Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
93 words
Composite sintered Si 3 N 4 material consisting of: a sintered Si 3 N 4 substrate containing 0.1 to 10 weight % of Y 2 0 3 and 0.1 to 10 weight % of ZrO 2 and the balance being of Si 3 N 4 ; a first layer of Ti compound coated on the sintered Si 3 N 4 substrate; a second layer of A1 2 0 3 coated on the first layer; and the total thickness of the first and second layers being in the range of 1 to 20 microns.
Claim 2
Dependent Claim
93 words
Composite sintered Si 3 N 4 material consisting of: a sintered Si 3 N 4 substrate containing 0.1 to 10 weight % of Y 2 0 3 and 0.1 to 10 weight % of ZrO 2 and the balance being of Si 3 N 4 ; a first layer of Ti compound coated on the sintered Si 3 N 4 substrate; a second layer of A1 2 0 3 coated on the first layer; and the total thickness of the first and second layers being in the range of 1 to 20 microns.
Claim 3
Dependent Claim
56 words
Composite sintered Si 3 N 4 material as claimed in Claim 1, wherein the sintered Si 3 N 4 substrate further contains 1 to 15 weight % of at least one member selected from the group consisting of compound and solid solution thereof of elements of IVa (except Zr), Va and VIa of the Periodic Table.
Claim 4
Dependent Claim
33 words
Composite sintered Si 3 N 4 material as claimed in Claim 2, wherein the compound of elements of IVa (except Zr), Va and VIa of the Periodic Table includes carbide, nitride, carbonitride thereof.
Claim 5
Dependent Claim
25 words
Composite sintered Si 3 N 4 material as claimed in anyone of Claims 1 to 3, wherein ZrO 2 has been stabilized to cubic Zr02.
Claim 6
Dependent Claim
44 words
Composite sintered Si 3 N 4 material as claimed in Claim 4, wherein Zr0 2 has been stabilized to cubic Zr0 2 by the addition of at least one member selected from the group consisting of CaO, MgO and Y 2 0 3 .
Claim 7
Dependent Claim
34 words
Composite sintered Si 3 N 4 material as claimed in anyone of Claims 1 to 5, wherein the mean grain size of the sintered Si 3 N 4 substrate is smaller than 3 microns.
Claim 8
Dependent Claim
31 words
Composite sintered Si 3 N 4 material as claimed in anyone of Claims 1 to 6, wherein the first and second layers have respectively a thickness of 3 to 10 microns.
Claim 9
Dependent Claim
26 words
Composite sintered Si 3 N 4 material as claimed in Claim 7, wherein the first and second layers have a substantially same thickness with each other.
Claim 10
Dependent Claim
28 words
Composite sintered Si 3 N 4 material as claimed in anyone of Claims 1 to 8, wherein the first layer has a thickness of 0.5 to 10 microns.
Claim 11
Dependent Claim
28 words
Composite sintered Si 3 N 4 material as claimed in anyone of Claims 1 to 9, wherein the second layer has a thickness of 1 to 10 microns.
Claim 12
Dependent Claim
44 words
Composite sintered Si 3 N 4 material as claimed in anyone of Claims 1 to 10, wherein the first layer includes at least one member selected from the group consisting of Ti carbide, Ti nitride, Ti carbonitride, Ti oxide and the solid solution thereof.
Claim 13
Dependent Claim
31 words
Cutting tool mainly for use in cutting cast iron at high speed and made from the composite sintered Si 3 N 4 material described in anyone of Claims 1 to 11.