CN101181979A - Method for synthesizing cubic boron nitride by residual hexagonal boron nitride in high pressure synthesis of cubic boron nitride - Google Patents

Abstract

The invention relates to a method of synthesizing cubic boron nitride and leading surplus hexagonal BN to be synthesized into the cubic boron nitride under high pressure. Through soaking, table separation, panning, vacuum drying, mixing, pre-pressing molding, agglomerate assembling, high-pressure and high-temperature synthesis, grinding, purification, screening, modeling, finished product CBN single crystal is obtained. HBN material used in the method is usually disposed as waste residue. Through a series of technique processing, the method utilizes surplus HBN powder obtained after the CBN crystal is synthesized under high pressure and high temperature as a raw material and resynthesizes the CBN single crystal with accelerant, thus realizing recovery and recycling of waste and reducing production cost by 25-35 percent as well.

Description

The method of synthesizing cubic boron nitride by residual hexagonal boron nitride in high pressure synthesis of cubic boron nitride

Technical field:

The present invention relates to a kind of making emery wheel, grinding tool, be used for processing the method for the synthesizing cubic boron nitride by residual hexagonal boron nitride in high pressure synthesis of cubic boron nitride of ferrous metal and alloy thereof, the CBN monocrystalline is a kind of super hard abrasive, this abrasive material is still made the starting material of CBN micro mist, the CBN micro mist can be used as abrasive substance and uses, and also can be used as the starting material of superhard cutter.

Background technology:

CBN (cubic boron nitride) is raw material synthetic under ultra-high voltage (4.5-7.0GPa) high temperature (1400-2000 ℃) condition with HBN (hexagonal boron nitride).The HBN material of synthetic CBN generally uses boron-containing compound and the initial HBN of nitrogenous compound synthetic, yet, for studying through remaining HBN resynthesis CBN is unmanned all the time behind the synthetic CBN crystal of high pressure-temperature.

Summary of the invention:

The objective of the invention is to overcome the deficiency that prior art exists and provide a kind of use the synthetic CBN crystal of high pressure-temperature after remaining HBN powder be raw material, under the condition that has catalyst to participate in, carried out the method for the synthesizing cubic boron nitride by residual hexagonal boron nitride in high pressure synthesis of cubic boron nitride of resynthesis CBN monocrystalline.

The object of the present invention is achieved like this: make according to the following step:

A: the mixture that is soaked in water, make CBN and HBN and impurity soluble in water jointly, utilize the CBN physical properties different with HBN density, use shaking table that CBN and HBN and impurity are separated,

B: through eluriating repeatedly, remove basic metal catalyst impurity, residue HBN and water mixture be through the vacuum high-temperature drying, during anti-oxidation removal moisture, obtaining purified raw material HBN,

C: use mixer that raw material HBN and catalyst are mixed, applying pressure machine and mould are batch mixing compression moulding ear of maize jointly,

D: agalmatolite piece, conducting steel ring, carbon plate, carbon pipe, the certain method of the excellent foundation of pre-molding are assembled into pre-synthetic piece, and the employing six-plane piercer is in advance synthetic piece High Temperature High Pressure and keep the synthetic synthetic rod that obtains of certain hour,

E: synthetic rod through pulverizing, immersion, separation by shaking table, boil acid, boil alkali, a series of purification process such as to boil water, oven dry obtain work in-process CBN monocrystalline batch mixing,

F: the work in-process batch mixing obtains final product CBN monocrystalline through screening, type selecting operation.

The present invention has following positively effect: the HBN material that this method is used generally is to handle as waste residue, this method is handled by series of process, remaining hBN powder is raw material after using the synthetic cBN crystal of high pressure-temperature, under the condition that has catalyst to participate in, carried out resynthesis CBN monocrystalline, realize that Waste recovery utilizes again, 25-35% simultaneously reduces production costs.

Embodiment:

Embodiment: technical process: CBN after height is pressed into and HBN and mixtures of impurities

A (immersion, separation by shaking table)Residuum HBN and impurity

B (elutriation, vacuum-drying)Raw material HBN raw material HBN+ (10-20%) catalyst

C (mixing, pre-molding)Pre-molding rod agalmatolite piece+conducting steel ring+carbon plate+carbon pipe+pre-molding rod

D (be assembled into pre-synthetic piece, high pressure-temperature is synthetic)Synthetic rod

E (pulverize, purify)Work in-process CBN monocrystalline batch mixing

F (screening, type selecting)Final product CBN monocrystalline

The procedure technology condition:

A: the mixture that is soaked in water, make CBN and HBN and impurity soluble in water jointly, utilize the CBN physical properties different with HBN density, use shaking table that CBN and HBN and impurity are separated.

B: through eluriating repeatedly, remove basic metal catalyst impurity, residue HBN and water mixture be through the vacuum high-temperature drying, during anti-oxidation removal moisture, to obtain purified raw material HBN.

C: use mixer that raw material HBN and catalyst are mixed, applying pressure machine and mould are batch mixing compression moulding ear of maize jointly.

D: agalmatolite piece, conducting steel ring, carbon plate, carbon pipe, the certain method of the excellent foundation of pre-molding are assembled into pre-synthetic piece, and the employing six-plane piercer is in advance synthetic piece High Temperature High Pressure and keep the synthetic synthetic rod that obtains of certain hour.

E: synthetic rod through pulverizing, immersion, separation by shaking table, boil acid, boil alkali, a series of purification process such as to boil water, oven dry obtain work in-process CBN monocrystalline batch mixing.

F: the work in-process batch mixing obtains final product CBN monocrystalline through screening, type selecting operation.

Claims (1)

1. the method for a synthesizing cubic boron nitride by residual hexagonal boron nitride in high pressure synthesis of cubic boron nitride is characterized in that: make according to the following step:

A: the mixture that is soaked in water, make CBN and HBN and impurity soluble in water jointly, utilize the CBN physical properties different with HBN density, use shaking table that CBN and HBN and impurity are separated,

B: through eluriating repeatedly, remove basic metal catalyst impurity, residue HBN and water mixture be through the vacuum high-temperature drying, during anti-oxidation removal moisture, obtaining purified raw material HBN,

C: use mixer that raw material HBN and catalyst are mixed, applying pressure machine and mould are batch mixing compression moulding ear of maize jointly,

D: agalmatolite piece, conducting steel ring, carbon plate, carbon pipe, the certain method of the excellent foundation of pre-molding are assembled into pre-synthetic piece, and the employing six-plane piercer is in advance synthetic piece High Temperature High Pressure and keep the synthetic synthetic rod that obtains of certain hour,

E: synthetic rod through pulverizing, immersion, separation by shaking table, boil acid, boil alkali, a series of purification process such as to boil water, oven dry obtain work in-process CBN monocrystalline batch mixing,

F: the work in-process batch mixing obtains final product CBN monocrystalline through screening, type selecting operation.