THERMAL BARRIER COMPOUND, SUPERALLOY MECHANICAL PART COATED WITH SUCH A COMPOUND, CERAMIC COATING, AND PROCESS FOR MANUFACTURING THE SAID COATING

摘要

The invention relates to a thermal conductivity barrier composition of low conductivity and high thermomechanical resistance in ceramic. Typically, this composition comprises a zirconia base, at least one trivalent oxide, making it possible to stabilize the zirconia and to reduce the thermal conductivity of the zirconia optimally, and at least one pentavalent oxide making it possible to reduce the rate of vacancies. oxygen to substantially bring it back to that of a partially stabilized zirconia. Preferably, said trivalent oxide is present with a molar proportion consisting of a first portion for partially stabilizing the zirconia and a second portion which introduces point defects in the network and in that said pentavalent oxide is present with a proportion molar equal to said molar proportion of said second part of the trivalent oxide. Application to the production of a superalloy mechanical part (12), comprising a ceramic coating (11, 14) having this composition, and a possible bonding sub-layer (13).