Sintered ceramic component and a process of forming the same

Abstract

A sintered ceramic component can have a final composition including at least 50 wt. % MgO and at least one desired dopant, wherein each dopant of the at least one desired dopant has a desired dopant content of at least 0.1 wt. %. All impurities (not including the desired dopant(s)) are present at a combined impurity content of less than 0.7 wt. %. A remainder can include Al 2 O 3 . The selection of dopants can allow for better control over the visual appearance of the sintered ceramic component, reduces the presence of undesired impurities that may adversely affect another part of an apparatus, or both. The addition of the dopant(s) can help to improve the sintering characteristics and density as compared to a sintered ceramic component that includes the material with no dopant and a relatively low impurity content.

What is claimed is: 
     
         1 . A sintered ceramic component having a final composition comprising:
 at least 50 wt. % MgO;   at least one desired dopant, wherein each dopant of the at least one desired dopant has a desired dopant content of at least 0.1 wt. %;   all impurities are present at a combined impurity content of less than 0.7 wt. %; and   a remainder comprising Al 2 O 3 .   
     
     
         2 . The sintered ceramic component of  claim 1 , wherein the at least one desired dopant includes CaO. 
     
     
         3 . The sintered ceramic component of  claim 2 , wherein the CaO content is at least 0.2 wt. %. 
     
     
         4 . The sintered ceramic component of  claim 1 , wherein the at least one desired dopant includes Y 2 O 3 . 
     
     
         5 . The sintered ceramic component of  claim 4 , wherein the Y 2 O 3  content is no greater than 3 wt. %. 
     
     
         6 . The sintered ceramic component of  claim 1 , wherein the at least one desired dopant includes TiO 2 . 
     
     
         7 . The sintered ceramic component of  claim 6 , wherein the TiO 2  content is no greater than 3 wt. % 
     
     
         8 . The sintered ceramic component of  claim 1 , wherein the at least one dopant includes a first dopant and a second dopant. 
     
     
         9 . The sintered ceramic component of  claim 1 , wherein MgO has a content that is in a range of 51 wt. % to 80 wt. %. 
     
     
         10 . The sintered ceramic component of  claim 1 , wherein Al 2 O 3  has a content that is in a range of 20 wt. % to 49 wt. %. 
     
     
         11 . The sintered ceramic component of  claim 1 , wherein the sintered ceramic component is a gas manifold. 
     
     
         12 . The sintered ceramic component of  claim 1 , wherein the sintered ceramic component is a component of a gas-to-liquid membrane system. 
     
     
         13 . The sintered ceramic component of  claim 1 , wherein the sintered ceramic component has a coefficient of thermal expansion from 25° C. to 1200° C. in a range of 9.0 ppm/° C. to 13.0 ppm/° C. 
     
     
         14 . A process of forming a sintered ceramic component comprising:
 combining a binder and at least one powder to form a green mixture, wherein the at least one powder includes:
 at least 50 wt. % MgO; 
 at least one desired dopant, wherein each dopant of the at least one desired dopant has a desired dopant content of at least 0.1 wt. %; 
 all impurities are present at a combined impurity content of less than 0.7 wt. %; and 
 a remainder comprising Al 2 O 3 ; 
   shaping the green mixture to form an object having a shape corresponding to the sintered ceramic component; and   sintering the object to form the sintered ceramic component having a final composition, wherein sintering is performed at a temperature less than 1600° C., and the sintered ceramic component has a density that is at least 90% of theoretical density.   
     
     
         15 . The process of  claim 14 , wherein sintering is performed at a temperature no greater than 1575° C. 
     
     
         16 . The process of  claim 14 , wherein the at least one desired dopant includes CaO. 
     
     
         17 . The process of  claim 14 , wherein the at least one desired dopant includes Y 2 O 3 . 
     
     
         18 . The process of  claim 14 , wherein the at least one desired dopant includes TiO 2 . 
     
     
         19 . The process of  claim 14 , wherein the at least one dopant includes a first dopant and a second dopant. 
     
     
         20 . The process of  claim 14 , wherein the sintered ceramic component has a coefficient of thermal expansion from 25° C. to 1200° C. in a range of 9.0 ppm/° C. to 13.0 ppm/° C., 10.3 ppm/° C. to 12.7 ppm/° C., or 10.6 ppm/° C. to 12.5 ppm/° C.