HEAT TREATED CERAMIC SUBSTRATE HAVING CERAMIC COATING

摘要

A heat treated ceramic article includes a ceramic substrate and a ceramic coating on the ceramic substrate. The ceramic coating is a non-sintered ceramic coating that has a different composition than the ceramic substrate. The heat treated ceramic article further includes a transition layer between the ceramic substrate and the ceramic coating, the transition layer comprising first elements from the ceramic coating that have reacted with second elements from the ceramic substrate, wherein the transition layer has a thickness of about 0.1 microns to about 5 microns.

主权项

1. A ceramic article comprising a ceramic substrate and a ceramic coating on the ceramic substrate, the ceramic article having been prepared by a process comprising:
performing a thermal spraying process to form the ceramic coating on the ceramic substrate, the ceramic coating having an initial porosity and an initial amount of cracking; heating the ceramic article to a temperature range between about 1000° C. and about 1800° C. at a ramping rate of about 0.1° C. per minute to about 20° C. per minute; performing heat treatment of the ceramic article at one or more temperatures within the temperature range for a duration of up to about 24 hours to reduce a porosity of the ceramic coating to below the initial porosity and to reduce an amount of cracking of the ceramic coating to below the initial amount of cracking, wherein the ceramic article is heat treated at below a sintering temperature for the ceramic coating to prevent sintering of the ceramic coating; and cooling the ceramic article at the ramping rate after the heat treatment, wherein after the heat treatment the ceramic coating is not sintered, has a reduced amount of cracking that is below the initial amount of cracking, and has a reduced porosity that is below the initial porosity.