Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
114 words
An alumina-zirconia-silicon carbide sintered ceramic composite having high strength and high hardness, said sintered ceramic composite being prepared from a mixture consisting essentially of 5 to 50 volume percent of partially stabilized zirconia powder of mean particle size between 0.1 and 1.0 μm, 3 to 40 volume percent of silicon carbide whiskers of 1 μm or less in diameter with an aspect ratio between 3 and 200, said aspect ratio being the ratio of the length of a whisker to its diameter, the balance of said mixture being substantially alumina powder, wherein the sum of the amounts of zirconia and silicon carbide accounts for 55 volume percent at most of the total powder mixture.
Claim 2
Dependent Claim
114 words
An alumina-zirconia-silicon carbide sintered ceramic composite having high strength and high hardness, said sintered ceramic composite being prepared from a mixture consisting essentially of 5 to 50 volume percent of partially stabilized zirconia powder of mean particle size between 0.1 and 1.0 μm, 3 to 40 volume percent of silicon carbide whiskers of 1 μm or less in diameter with an aspect ratio between 3 and 200, said aspect ratio being the ratio of the length of a whisker to its diameter, the balance of said mixture being substantially alumina powder, wherein the sum of the amounts of zirconia and silicon carbide accounts for 55 volume percent at most of the total powder mixture.
Claim 3
Dependent Claim
27 words
An alumina-zirconia-silicon carbide sintered ceramic composite as claimed in claim 1, wherein said partially stabilized zirconia powder contains up to 2 mole percent of yttria for stabilization.
Claim 4
Dependent Claim
23 words
An alumina-zirconia-silicon carbide sintered ceramic composite as claimed in claim 2, wherein the volume ratio of alumina, zirconia, and silicon carbide is 70:15:15.
Claim 5
Dependent Claim
23 words
An alumina-zirconia-silicon carbide sintered ceramic composite as claimed in claim 2, wherein the volume ratio of alumina, zirconia, and silicon caride is 80:15:5.
Claim 6
Dependent Claim
138 words
A process for manufacturing an alumina-zirconia-silicon carbide sintered ceramic composite having high strength and high hardness, said process comprising the steps of preparing a mixture by mixing 5 to 50 volume percent of partially stabilized zirconia powder of mean particle size between 0.1 and 1.0 μm, 3 to 40 volume percent of silicon carbide whiskers of 1 μm or less in diameter with an aspect ratio between 3 and 200, said aspect ratio being the ratio between the length of a whisker and its diameter, the balance of said mixture being substantially alumina powder, wherein the sum of the amounts of zirconia and silicon carbide accounts for 55 volume percent at most of the total mixture; molding the obtained mixture into a molded body, and then sintering the molded body at a temperature between 1400° and 1800° C.
Claim 7
Dependent Claim
138 words
A process for manufacturing an alumina-zirconia-silicon carbide sintered ceramic composite having high strength and high hardness, said process comprising the steps of preparing a mixture by mixing 5 to 50 volume percent of partially stabilized zirconia powder of mean particle size between 0.1 and 1.0 μm, 3 to 40 volume percent of silicon carbide whiskers of 1 μm or less in diameter with an aspect ratio between 3 and 200, said aspect ratio being the ratio between the length of a whisker and its diameter, the balance of said mixture being substantially alumina powder, wherein the sum of the amounts of zirconia and silicon carbide accounts for 55 volume percent at most of the total mixture; molding the obtained mixture into a molded body, and then sintering the molded body at a temperature between 1400° and 1800° C.
Claim 8
Dependent Claim
16 words
A process as claimed in claim 5, wherein said temperature is between 1450° and 1750° C.
Claim 9
Dependent Claim
28 words
A process as claimed in claim 5, wherein said mixture is sintered in an argon gas atmosphere at a temperature between 1700° and 1800° C. under atmospheric pressure.
Claim 10
Dependent Claim
27 words
A process as claimed in claim 5, wherein said mixture is sintered in a nitrogen gas atmosphere at a temperature between 1400° and 1700° C. under pressure
Claim 11
Dependent Claim
43 words
A process as claimed in claim 8, wherein prior to the sintering step, said mixture is placed in a furnace, then the pressure inside the furnace is reduced by pumping while the temperature in the furance is maintained between 400° and 1000° C.
Claim 12
Dependent Claim
38 words
A process as claimed in claim 5, wherein said mixture is made on a ball mill that is equipped with a pot made of at least one of the ceramic materials of which said sintered ceramic is composed.
Claim 13
Dependent Claim
21 words
A process as claimed in claim 10, wherein said mixture is made on a ball mill equipped with an alumina pot.