Thermal barrier composition and a ceramic coating having such a composition

• Main Authors: MALIE ANDRE, SAINT-RAMOND BERTRAND, LECLERCQ BERANGERE, MEVREL REMY, AZZOPARDI ALBAN
• Format: Patent
• Language: English
• Published: 20.05.2008
• Subjects: AIR INTAKES FOR JET-PROPULSION PLANTS; ARTIFICIAL STONE; BLASTING; CEMENTS; CERAMICS; 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; COMBUSTION ENGINES; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDINGMATERIALS; CONCRETE; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS; DIFFUSION TREATMENT OF METALLIC MATERIAL; ENGINE PLANTS IN GENERAL; GAS-TURBINE PLANTS; HEATING; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; LAYERED PRODUCTS; LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT ORNON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM; LIGHTING; LIME, MAGNESIA; MACHINES OR ENGINES IN GENERAL; MECHANICAL ENGINEERING; METALLURGY; NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAMTURBINES; PERFORMING OPERATIONS; REFRACTORIES; SLAG; STEAM ENGINES; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; TRANSPORTING; TREATMENT OF NATURAL STONE; WEAPONS

The invention relates to a ceramic thermal barrier composition of low conductivity and high high-temperature strength. In characteristic manner, the composition comprises a zirconia base, at least one trivalent oxide enabling the zirconia to be stabilized and enabling the thermal conductivity of the zirconia to be reduced in optimum manner, and at least one pentavalent oxide enabling the content of oxygen vacancies to be reduced so as to make it substantially equal to that of a partially stabilized zirconia. Preferably, said trivalent oxide is present with a molar content constituted by a first portion enabling the zirconia to be stabilized partially and a second portion which introduces point defects into the lattice said pentavalent oxide is present with a molar concentration equal to said molar concentration of said second portion of the trivalent oxide. The invention is applicable to making a superalloy machine part having a ceramic coating with said composition, and possibly also a bonding underlayer.