Patent ID: 7919722

Claim:
A method of fabricating a yttria part, comprising: (a) sintering a yttria sample in a sintering atmosphere; (b) machining the sintered yttria sample to form a part; and (c) annealing the part; wherein (c) further comprises: (c1) exposing the part to an annealing gas in an enclosure; (c2) heating the part from a first temperature to a second temperature over a first time period; (c3) maintaining the part at the second temperature for a second time period; and (c4) cooling the part from the second temperature to the first temperature over a third time period; wherein at least one of the sintering and annealing is performed in an oxygen-containing atmosphere, and (c2) and (c4) are performed at respective predetermined heating and cooling rates, the predetermined heating and cooling rates being selected based on at least the sintering atmosphere.