CN108101541A - A kind of ejection forming method of non-bond cemented carbide - Google Patents

A kind of ejection forming method of non-bond cemented carbide Download PDF

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Publication number
CN108101541A
CN108101541A CN201711388964.8A CN201711388964A CN108101541A CN 108101541 A CN108101541 A CN 108101541A CN 201711388964 A CN201711388964 A CN 201711388964A CN 108101541 A CN108101541 A CN 108101541A
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Prior art keywords
sintering
cemented carbide
powder
forming method
ejection forming
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周军州
李世鹏
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Luoyang Mingli Science and Technology Development Co Ltd
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Luoyang Mingli Science and Technology Development Co Ltd
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    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/515Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics
    • C04B35/56Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on carbides or oxycarbides
    • C04B35/5607Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on carbides or oxycarbides based on refractory metal carbides
    • C04B35/5626Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on carbides or oxycarbides based on refractory metal carbides based on tungsten carbides
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/64Burning or sintering processes
    • C04B35/645Pressure sintering
    • C04B35/6455Hot isostatic pressing
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30Constituents and secondary phases not being of a fibrous nature
    • C04B2235/38Non-oxide ceramic constituents or additives
    • C04B2235/3817Carbides
    • C04B2235/3839Refractory metal carbides
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30Constituents and secondary phases not being of a fibrous nature
    • C04B2235/38Non-oxide ceramic constituents or additives
    • C04B2235/3817Carbides
    • C04B2235/3839Refractory metal carbides
    • C04B2235/3843Titanium carbides
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/65Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
    • C04B2235/658Atmosphere during thermal treatment
    • C04B2235/6581Total pressure below 1 atmosphere, e.g. vacuum

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Powder Metallurgy (AREA)

Abstract

The present invention provides a kind of ejection forming methods of non-bond cemented carbide, mainly include the following steps that:Batch mixing:WC powder, TiC powder, TaC powder are weighed according to a certain percentage, carry out ball milling drying;It is kneaded:Mixture powder is kneaded with binding agent, and injection feeding is made;Feeding is extruded by banding, strip using extrusion device, is pelletized by pulverizer;Injection moulding:Feeding is passed through into injector injection moulding;Degreasing:Including solvent degreasing and thermal debinding;Vacuum-sintering:Vacuum-sintering is taken to carry out at a certain temperature pre-sintered;HIP sintering:Green body after pre-sintering, which is put into hot isostatic pressing stove, carries out HIP sintering promotion densification.The technology of the present invention can obtain the non-bond cemented carbide product of various complicated shapes by injection molding process, and for material density up to 99.9%, technological process is simple, and raw material availability is high, is suitble to industrialization production.

Description

A kind of ejection forming method of non-bond cemented carbide
Technical field
The present invention relates to hard alloy preparing technical field more particularly to a kind of injection mouldings of non-bond cemented carbide Method.
Background technology
Hard alloy has high rigidity, high-wearing feature, good chemical stability and thermal stability, is widely used in the modern times Tool materials, wear-resistant material, heat-resisting material, resistant material etc..General hard alloy be by hard phase (based on WC) and Binder Phase (iron group metal) is formed.Non-bond cemented carbide is a kind of cemented carbide material without Binder Phase, is had excellent Mechanical property and corrosion resistance, be mainly used in the application field of requirement highly corrosion resistant and high-wearing feature.
Injection molding technology is a kind of near-net-shape technology, can manufacture complex-shaped, dimension precision requirement is high, high-volume The product of production, even density, respectively identical, similar to hot investment casting to shrinking, and precision and surface roughness are good, without after Continuous processing.Non-bond cemented carbide is prepared using injection molding technology, the production that can meet various complicated shape structural members will It asks, raw material availability is high, at low cost, is suitble to industrialization production.
Non-bond cemented carbide sintering densification is relatively difficult, is difficult to obtain densification production using conventional sintering process Product.It is handled by HIP sintering, most of micro-pore in product can be eliminated, high densification product is obtained, be conducive to It enhances product performance.
The content of the invention
To solve the above problems, the technical solution adopted is that:
A kind of ejection forming method of non-bond cemented carbide, includes the following steps:
(1) batch mixing:WC powder, TiC powder, TaC powder are weighed according to a certain percentage, are put into ball grinding cylinder, add in mill Jie's ball and Decentralized medium, ball milling take out and dry sieving afterwards for a period of time;
(2) it is kneaded:Mixture powder and binding agent are weighed according to a certain percentage, is added in kneading machine, is heated and be kneaded For a period of time;
(3) pelletize:Feeding is extruded by banding, strip using extrusion device, is pelletized by pulverizer;
(4) injection moulding:Feeding after granulation is injected into variously-shaped injection base using injector;
(5) degreasing:Remove portion of binder in a solvent first, then the remaining binding agent of heating removing;
(6) vacuum-sintering:Vacuum-sintering is taken to carry out at a certain temperature pre-sintered;
(7) HIP sintering:Green body after pre-sintering, which is put into hot isostatic pressing stove, carries out HIP sintering promotion cause Densification.
The object of the invention to solve the technical problems also can be used following technical measures and further realize:
A kind of ejection forming method of foregoing non-bond cemented carbide, wherein, the mass fraction of powder is:WC powder 93 ~96%, TiC powder 2~4%, TaC powder 1~3%.
A kind of ejection forming method of foregoing non-bond cemented carbide, wherein, mill Jie ball during ball milling is that hard closes Gold goal, decentralized medium are acetone;Ball material weight ratio is 3:1, solid-liquid volume ratio is 1:5, Ball-milling Time is 50~80h.
A kind of ejection forming method of foregoing non-bond cemented carbide, wherein, the quality of the mixing binding agent Fraction is:Paraffin 30~40%, beeswax 30~40%, polyethylene 20~40% and stearic acid 2~10%;Mixture powder Volume fraction is 50~65%.
A kind of ejection forming method of foregoing non-bond cemented carbide, wherein, melting temperature is 120~180 DEG C, is mixed The refining time is 2~6h.
A kind of ejection forming method of foregoing non-bond cemented carbide, wherein, injection temperature is 160~180 DEG C, note Injection pressure is 60~80MPa, and mould temperature is 25-35 DEG C.
A kind of ejection forming method of foregoing non-bond cemented carbide, wherein, solvent degreasing can be selected trichloro ethylene, One kind in chloroform or normal heptane, skimming temp are 45~70 DEG C, and degreasing time is 5~8h;Thermal debinding temperature for 450~ 500℃。
A kind of ejection forming method of foregoing non-bond cemented carbide, wherein, the sintering temperature of vacuum-sintering is 1600~1700 DEG C, soaking time is 40~90min.
A kind of ejection forming method of foregoing non-bond cemented carbide, wherein, the sintering temperature of HIP sintering For 1400~1500 DEG C, pressure is 80~150MPa, and soaking time is 40~90min.
Compared with prior art, the present invention can be prepared complex-shaped product, be obtained high cause using injection molding technology Close or even fully dense non-bond cemented carbide product, raw material availability is high, is suitble to produce in enormous quantities.
Above description is only the general introduction of technical solution of the present invention, in order to better understand the technological means of the present invention, And can be practiced according to the content of specification, and in order to allow the present invention above-mentioned advantage and other purposes, feature and advantage It can be clearer and more comprehensible, special below to lift preferred embodiment, detailed description are as follows.
Description of the drawings
Nothing
Specific embodiment
Embodiment 1:
A kind of ejection forming method of non-bond cemented carbide, includes the following steps:
(1) batch mixing:It weighs 93%WC powder, 3%TiC powder, 3%TaC powder to be put into ball grinding cylinder, adds in hard alloy mill Jie's ball With acetone decentralized medium.Add in 3% paraffin binder of powder raw material, ratio of grinding media to material 3:1 (weight ratio), solid-to-liquid ratio 1:5 (volume ratio), Ball-milling Time 72h take out after ball milling and dry sieving;
(2) it is kneaded:Mixture powder and binding agent are weighed according to a certain percentage, the volume fraction of mixture powder is 55%, it adds in kneading machine.33% paraffin of Binder Composition, 33% beeswax, 30% polyethylene and 4% stearic acid form compound Binding agent.Melting temperature is 150 DEG C, is kneaded 4h;
(3) pelletize:Feeding is extruded into respectively three times by banding, strip using extrusion device, is pelletized by pulverizer;
(4) injection moulding:Feeding after granulation is injected into variously-shaped injection base using injector.Injection temperature is 160 DEG C, injection pressure 75MPa, mould temperature is 30 DEG C or so;
(5) degreasing:Using two step degreasing methods of solvent degreasing+thermal debinding.Part is removed in trichloroethylene solvent first Binding agent, temperature are 50 DEG C, time 6h.Then the thermal debinding in dewaxing furnace, thermal debinding temperature are 500 DEG C, and heating removing is surplus Remaining binding agent;
(6) vacuum-sintering:Vacuum sintering method is taken to carry out pre-sintered, vacuum-sintering temperature is 1650 DEG C, soaking time For 60min;
(7) HIP sintering:Green body after pre-sintering, which is put into hot isostatic pressing stove, carries out HIP sintering promotion cause Densification, the sintering temperature of HIP sintering is 1450 DEG C, pressure 100MPa, soaking time 40min.
Embodiment 2:
A kind of ejection forming method of non-bond cemented carbide, includes the following steps:
(1) batch mixing:It weighs 94.5%WC powder, 3%TiC powder, 2.5%TaC powder to be put into ball grinding cylinder, adds in hard alloy mill Jie's ball and acetone decentralized medium.Add in 3% paraffin binder of powder raw material, ratio of grinding media to material 3:1 (weight ratio), solid-to-liquid ratio are 1:5 (volume ratios), Ball-milling Time 72h take out after ball milling and dry sieving;
(2) it is kneaded:Mixture powder and binding agent are weighed according to a certain percentage, the volume fraction of mixture powder is 60%, it adds in kneading machine.41% paraffin of Binder Composition, 32% beeswax, 22% polyethylene and 5% stearic acid form compound Binding agent.Melting temperature is 150 DEG C, is kneaded 6h;
(3) pelletize:Feeding is extruded into respectively three times by banding, strip using extrusion device, is pelletized by pulverizer;
(4) injection moulding:Feeding after granulation is injected into variously-shaped injection base using injector.Injection temperature is 160 DEG C, injection pressure 75MPa, mould temperature is 30 DEG C or so;
(5) degreasing:Using two step degreasing methods of solvent degreasing+thermal debinding.Part is removed in trichloroethylene solvent first Binding agent, temperature are 50 DEG C, time 6h.Then the thermal debinding in dewaxing furnace, thermal debinding temperature are 500 DEG C, and heating removing is surplus Remaining binding agent;
(6) vacuum-sintering:Vacuum sintering method is taken to carry out pre-sintered, vacuum-sintering temperature is 1650 DEG C, soaking time For 60min;
(7) HIP sintering:Green body after pre-sintering, which is put into hot isostatic pressing stove, carries out HIP sintering promotion cause Densification, the sintering temperature of HIP sintering is 1430 DEG C, pressure 120MPa, soaking time 60min.
The above described is only a preferred embodiment of the present invention, not doing limitation in any form to the present invention, appoint What those skilled in the art, without departing from the scope of the present invention, is made a little using above-mentioned technology contents It changes or the embodiment of modification, in the range of still falling within technical solution of the present invention.

Claims (9)

1. a kind of ejection forming method of non-bond cemented carbide, it is characterised in that:Include the following steps:
Batch mixing:WC powder, TiC powder, TaC powder are weighed according to a certain percentage, are put into ball grinding cylinder, adds in mill Jie's ball and scattered Jie Matter, ball milling take out and dry sieving afterwards for a period of time;
It is kneaded:Mixture powder and binding agent are weighed according to a certain percentage, added in kneading machine, when heating and being kneaded one section Between;
Granulation:Feeding is extruded by banding, strip using extrusion device, is pelletized by pulverizer;
Injection moulding:Feeding after granulation is injected into variously-shaped injection base using injector;
Degreasing:Remove portion of binder in a solvent first, then the remaining binding agent of heating removing;
Vacuum-sintering:Vacuum-sintering is taken to carry out at a certain temperature pre-sintered;
HIP sintering:Green body after pre-sintering, which is put into hot isostatic pressing stove, carries out HIP sintering promotion densification.
2. a kind of ejection forming method of non-bond cemented carbide as described in claim 1, it is characterised in that:The matter of powder Measuring fraction is:WC powder 93~96%, TiC powder 2~4%, TaC powder 1~3%.
3. a kind of ejection forming method of non-bond cemented carbide as described in claim 1, it is characterised in that:During ball milling It is sintered carbide ball to grind Jie's ball, and decentralized medium is acetone;Ball material weight ratio is 3:1, solid-liquid volume ratio is 1:5, Ball-milling Time is 50~80h.
4. a kind of preparation method of non-bond cemented carbide as described in claim 1, which is characterized in that the mixing is glued Knot agent mass fraction be:Paraffin 30~40%, beeswax 30~40%, polyethylene 20~40% and stearic acid 2~10%;It is mixed The volume fraction for closing feed powder end is 50~65%.
5. a kind of ejection forming method of non-bond cemented carbide as described in claim 1, it is characterised in that:Melting temperature For 120~180 DEG C, mixing time is 2~6h.
6. a kind of ejection forming method of non-bond cemented carbide as described in claim 1, it is characterised in that:Injection temperature For 160~180 DEG C, injection pressure is 60~80MPa, and mould temperature is 25-35 DEG C.
7. a kind of ejection forming method of non-bond cemented carbide as described in claim 1, it is characterised in that:Solvent degreasing One kind in trichloro ethylene, chloroform or normal heptane can be selected, skimming temp is 45~70 DEG C, and degreasing time is 5~8h;Heat Skimming temp is 450~500 DEG C.
A kind of 8. ejection forming method of non-bond cemented carbide as described in claim 1, which is characterized in that vacuum-sintering Sintering temperature for 1600~1700 DEG C, soaking time is 40~90min.
9. a kind of ejection forming method of non-bond cemented carbide as described in claim 1, it is characterised in that:Hot isostatic pressing The sintering temperature of sintering is 1400~1500 DEG C, and pressure is 80~150MPa, and soaking time is 40~90min.
CN201711388964.8A 2017-12-21 2017-12-21 A kind of ejection forming method of non-bond cemented carbide Pending CN108101541A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110181059A (en) * 2018-12-13 2019-08-30 苏州赛特锐精密机械配件有限公司 A kind of method of co-injection near-net-shape ultra-fine cemented carbide cutter green body
CN111673089A (en) * 2020-05-18 2020-09-18 株洲天成金属激光高科有限公司 Hard alloy vertical needle injection molding process for microwave chip packaging
CN117020204A (en) * 2023-08-22 2023-11-10 钢研昊普科技有限公司 20CrNiMo bearing piece and preparation method and application thereof

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101423901A (en) * 2007-10-29 2009-05-06 比亚迪股份有限公司 Method for preparing cermet material
CN102296223A (en) * 2011-08-15 2011-12-28 四川欧曼机械有限公司 Fine grain WC-based cemented carbide material and its preparation method
CN105290404A (en) * 2015-09-29 2016-02-03 洛阳暖盈电子技术有限公司 Preparation method for hard alloy products by injection molding
CN107459353A (en) * 2017-07-04 2017-12-12 江苏大学 A kind of method of VC, TiC enhancing soap-free emulsion polymeization phase WC base cemented carbide performances

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101423901A (en) * 2007-10-29 2009-05-06 比亚迪股份有限公司 Method for preparing cermet material
CN102296223A (en) * 2011-08-15 2011-12-28 四川欧曼机械有限公司 Fine grain WC-based cemented carbide material and its preparation method
CN105290404A (en) * 2015-09-29 2016-02-03 洛阳暖盈电子技术有限公司 Preparation method for hard alloy products by injection molding
CN107459353A (en) * 2017-07-04 2017-12-12 江苏大学 A kind of method of VC, TiC enhancing soap-free emulsion polymeization phase WC base cemented carbide performances

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110181059A (en) * 2018-12-13 2019-08-30 苏州赛特锐精密机械配件有限公司 A kind of method of co-injection near-net-shape ultra-fine cemented carbide cutter green body
CN111673089A (en) * 2020-05-18 2020-09-18 株洲天成金属激光高科有限公司 Hard alloy vertical needle injection molding process for microwave chip packaging
CN117020204A (en) * 2023-08-22 2023-11-10 钢研昊普科技有限公司 20CrNiMo bearing piece and preparation method and application thereof

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Application publication date: 20180601