CN102296223A - Fine grain WC-based cemented carbide material and its preparation method - Google Patents

Abstract

A fine grain WC-based cemented carbide material and its preparation method. According to the fine grain WC-based cemented carbide material; the fine grain WC is used as a matrix; Mo or Ni is used as a binder; one or more components selected from TaC, VC and TiC is used as a crystal grain inhibitor; Cr3C2 is used as a hardening agent; and C, SiC OR rare earth metal is used as a flexibilizer. The size of the fine crystal grain WC is 0.8-1 microns. Due to the size of the WC, the hardness and bending strength can be raised. The cemented carbide material provides a substitute for Co, and has high hardness, good toughness and excellent comprehensive wear resistant performance.

Description

A kind of close grain WC based hard alloy material and preparation method thereof

Technical field

The present invention relates to the field of Wimet, relate in particular to a kind of close grain WC based hard alloy material and preparation method thereof.

Background technology

Along with improving constantly of human living standard, demand to resource also constantly increases, and the operating cost of resource and further the difficulty the rock stratum in open up the new problem of being brought, brought the opposing of drilling tools has been broken and the more and more higher requirements of each side such as intensity, toughness and wear resistance of repeated stress failure, thus, need exploitation not only to have high rigidity but also have high-intensity high-abrasive material and new parts, new facility, adapt to the use under the extreme condition, require the material of the novel high rigidity of low cost development, high strength, high tenacity and high abrasion.

A series of premium propertiess such as existing WC base cemented carbide has intensity and hardness height, wear resistance is good, red hardness is good, thermal expansivity is little, Young's modulus is high and chemical stability is good, it is widely used on the various golden Drilling machines.

Yet, the tradition Wimet has used a large amount of valuable strategic resource Co, aggravated the nervous situation of resource and environment, studying non-Co Wimet is an important directions of this area, both had important economic worth, also have strategic importance, simultaneously, the grain size of WC base is also brought influence to the bending strength and the toughness of Wimet.

And in order to save valuable strategic resource Co, people continually develop the extensive resource that can substitute it, and by research, metal M o, Ni etc. are higher at occurring in nature degree of distribution and reserves, and has better chemical stability than Co, the WC base cemented carbide that is obtained as the metal bonding phase with metals such as Mo, Ni also is expected to have good antioxidant property and corrosion resistance nature except that the common advantage with Wimet.

But, in the preparation process of these metals,, thereby when sintering, form micropore in mechanical milling process because crystalline distortion and reunion will take place their structure easily, cause the product density poor; Therefore, must adopt suitable ball-milling technology, sintering method and sintering schedule could obtain high performance WC-Mo (Ni) Hardmetal materials alternative.Simultaneously, compare, when use is done metal adhesive such as Mo, Ni etc., the quick growth (overgrowing) of WC grain takes place easily with the WC-Co Wimet; Must could effectively suppress the WC grain overgrowing by the kind and the adding proportion of choose reasonable grain inhibitor; Thereby improve the intensity of material.

And the size of crystal grain is brought the performance variation of Wimet equally, the appearance of nano material brings new direction for equally the development of Wimet, by research, find under the constant situation of other materials, the grain fineness number of WC is from less than 1 μ m, its bending strength also is improved under the situation that hardness improves, and along with the further refinement of crystal grain, trend is more obvious.

Summary of the invention

The object of the present invention is to provide a kind of close grain WC based hard alloy material and preparation method thereof, the material of this Wimet provides substituting of Co, and hardness height, good toughness, has the excellent comprehensive wear resisting property.

For achieving the above object, the invention discloses a kind of close grain WC based hard alloy material, this close grain WC based hard alloy material has adopted compact grained WC as matrix, with Mo or Ni as binding agent, so that one or more are grain inhibitor among TaC, VC, the TiC, with Cr ₃C ₂As increasing hard agent, think that C, SiC or rare earth metal as toughner, is characterized in that:

The size of compact grained WC is 0.8-1 μ m, and this big or small WC can bring the raising of hardness and bending strength.

Wherein, the weight percent of material is as follows:

WC:85-86%, binding agent: 5-6%; Grain inhibitor: 7-8%; Toughener: 1%; Toughner: 1%.

Also disclose a kind of preparation method of close grain WC based hard alloy material, it is characterized in that, comprised following processing step:

1) preliminary working: take by weighing raw material by composition, raw material WC powder, binding agent powder, grain inhibitor powder and the toughener that takes by weighing in proportion added in the stirring ball-milling jar stir;

2) drying: in vacuum drying oven, the slurry after the preliminary working is carried out drying;

3) grind: the powder of oven dry is ground, grind the powder that the back forms the following aperture of 1mm;

4) charging: ground powder is put into sintering mold compress;

5) sintering: in sintering oven, carry out sintering, moulding, carry out sintering operation in the preferred Frequency Induction Heating sintering oven.

Wherein, churning time is 5-10 hour.

Wherein, drying conditions be 80～100 ℃, vacuum tightness 0～-0.33Pa under dry 6～10 hours.

By said structure, close grain WC based hard alloy material of the present invention and preparation method thereof has following technique effect:

(1) have bonding force preferably with matrix, the hardness that obtains is significantly improved, and intensity and toughness are maintained.

(2) owing to the effect of grain inhibitor and the employing of special sintering technology, sintering time is short, quick, helps improving simultaneously the strength of materials, toughness and hardness.

(3) owing to adopted close grain WC base, improve the intensity and the toughness of bonding phase, effectively improved the intensity and the fracture toughness property of Wimet.

(4) Novel WC-based hard alloy material of manufacturing has high hardness, intensity and toughness simultaneously, the comprehensive wear resisting property of material increases substantially, and material oxidation-resistance and excellent corrosion resistance, be expected to be used for novel load-carrying geological drilling facility, also can be used for high performance machine processing cutting tool, mould.

The present invention will further describe in detail by the following specific embodiments.

Embodiment

Below in conjunction with embodiment technical scheme of the present invention is further specified.

The present invention proposes a kind of close grain WC based hard alloy material and preparation method thereof, this close grain WC based hard alloy material has adopted compact grained WC as matrix, with Mo or Ni as binding agent, so that one or more are grain inhibitor among TaC, VC, the TiC, with Cr ₃C ₂As increasing hard agent, think that C, SiC or rare earth metal are as toughner.

Wherein preferably, the size of compact grained WC is 0.8-1 μ m, and this big or small WC can bring the raising of hardness and bending strength, and its cost can not increased substantially simultaneously.

Preferably, wherein the weight percent of material is as follows:

WC:85-86%, binding agent: 5-6%; Grain inhibitor: 7-8%; Toughener: 1%; Toughner: 1%.

Wherein, the described preparation method of close grain WC based hard alloy material of the present invention comprises following processing step and content:

1) preliminary working: take by weighing raw material by composition, raw material WC powder, binding agent powder, grain inhibitor powder and the toughener that takes by weighing in proportion added in the stirring ball-milling jar stir, churning time is preferably 5-10 hour;

2) drying: in vacuum drying oven, the slurry after the preliminary working is carried out drying, drying conditions preferably 80～100 ℃, vacuum tightness 0～-0.33Pa under dry 6～10 hours;

3) grind: the powder of oven dry is ground, grind the powder that the back forms the following aperture of 1mm;

4) charging: ground powder is put into sintering mold compress;

5) sintering: in sintering oven, carry out sintering, moulding, carry out sintering operation in the preferred Frequency Induction Heating sintering oven.

Embodiment 1:

The manufacture method and the technical process of the close grain WC base cemented carbide of the embodiment of the invention are as follows:

1) preliminary working: take by weighing raw material by composition, its raw material is:

0.9 the WC:85% of μ m, Mo:5%; TiC:8%; Cr ₃C ₂: 1%; Si:C1%;

To stir churning time 8 hours in the raw material adding stirring ball-milling jar that take by weighing in proportion;

2) drying: in vacuum drying oven, the slurry after the preliminary working is carried out drying, drying conditions is 90 ℃, vacuum tightness-0.2Pa dry 8 hours down;

3) grind: the powder of oven dry is ground, grind the powder that the back forms the following aperture of 1mm;

4) charging: ground powder is put into sintering mold compress;

5) sintering: in sintering oven, carry out sintering, moulding, carry out sintering operation in the preferred Frequency Induction Heating sintering oven.

The data of the close grain WC base cemented carbide that present embodiment 1 is prepared are as follows:

Hardness: 93HRA, flexural strength 3800N/mm ²HC:40KA/m.

Embodiment 2:

The manufacture method and the technical process of the close grain WC base cemented carbide of the embodiment of the invention are as follows:

1) preliminary working: take by weighing raw material by composition, its raw material is:

The WC:86% of 1 μ m, Ni:5%; VC:7%; Cr ₃C ₂: 1%; Si:C1%;

To stir churning time 8 hours in the raw material adding stirring ball-milling jar that take by weighing in proportion;

2) drying: in vacuum drying oven, the slurry after the preliminary working is carried out drying, drying conditions is 90 ℃, vacuum tightness-0.2Pa dry 8 hours down;

3) grind: the powder of oven dry is ground, grind the powder that the back forms the following aperture of 1mm;

4) charging: ground powder is put into sintering mold compress;

5) sintering: in sintering oven, carry out sintering, moulding, carry out sintering operation in the preferred Frequency Induction Heating sintering oven.

The data of the close grain WC base cemented carbide that present embodiment 1 is prepared are as follows:

Hardness: 95HRA, flexural strength 3700N/mm ²HC:39KA/m.

It is evident that above description and record only are for example rather than in order to limit disclosure of the present invention, application or use.Though described in an embodiment, but the present invention is not limited in optimal mode that the conduct described among the embodiment thinks at present implementing the specific examples of instruction of the present invention, and scope of the present invention will comprise any embodiment of the specification sheets that falls into the front and appended claim.

Claims (5)

1. close grain WC based hard alloy material, this close grain WC based hard alloy material has adopted compact grained WC as matrix, with Mo or Ni as binding agent, so that one or more are grain inhibitor among TaC, VC, the TiC, with Cr ₃C ₂As increasing hard agent, think that C, SiC or rare earth metal as toughner, is characterized in that:

The size of compact grained WC is 0.8-1 μ m, and this big or small WC can bring the raising of hardness and bending strength.

2. close grain WC based hard alloy material as claimed in claim 1 is characterized in that the weight percent of material is as follows:

WC:85-86%, binding agent: 5-6%; Grain inhibitor: 7-8%; Toughener: 1%; Toughner: 1%.

3. the preparation method of close grain WC based hard alloy material as claimed in claim 1 or 2 is characterized in that, comprises following processing step:

1) preliminary working: take by weighing raw material by composition, raw material WC powder, binding agent powder, grain inhibitor powder and the toughener that takes by weighing in proportion added in the stirring ball-milling jar stir;

2) drying: in vacuum drying oven, the slurry after the preliminary working is carried out drying;

3) grind: the powder of oven dry is ground, grind the powder that the back forms the following aperture of 1mm;

4) charging: ground powder is put into sintering mold compress;

5) sintering: in sintering oven, carry out sintering, moulding, carry out sintering operation in the preferred Frequency Induction Heating sintering oven.

4. preparation method as claimed in claim 3 is characterized in that, churning time is 5-10 hour.

5. preparation method as claimed in claim 3 is characterized in that, drying conditions be 80～100 ℃, vacuum tightness 0～-0.33Pa under dry 6～10 hours.