Cubic boron nitride sintered body and method for making the same
A cubic boron nitride sintered body is provided having improved strength and hardness for serving as a cutting tool. The sintered body includes cBN dispersed in a binder material, wherein the binder includes alumina, at least one other aluminum compound, and a non-aluminum material such as a carbide, nitride, carbonitride, boride or silicide of Groups IVa, Va, and VIa of the periodic table, or a mixture thereof.
1 . A wear resistant sintered compact comprising:
about 10 to about 50 vol. % of cBN particles;
about 30 to about 50 vol. % of aluminum oxide;
about 1 to about 25 vol. % of an aluminum-containing material other than aluminum oxide; and
at least one material selected from the group consisting of carbides, nitrides, carbonitrides, borides and suicides of Groups IVa, Va, and VIa of the periodic table.
2 . The sintered compact of claim 1 , wherein the cBN particles are uniformly dispersed within the compact.
3 . The sintered compact of claim 1 , wherein the cBN particles are about 1 to about 15 microns in size.
4 . The sintered compact of claim 1 , wherein the at least one material in the binder comprises a Group IV metal.
5 . The sintered compact of claim 1 , wherein the at least one material in the binder comprises TiN, TiC, TiB 2 , or TiCN.
6 . The sintered compact of claim 1 , wherein the aluminum oxide has a particle size of about 0.1 to about 5 microns in size.
7 . The sintered compact of claim 1 , wherein the compact comprises about 35 to about 45 vol. % of aluminum oxide.
8 . The sintered compact of claim 1 , wherein the compact comprises about 25 to about 50 vol. % cBN particles.
9 . The sintered compact of claim 1 , wherein the an aluminum-containing material comprises elemental aluminum, aluminum nitride, aluminum boride, or mixtures thereof.
10 . The sintered compact of claim 1 , wherein the cBN particles are coated with at least one layer of a carbide forming material.
11 . A method for manufacturing a sintered compact comprising:
providing a mixture, wherein the mixture is at least substantially homogenous and comprises:
about 10 to about 50 vol. % cBN particles;
about 30 to about 50 vol. % aluminum oxide;
about 1 to about 25 vol. % of a source of an aluminum-containing material that is not aluminum oxide; and
at least one material selected from the group consisting of carbides, nitrides, carbonitrides, borides and silicides of Groups IVa, Va, and VIa of the periodic table; and
sintering the mixture into a coherent body at a pressure of at least 3 GPa and a temperature above 1000° C.
12 . The method of claim 11 , wherein the cBN particles are about 1 to about 15 microns in size.
13 . The method of claim 11 , wherein the at least one material comprises a Group IV metal.
14 . The method of claim 11 , wherein the at least one material is selected from the group consisting of TiN, TiC, TiB 2 , and TiCN.
15 . The method of claim 11 , wherein the aluminum oxide particles have a particle size of about 0.1 to about 5 microns.
16 . The method of claim 11 , wherein the mixture comprises about 35 to about 45 vol. % of aluminum oxide.
17 . The method of claim 11 , wherein the mixture comprises about 25 to about 50 vol. % of cBN particles.
18 . The method of claim 11 , wherein the cBN particles are coated with at least one layer of a carbide forming material.
19 . A method of machining a cast iron material comprising:
machining a surface of a cast iron material with a tool comprising an abrasive body, wherein the abrasive body comprises:
about 10 to about 50 vol. % cBN particles;
about 30 to about 50 vol. % aluminum oxide;
about 1 to about 25 vol. % of an aluminum-containing material compound other than aluminum oxide; and
at least one material selected from the group consisting of carbides, nitrides, carbonitrides, borides and silicides of Groups IVa, Va, and VIa of the periodic table.
20 . The method of claim 19 , wherein the cast iron material comprises at least one of ductile iron, nodular iron, compacted graphite iron, grey cast iron, and a spin-cast grey iron.