SINTERED BODY
A sintered body contains perovskite YAlO 3 (YAP) as a main phase exhibited in X-ray diffractometry, and has a Vickers hardness of 11 GPa or more. In the case where the sintered body contains a composition other than YAlO 3 , the composition preferably substantially consists of Y 3 Al 5 O 12 and Y 4 Al 2 O 9 . The sintered body preferably has an absolute density of 5.1 g/cm 3 or more. The sintered body preferably has an open porosity of 1% or less, and also preferably has an average crystal grain size of 10 μm or less.
1 . A sintered body comprising perovskite YAlO 3 as a main phase,
wherein the sintered body has a Vickers hardness of 11 GPa or more.
2 . The sintered body according to claim 1 ,
wherein the crystal phase other than YAlO 3 substantially consists of Y 3 Al 5 O 12 and/or Y 4 Al 2 O 9 .
3 . The sintered body according to claim 1 ,
wherein the sintered body has a density of 5.1 g/cm 3 or more.
4 . The sintered body according to claim 1 ,
wherein the sintered body has an open porosity of 1% or less.
5 . The sintered body according to claim 1 ,
wherein the sintered body has an average crystal grain size of 10 μm or less.
6 . A method for producing the sintered body according to claim 1 , the method comprising the steps of:
preparing a molded body made of a raw material powder that contains YAlO 3 and has an average particle size of 1 μm or less; and
sintering the molded body at a temperature of 1200° C. or more and 1700° C. or less under a pressure of 5 MPa or more and 100 MPa or less to obtain the sintered body.
7 . A method for producing the sintered body according to claim 1 , the method comprising the steps of:
molding a raw material powder that contains YAlO 3 and has an average particle size of 1 μm or less at a pressure applied of 20 MPa or more and 200 MPa or less to obtain a molded body; and
sintering the molded body at a temperature of 1400° C. or more and 1900° C. or less without applying a pressure.
8 . The method according to claim 6 ,
wherein the raw material powder that contains YAlO 3 and has an average particle size of 1 μm or less has a BET specific surface area of 7 m 2 /g or more and 13 m 2 /g or less.
9 . A plasma-resistant member having a surface that is to be exposed to plasma in a halogen-based gas atmosphere, wherein the sintered body according to claim 1 provides said surface.