RU2286243C1 - Bond for manufacture of diamond tools - Google Patents

Abstract

FIELD: powder metallurgy; manufacture of diamond tools for construction engineering and treatment of stones.

SUBSTANCE: proposed bond contains nickel and alloying additive in form of nano-powder; content of alloying additive is <1.6 or ≤15 mass-%. Used as alloying additive is tungsten carbide or tungsten or aluminum oxide or zirconium dioxide or niobium carbide or ultra-dispersed diamonds coated with silver or nickel.

EFFECT: enhanced wear resistance with no increase of sintering temperature, hardness, strength and impact viscosity.

3 cl, 1 tbl

Description

The invention relates to powder metallurgy, to methods for producing products from carbide materials. The invention can be used as nickel-based bundles in the manufacture of diamond cutting tools for the construction industry and stone processing, including cutting segment wheels (AOSK) of various designs and ropes for cutting reinforced concrete and asphalt used in the reconstruction of highways, runways of airports, renovations metallurgical enterprises, nuclear power plants, bridges and other structures; drills for cutting reinforced concrete; disks and ropes for quarrying of natural stone and large-scale production of facing materials.

The bundle affects the design of the tool. Depending on the bond, the material of the casing is selected, the method of connecting the diamond layer with the casing. The physicomechanical properties of the ligaments predetermine the possible resulting shape and dimensions of the diamond-abrasive tool.

Known binder for the manufacture of diamond tools (RU 2172238 C2, published. 2001.08.20, CL B 24 D 3/06), containing a base in the form of copper and additives in the form of tin, nickel, aluminum and ultrafine diamond.

A disadvantage of the known material is insufficient wear resistance, hardness, strength and toughness.

A prototype of the claimed invention is a bond for abrasive material, comprising more than 40%, the weight of Nickel and alloying additives (JP 2972623 B2, published. 05.02.02).

A disadvantage of the known ligament is also insufficient hardness and strength.

The invention achieves the technical result, which consists in increasing wear resistance without a significant increase in sintering temperature, as well as hardness, strength and toughness.

The specified technical result is achieved as follows.

The diamond tool binder contains nickel and a dopant in the form of a nanopowder. The content in the binder of the dopant is 1-15 wt.%.

In this case, tungsten carbide, or tungsten, or aluminum oxide, or zirconia, or niobium carbide is used as an alloying additive.

Also, ultrafine diamonds coated with silver or nickel are used as an alloying additive.

Due to the presence of nickel as the main component of the composition, the bond meets the following requirements:

a) has good wettability with respect to diamond;

b) firmly holds diamond grains;

c) provides self-sharpening, i.e. as the blunting of the diamond grains, it wears out, contributing to the chipping of the blunt grains and the opening of the cutting faces of the new grains;

g) has sufficient heat resistance and has good thermal conductivity;

d) paired with the processed material has a minimum coefficient of friction;

e) has a coefficient of linear expansion, approaching the coefficient of linear expansion of diamond;

g) does not enter into chemical interaction with the processed material and coolant.

Due to the presence of nickel as the main component of the composition, the bond meets the following requirements

Alloying additives of the specified composition provide high hardness, heat resistance and heat resistance of the ligaments.

The content of alloying additives in an amount below the minimum value of the specified range (1 wt.%) Is not sufficient to ensure uniform distribution throughout the volume of the material and their effect on the structure and properties of the resulting material is negligible. When exceeding the maximum value of the range (15 wt.%), The content of the alloying material - the nanocomponent is too high. Since the alloying material is a harder material than nickel, it acts as a stress concentrator, which greatly embrittles the material and leads to a decrease in the strength characteristics and wear resistance of the binder.

Bundles can be obtained by powder metallurgy: sintering followed by pressing at a sintering temperature. This method is highly efficient, since the duration of the heating process to sintering temperature, holding at sintering temperature, pressing and cooling to room temperature do not exceed 15 minutes. High heating rates and a uniform temperature distribution in the working chamber are ensured by passing an electric current through a sinter mold, which is also a mold. At the end of the exposure at the annealing temperature, pressing is immediately carried out to ensure the necessary density and shape of the products. The mold design allows the process to be carried out in an inert or protective atmosphere, which improves the quality of the tool.

The table shows examples showing the dependence of the composition of the ligaments and the resulting properties.

Table Composition, wt.% Rockwell Hardness, 1.5 / 980 Flexural strength σ ^mfd, MPa Impact strength, KCU, J / cm ² 100% Ni _Bundle (B13) 88 920 3.36 99.3% Ni _bond + 07% dopant (Al ₂ O ₃ , or WC, or W, or ZrO ₂ , or NbC, or C _{diamond UDP} + Ni, or C _{diamond UDP} + Ag) 93 919 3.37 99% Ni _bond + 1.0% dopant (Al ₂ O ₃ , or WC, or W, or 98 1198 3.80 ZrO ₂ , or NbC, or C _{diamond UDP} + Ni or C _{diamond UDP} + Ag) 98% Ni _bond + 2.0% dopant (Al ₂ O ₃ , or WC, or W, or ZrO ₂ , or NbC, or C _{diamond UDP} + Ni, or C _{diamond UDP} + Ag) 101 1200 3.90 90% Ni _bond + 10.0% dopant (Al ₂ О ₃ , or WC, or W, or ZrO ₂ , or NbC, or С _{diamond udp} + Ni, or С _{diamond УДП} + Ag) 104 1250 4.04 85% Ni _bond + 15.0% dopant (Al ₂ O ₃ , or WC, or W, or ZrO ₂ , or NbC, or C _{diamond UDP} + Ni, or C _{diamond UDP} + Ag) 102 1200 4.00 80% Ni _bond + 20.0% dopant (Al ₂ O ₃ , or WC, or W, or ZrO ₂ , or NbC, or C _{diamond UDP} + Ni, or C _{diamond UDP} + Ag) 102 1190 3.87 78% Ni _bond + 22.0% dopant (Al ₂ O ₃ , or WC, or W, or ZrO ₂ , or NbC, or C _{diamond UDP} + Ni, or C _{diamond UDP} + Ag) 92 953 3.01

The materials of the ligaments according to the invention will provide better economic indicators in comparison with analogues of the world's leading manufacturers according to the criteria of price / resource and price / performance. For example, diamond-containing segments for cutting asphalt operate in a superhard abrasive medium. The traditional matrix hardening due to the introduction of tungsten carbide has a concentration limit due to the need to increase the sintering temperature (this means a decrease in diamond strength and additional wear of technological equipment).

The introduction of alloying additives - nanoparticles into the binder will increase its wear resistance without a significant increase in sintering temperature. Granite cutting segments are involved in the mass production of building cladding materials and therefore are themselves a mass product. The cost of their manufacture and unit operating costs play an important role in the economy of the corresponding production. Replacing traditional high-cobalt binders with nickel-based ones will reduce the corresponding raw material costs. In this case, the service characteristics (wear resistance, hardness, toughness) of such ligaments will be preserved by the introduction of WC, Al ₂ O ₃ and other nanoparticles into them. Materials used as ligaments for the manufacture of perlins, suitable for hot pressing, have largely come to the limit in official characteristics.

Further development follows the path of hot isostatic pressing (GUI) technology, which requires very high capital costs for equipment worth several million dollars. On the other hand, by hot pressing due to the introduction of nanoparticles into the bundle, it is possible to produce perlins with characteristics similar to those obtained using the HIP technology.

The introduction of alloying additives - nanopowders of tungsten carbide, or tungsten, or aluminum oxide, or zirconium dioxide, or niobium carbide - provides high strength, thermal conductivity and crack resistance. Controlled small additives of alloying elements give a unique combination of properties: strength, hardness, crack resistance, coefficient of friction in the cutting zone, which allows to increase the service life of products in especially loaded conditions by 10-20% relative to the base case while maintaining the cutting ability. Replacing cobalt ligaments with cheaper ones based on nickel and iron will reduce production costs by 15-20%.

Claims (3)

1. A bunch for the manufacture of diamond tools containing nickel and a dopant (LD) in the form of a nanopowder, while the content in a bunch of dopant is 1.6 <LD ≤15 wt.%, 2. The bond according to claim 1, in which tungsten carbide, or tungsten, or aluminum oxide, or zirconia, or niobium carbide is used as an alloying additive. 3. The bond according to claim 1, in which ultrafine diamonds coated with silver or nickel are used as a dopant.