is evaporated by an electron beam at a rate of about 23.5 to 29.2 grams per minute.