Ceramic body comprising silicon carbide and method of forming same
A method of forming a ceramic body including forming a mixture made of at least a first powder material (PM 1 ) including carbon having a first average particle size (PS 1 ), a second powder material (PM 2 ) including carbon and different than the first powder material, the second powder material having a second average particle size (PS 2 ) less than the first average particle size (PS 1 ), and an aluminum content (AC 2 ) greater than the aluminum content (AC 1 ) of the first powder material, and further including forming a green body from the mixture, and sintering the green body and forming a ceramic body having a first type of grain having an average grain size of not greater than about 8 times the first average particle size (PS 1 ).
1. A ceramic component, comprising:
a silicon carbide body including:
a first type of grain having a first average grain size, and
a second type of grain having a second average grain size and an elongated structure,
wherein:
the silicon carbide body of the ceramic component includes an aluminum content of not greater than about 800 ppm, and at least about 100 ppm; and
the second average grain size is at least 1.1 times greater than the first average grain size.
2. The ceramic component of claim 1 , wherein the silicon carbide body comprises a second type grain concentration in a range of 4 per mm 2 to 34 per mm 2 .
3. The ceramic component of claim 1 , wherein the silicon carbide body has at least 52 vol % of the first type of grain for the total volume of the silicon carbide body.
4. The ceramic component of claim 1 , wherein the second type of grain has an average aspect ratio of greater than 3, wherein the aspect ratio is a measure of length to width, and length is longer than the width.
5. The ceramic component of claim 1 , wherein the first average grain size is no greater than 15 microns.
6. The ceramic component of claim 1 , wherein the second average grain size is at least 20 microns.
7. The ceramic component of claim 1 , wherein the second average grain size is at least 30 microns.
8. The ceramic component of claim 1 , wherein:
a relative grain size difference between the first type of grain and the second type of grain is based on a following equation
(
GS
2
-
GS
1
)
GS
2
×
100
%
;
and
the relative grain size difference is at least 10%.
9. The ceramic component of claim 1 , wherein the silicon carbide body is essentially free of a material selected from the group consisting of silicon metal, aluminum nitride, an oxide material, a nitride material, a boride material, and a combination thereof.
10. The ceramic component of claim 1 , wherein the aluminum content of the silicon carbide body is in a range of 100 ppm to 600 ppm.
11. A ceramic component, comprising:
a silicon carbide body including:
a first type of grain having a first average grain size (GS 1 ), and
a second type of grain having a second average grain size (GS 2 ) and an elongated structure,
wherein:
the second type of grain within the ceramic component includes aluminum, wherein the aluminum is at an aluminum content of not greater than 3000 ppm;
the silicon carbide body includes an aluminum content of not greater than about 800 ppm and at least about 100 ppm;
a relative grain size difference between the first type of grain and the second type of grain is based on a following equation
(
GS
2
-
GS
1
)
GS
2
×
100
%
;
and
the relative grain size difference is at least 10%.
12. The ceramic component of claim 11 , wherein the relative grain size difference is at least 40%.
13. The ceramic component of claim 11 , wherein the first type of grain consists essentially of silicon carbide.
14. The ceramic component of claim 11 , wherein the silicon carbide body is essentially free of a material selected from the group consisting of silicon metal, aluminum nitride, an oxide material, a nitride material, a boride material, and a combination thereof.
15. The ceramic component of claim 11 , wherein the silicon carbide body comprises a second type grain concentration in a range of 4 per mm 2 to 34 per mm 2 .
16. A ceramic component, comprising:
a silicon carbide body including:
a first type of grain having a first average grain size, and
a second type of grain having a second average grain size and an elongated structure,
wherein:
the silicon carbide body of the ceramic component includes an aluminum content in a range of 100 ppm to 800 ppm;
the second type of grain has an average aspect ratio of at least 2, wherein the aspect ratio is a measure of length to width, and length is longer than the width.
17. The ceramic component of claim 16 , wherein the silicon carbide body comprises a second type grain concentration in a range of 4 per mm 2 to 34 per mm 2 .
18. The ceramic component of claim 16 , the second type of grain has an average aspect ratio of at least 3.
19. The ceramic component of claim 16 , wherein the second type of grain has an average aspect ratio that is larger as compared to the first type of grain.