CN103752221A - Preparation method of ultrahard anti-abrasion PCD (Poly Crystal Diamond) material containing enhanced core - Google Patents
Preparation method of ultrahard anti-abrasion PCD (Poly Crystal Diamond) material containing enhanced core Download PDFInfo
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- CN103752221A CN103752221A CN201410025087.8A CN201410025087A CN103752221A CN 103752221 A CN103752221 A CN 103752221A CN 201410025087 A CN201410025087 A CN 201410025087A CN 103752221 A CN103752221 A CN 103752221A
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Abstract
The invention discloses a preparation method of an ultrahard anti-abrasion PCD (Poly Crystal Diamond) material containing an enhanced core. The enhanced-core-containing PCD (Poly Crystal Diamond) material is obtained by cutting cubic boron nitride (c-BN), cubic boron carbon nitride (c-BC2N), boron carbide (B4C) or nano twin-crystal cubic boron nitride (nt-CBN) serving as the enhanced core into small columns, burying the column bodies of the enhanced core into diamond micro powder, putting the diamond micro powder into a pyrophyllite block and performing synthesis under high-temperature and high-pressure conditions. The novel ultrahard anti-abrasion material prepared by the preparation method disclosed by the invention integrates two characteristics, which are similar to ultrahigh hardness of natural diamonds and toughness of a poly crystal material, of an ultrahard extreme material, so that the application ranges of the ultrahard extreme material and the PCD material are expanded and the increasing requirements on the performance of ultrahard anti-abrasion materials of the mechanical manufacturing and petroleum/geological exploration industries are met.
Description
Technical field
The present invention relates to one has added as cubic boron nitride c-BN, cube boron carbonitrides c-BC
2n, boron carbide B
4c or nano twin crystal cubic boron nitride nt-CBN, as the synthetic method of the polycrystalline diamond PCD superhard wear-resistant composite material of enhancing core, are a kind of new methods of HTHP sintering synthesizing superhard composite, belong to superhard material field.
Background technology
Polycrystalline diamond (PCD) has impayable excellent properties, as high hardness and wearability, low-friction coefficient, high thermal conductivity, high manufacturing accuracy etc., in automobile and aerospace field, wood working industry, electron trade, petroleum geology probing industry, wire die, glass-cutting processing, gem processing and other field, obtained using further widely.
PCD material is by sintering under high-temperature and high-pressure conditions, to form by the diamond particles of a large amount of selected random orientation particles the polycrystal obtaining, and has the characteristic of diamond and synneusis texture simultaneously, has higher hardness and splendid toughness.
But the defect of PCD material is also comparatively obvious.Because PCD substantially can adopt catalyst (bonding agent) in building-up process, catalyst (bonding agent) can not only promote diamond crystals growth, after reaching certain condition, also can impel diamond crystals to convert graphite to, simultaneously the coefficient of thermal expansion of different materials is not quite similar, and therefore adopts the phenomenons such as the reasons such as heat that the instrument of PCD produces when work can cause diamond crystals in PCD sliding interface to produce oxidation, graphitization, diffusion, bonding, thermal stress is broken.
PCD also has the performance of hardness deficiency under some special process fields and some special operation condition.These have all limited the application of polycrystalline diamond.
Cubic boron nitride c-BN, cube boron carbonitrides c-BC
2n, boron carbide B
4c and nano twin crystal cubic boron nitride nt-CBN etc. are the materials with ultrahigh hardness, and this different materials is only that single performance is outstanding, and high fragility is difficult to separately as a kind of integral material it.
As time goes on, the requirement of modern mechanical processing and manufacturing and oil, the Performance and quality of geological prospecting industry to ultra-hard abrasive material improves constantly.
Synthetic strong adaptability, the superhard material that has high rigidity and toughness concurrently are the extremely valuable research directions in current superhard material field.
Summary of the invention
The technical issues that need to address of the present invention are just to overcome the defect of prior art, a kind of preparation method who contains the polycrystalline diamond ultra-hard abrasive material that strengthens core is provided, novel super-hard wearing composite material prepared by the present invention, combine toughness two specific characters that superhard limiting material is similar to ultrahigh hardness and the glomerocryst material of natural diamond, having widened the range of application of superhard limiting material and glomerocryst material PCD, is also that the present situation that machine-building and oil, geological prospecting industry day by day improve ultra-hard abrasive material performance requirement provides a kind of settling mode.
For addressing the above problem, the present invention adopts following technical scheme:
The invention provides a kind of preparation method who contains the polycrystalline diamond ultra-hard abrasive material that strengthens core, described method comprises the following steps:
A, prepare superhard material and strengthen core: adopt laser cutting technique that enhancings core superhard material is cut into enhancing stem stem body;
B, screening diadust: in diadust, 325-460 order accounts for 8-15 part, and 460-700 order accounts for 8-20 part, and 700-1200 order accounts for 50-70 part, and 1200-1800 order accounts for 10-30 part;
C, pressed by powder: in bonding agent, than the mass ratio of powder gross mass, be 1:(5-20) ratio in diadust, add bonding agent to mix, and compound is packed in porous graphite post, one or more are strengthened to stem stem body and imbed in diadust compound, vacuum reduction;
D, synthetic: porous graphite post is put into pyrophyllite block and assemble, the pyrophyllite block that assembling is completed is put into press, at high pressure 40-65MPa, heating current 30-55A, heating step is the synthetic PCD superhard material that contains wild phase under the synthesis condition of 30-35MPa;
E, post processing: the PCD superhard material that contains wild phase obtaining is carried out to post processing.
In the present invention, strengthening core superhard material is cubic boron nitride c-BN, cube boron carbonitrides c-BC
2n, boron carbide B
4one or more in C or nano twin crystal cubic boron nitride nt-CBN.
3, the preparation method who contains the polycrystalline diamond ultra-hard abrasive material that strengthens core as claimed in claim 1, is characterized in that, the weight content of impurities from diamond micro powder is less than 1 ‰.
In the present invention, strengthen stem stem body and imbed diadust compound and make to strengthen stem stem body and have more than 70% surface area under diadust compound parcel.
In the present invention, the time of vacuum reduction is greater than 24h.
In the present invention, described post processing is pickling after pickling or ball milling.
In the present invention, the cross section of described enhancing stem stem body is circular, square or triangle.
Beneficial effect of the present invention is: novel super-hard wearing composite material prepared by the present invention, combine toughness two specific characters that superhard limiting material is similar to ultrahigh hardness and the glomerocryst material of natural diamond, having widened the range of application of superhard limiting material and glomerocryst material PCD, is also that the present situation that machine-building and oil, geological prospecting industry day by day improve ultra-hard abrasive material performance requirement provides a kind of settling mode.
Accompanying drawing explanation
Fig. 1 is that a kind of outer wrapping body shell is the columniform wear-resisting superhard material of PCD containing strengthening core.
Reference numeral: 1 for strengthening stem stem body; 2 is outer inclusion enclave, i.e. PCD.
The specific embodiment
embodiment 1:
1, utilize laser cutting machine that cubic boron nitride is cut into the little square column of 1 × 1 × 4mm.
2, screening diadust, according to 325-400 order, 460-700 order, 700-1200 order, 1200-1800 order, there is respectively the ratio of 8 parts, 8 parts, 70 parts, 10 parts to carry out proportioning, the ratio that is 1:20 than the mass ratio of powder gross mass according to bonding agent adds bonding agent to mix in diadust, after mixing, pack circular hole aperture Φ=3mm into, in the porous graphite post of high h=5mm.1 cubic boron nitride pillar is inserted in diamond powder, make under the encirclement completely of cubic boron nitride pillar in diamond powder.Ready material is put into vacuum reduction stove and reduce 48h.
3, putting into pyrophyllite block through the porous graphite post of vacuum reduction processing, assemble, the pyrophyllite block assembling is put into hinge type cubic hinge press.After press pressure rises to 30MPa, start heating, reduce heating current keep 35s under heating current 55A after and maintain 60s to 35A.
4, will carry out ball milling through the synthetic sintered product mixing carbide alloy bead of HTHP, after ball milling, pickling obtains containing cubic boron nitride and strengthens the wear-resisting superhard material of core PCD.
embodiment 2:
1, utilize laser cutting machine that a cube boron carbonitrides is cut into φ 1 × 5mm small column.
2, screening diadust, according to 325-400 order, 460-700 order, 700-1200 order, 1200-1800 order, there is respectively the ratio of 15 parts, 20 parts, 50 parts, 30 parts to carry out proportioning, the ratio that is 1:20 than the mass ratio of powder gross mass according to bonding agent adds bonding agent to mix in diadust, after mixing, pack circular hole aperture Φ=3mm into, in the porous graphite post of high h=6mm.1 cube of boron carbonitrides pillar is inserted in diamond powder, make under the encirclement completely of cube boron carbonitrides pillar in diamond powder.Ready material is put into vacuum reduction stove reductase 12 4h.
3, putting into pyrophyllite block through the porous graphite post of vacuum reduction processing, assemble, the pyrophyllite block assembling is put into hinge type cubic hinge press.After press pressure rises to 35MPa, start heating, reduce heating current keep 30s under heating current 50A after and maintain 65s to 30A.
4, will carry out ball milling through the synthetic sintered product mixing carbide alloy bead of HTHP, after ball milling, pickling obtains containing the wear-resisting superhard material of the strong core PCD of cube boron carbonitrides.
embodiment 3:
1, utilize laser cutting machine that boron carbide is cut into the little square column of 1.2 × 1.2 × 4mm.
2, screening diadust, according to 325-400 order, 460-700 order, 700-1200 order, 1200-1800 order, there is respectively the ratio of 10 parts, 15 parts, 65 parts, 10 parts to carry out proportioning, the ratio that is 1:5 than the mass ratio of powder gross mass according to bonding agent, after mixing, pack square hole hole limit l=2mm into, in the porous graphite post of high h=5mm.1 boron carbide cylinder is inserted in diamond powder, make under the encirclement completely of boron carbide cylinder in diamond powder.Ready material is put into vacuum reduction stove and reduce 36h.
3, putting into pyrophyllite block through the porous graphite post of vacuum reduction processing, assemble, the pyrophyllite block assembling is put into hinge type cubic hinge press.After press pressure rises to 30MPa, start heating, reduce heating current keep 35s under heating current 50A after and maintain 70s to 35A.
4, will carry out ball milling through the synthetic sintered product mixing carbide alloy bead of HTHP, after ball milling, pickling obtains containing boron carbide and strengthens the wear-resisting superhard material of core PCD.
embodiment 4:
1, utilize laser cutting machine that nano twin crystal cubic boron nitride is cut into the length of side for 1.2mm, height is the tri-prismoid of 4mm.
2, screening diadust, according to 325-400 order, 460-700 order, 700-1200 order, 1200-1800 order, there is respectively the ratio of 12 parts, 18 parts, 50 parts, 20 parts to carry out proportioning, the ratio that is 1:10 than the mass ratio of powder gross mass according to bonding agent, after mixing, pack circular hole aperture Φ=3mm into, in the porous graphite post of high h=6mm.2 nano twin crystal cubic boron nitride pillar interval 0.5mm are inserted to diamond powder central authorities, make under the encirclement completely of nano twin crystal cubic boron nitride pillar in diamond powder.Ready material is put into vacuum reduction stove reductase 12 4h.
3, putting into pyrophyllite block through the porous graphite post of vacuum reduction processing, assemble, the pyrophyllite block assembling is put into hinge type cubic hinge press.After press pressure rises to 33MPa, start heating, reduce heating current keep 30s under heating current 52A after and maintain 60s to 33A.
4, will carry out ball milling through the synthetic sintered product mixing carbide alloy bead of HTHP, after ball milling, pickling obtains containing nano twin crystal cubic boron nitride and strengthens the wear-resisting superhard material of core PCD.
embodiment 5:
1, utilize laser cutting machine that nano twin crystal cubic boron nitride is cut into φ 1 × 4mm small column.Utilize laser cutting machine that a cube boron carbonitrides is cut into φ 1 × 5mm small column.
2, screening diadust, according to 325-400 order, 460-700 order, 700-1200 order, 1200-1800 order, there is respectively the ratio of 15 parts, 8 parts, 65 parts, 12 parts to carry out proportioning, the ratio that is 1:15 than the mass ratio of powder gross mass according to bonding agent, after mixing, pack circular hole aperture Φ=3mm into, in the porous graphite post of high h=6mm.1 nano twin crystal cubic boron nitride pillar and 1 cube of boron carbonitrides pillar interval 0.5mm are inserted to diamond powder central authorities, make under the encirclement completely of nano twin crystal cubic boron nitride pillar in diamond powder.Ready material is put into vacuum reduction stove reductase 12 4h.
3, putting into pyrophyllite block through the porous graphite post of vacuum reduction processing, assemble, the pyrophyllite block assembling is put into hinge type cubic hinge press.After press pressure rises to 30MPa, start heating, reduce heating current keep 45s under heating current 55A after and maintain 70s to 36A.
4, will carry out ball milling through the synthetic sintered product mixing carbide alloy bead of HTHP, after ball milling, pickling obtains containing nano twin crystal cubic boron nitride and strengthens the wear-resisting superhard material of core PCD.
Finally it should be noted that: obviously, above-described embodiment is only for example of the present invention is clearly described, and the not restriction to embodiment.For those of ordinary skill in the field, can also make other changes in different forms on the basis of the above description.Here without also giving exhaustive to all embodiments.And the apparent variation of being amplified out thus or variation are still among protection scope of the present invention.
Claims (7)
1. a preparation method who contains the polycrystalline diamond ultra-hard abrasive material that strengthens core, is characterized in that, described method comprises the following steps:
A, prepare superhard material and strengthen core: adopt laser cutting technique that enhancings core superhard material is cut into enhancing stem stem body;
B, screening diadust: in diadust, 325-460 order accounts for 8-15 part, and 460-700 order accounts for 8-20 part, and 700-1200 order accounts for 50-70 part, and 1200-1800 order accounts for 10-30 part;
C, pressed by powder: in bonding agent, than the mass ratio of powder gross mass, be 1:(5-20) ratio in diadust, add bonding agent to mix, and compound is packed in porous graphite post, one or more are strengthened to stem stem body and imbed in diadust compound, vacuum reduction;
D, synthetic: porous graphite post is put into pyrophyllite block and assemble, the pyrophyllite block that assembling is completed is put into press, at high pressure 40-65MPa, heating current 30-55A, heating step is the synthetic PCD superhard material that contains wild phase under the synthesis condition of 30-35MPa;
E, post processing: the PCD superhard material that contains wild phase obtaining is carried out to post processing.
2. the preparation method who contains the polycrystalline diamond ultra-hard abrasive material that strengthens core as claimed in claim 1, is characterized in that, strengthening core superhard material is cubic boron nitride c-BN, cube boron carbonitrides c-BC
2n, boron carbide B
4one or more in C or nano twin crystal cubic boron nitride nt-CBN.
3. the preparation method who contains the polycrystalline diamond ultra-hard abrasive material that strengthens core as claimed in claim 1, is characterized in that, the weight content of impurities from diamond micro powder is less than 1 ‰.
4. the preparation method who contains the polycrystalline diamond ultra-hard abrasive material that strengthens core as claimed in claim 1, it is characterized in that, strengthen stem stem body and imbed diadust compound and make to strengthen stem stem body and have more than 70% surface area under diadust compound parcel.
5. the preparation method who contains the polycrystalline diamond ultra-hard abrasive material that strengthens core as claimed in claim 1, is characterized in that, the time of vacuum reduction is greater than 24h.
6. the preparation method who contains the polycrystalline diamond ultra-hard abrasive material that strengthens core as claimed in claim 1, is characterized in that, described post processing is pickling after pickling or ball milling.
7. the preparation method who contains the polycrystalline diamond ultra-hard abrasive material that strengthens core as described in claim 1-6 arbitrary, is characterized in that, the cross section of described enhancing stem stem body is circular, square or triangle.
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| CN104759240A (en) * | 2015-04-14 | 2015-07-08 | 四川大学 | Diamond-cubic boron nitride type universal superhard cutter material, cutter and preparation method of material |
| CN105797648A (en) * | 2016-03-25 | 2016-07-27 | 河南四方达超硬材料股份有限公司 | Manufacturing method of special-shaped hole polycrystalline diamond die blank |
| CN105859300A (en) * | 2016-04-05 | 2016-08-17 | 吉林师范大学 | Preparation method of diamond-cubic boron nitride-boron carbide composite material |
| CN107867016A (en) * | 2017-11-22 | 2018-04-03 | 深圳先进技术研究院 | A kind of composite polycrystal-diamond and preparation method thereof |
| CN108276022A (en) * | 2018-01-11 | 2018-07-13 | 东台市港泰耐火材料有限公司 | A kind of high-strength GM-28 grades of insulating fire bricks and preparation method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
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