Abstract: Disclosed is a multilayer sintered ceramic body comprising at least one first layer comprising at least one crystalline phase of YAG, wherein the at least one first layer has at least one surface; and at least one second layer comprising alumina and at least one of stabilized zirconia and partially stabilized zirconia, wherein the at least one surface of the at least one first layer comprises pores wherein the pores have a maximum size of from 0.1 to 5 um as measured by SEM, and wherein each of the at least one first layer and the at least one second layer has a coefficient of thermal expansion (CTE), wherein the CTE of the at least one first layer and the CTE of the at least one second layer differ from 0 to 0.6×10?6/° C. as measured in accordance with ASTM E228-17. Methods of making are also disclosed.

Abstract: Disclosed herein are plasma chamber components that comprise a ceramic sintered body comprising at least one first layer comprising a surface having a surface area and at least one crystalline phase of from 90% to 99.8% by volume of poly crystalline yttrium aluminum garnet (YAG), at least one second layer comprising alumina and zirconia wherein the zirconia comprises at least one of stabilized and partially stabilized zirconia, and optionally, at least one third layer comprising at least one selected from the group consisting of YAG, alumina, and zirconia.

Abstract: Disclosed herein is a sintered yttrium oxide body having a total impurity level of 40 ppm or less, a density of not less than 4.93 g/cm3, wherein the sintered yttrium oxide body has at least one grain boundary comprising silica in an amount of not less than 1 to not greater than 10 atoms/nm2 wherein the sintered yttrium oxide body has at least one surface comprising at least one pore, wherein no pore is larger than 5 ?m in diameter. A process for making the sintered yttrium oxide body is also disclosed.

Abstract: A spark plasma sintering tool. The tool comprises a die including an inner wall having a diameter that defines an inner volume configured to receive a ceramic powder, and an upper punch and a lower punch operably coupled with the die, wherein each of the upper and lower punches have an outer wall defining a diameter that is less than the diameter of the inner wall of the die thereby creating a gap from 10 ?m to 100 ?m wide between each of the punches and the inner wall of the die when at least one of the punches moves within the inner volume of the die. Also disclosed is a method of using the tool to create a large sintered ceramic body and a computer readable medium storing processor-executable instructions adapted to cause one or more computing devices to operate the tool.

Abstract: A method of making a sintered ceramic body comprising the steps of disposing a ceramic powder (5) inside an inner volume of a spark plasma sintering tool (1), wherein the tool comprises: a die (2) comprising a sidewall comprising inner and outer walls, wherein the inner wall has a diameter defining the inner volume; upper and lower punches (4,4?) operably coupled with the die, wherein each of the punches have an outer wall defining a diameter less than the diameter of the die inner wall, thereby creating a gap (3) between the punches and the inner wall when at least one of the punches are moved within the inner volume, and the gap is from 10 ?m to 70 ?m wide; creating vacuum conditions inside the inner volume; moving at least one of the punches to apply pressure to the ceramic powder while heating, and sintering; and lowering the temperature of the sintered body.