RU2424889C1 - Mass for production of diamond abrasive wheel - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to abrasive processing and may be used in production of diamond abrasive wheels on organic binder for processing of oxide ceramic materials. Diamond tool is made from mass containing diamond, abrasive filler and polymer binder. Abrasive filler represents boron carbide or alundum. Additionally, said mass contains silicon carbide and solid antifriction filler in the following ratio of components, in wt %, diamond - 12.5-37.5; boron carbine or alundum - 1.0-20.0; silicon carbide - 5.0-40.0; solid antifriction filler - 0.5-5.0, polymer binder making the rest.

EFFECT: optimum hardness and cutting performances, better heat removal from processing zone.

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Description

The invention relates to the production of grinding tools, in particular the production of diamond wheels on an organic bond for processing materials such as oxide ceramics.

Known masses for the manufacture of diamond wheels containing diamond powder, resin and fillers: silicon carbide and antifriction material, such as molybdenum disulfide, graphite, etc. (US patent No. 3779727, CL 51-298, 1971, No. 3868232, K. 51-298, 1973, No. 4385907, class B24D 3/18, 1980) The disadvantage of grinding wheels made from these masses is that the wheels are ineffective in processing materials such as oxide ceramics and have low wear resistance.

Known mass for the manufacture of diamond tools containing diamond powder, boron carbide, copper, bakelite and a surface-active filler, such as cadmium (ed. St. No. 268231, CL S09K 3/14, 1968). The effect of the use of circles containing surface-active fillers in the working part occurs when grinding materials that have molecular affinity with the filler. When processing materials such as oxide ceramics, the use of such circles is ineffective.

The closest is the mass for the manufacture of diamond tools containing diamond powder, boron carbide, copper, cadmium, calcium hexaboride and pulverbakelite (ed. Certificate. No. 645830, class B24D 3/28, 1977). Circles made from this mass are used for machining hard alloys and alloy steels. When processing ceramic materials, especially low porosity, these wheels have a low cutting ability and, accordingly, low resistance, do not provide the necessary heat removal from the cutting zone and the required cleanliness of the processed surface.

The technical task is to create a diamond tool for processing materials such as oxide ceramics, characterized by optimal resistance and cutting ability, providing the necessary cleanliness of the treated surface and improved heat dissipation from the cutting zone.

The technical result is achieved by the fact that the mass for the manufacture of diamond tools containing diamond, abrasive filler and a polymeric binder, as an abrasive filler it contains boron carbide or electrocorundum, and additionally contains silicon carbide and a solid antifriction filler selected from the group: molybdenum disulfide, hexagonal boron nitride, graphite, in the following ratio of components, vol.%:

diamond - 12.5-37.5 boron carbide or electrocorundum - 1.0-20.0 silicon carbide - 5.0-40.0 solid anti-friction filler, hexagonal molybdenum disulfide boron nitride, graphite - 0.5-5.0 polymer binder - the rest

The grains of boron carbide and electrocorundum in the grinding tool play the role of a second abrasive material, providing, together with diamond grains, the main removal of the processed material. At the same time, these abrasive materials are distinguished by some fragility, which positively affects the cutting ability of the tool and its self-sharpening. However, when processing low-porous oxide ceramics, the introduced amount of boron carbide or electrocorundum is insufficient to ensure optimal tool performance.

Silicon carbide is more brittle and less hard than boron carbide and electrocorundum, so during grinding its grains are more easily destroyed, partially fall out of the binder, and thereby improve the tool’s self-sharpening. The destroyed silicon carbide grains remaining in the bunch are characterized by the presence of newly formed sharp cutting edges; such grains, being an abrasive material, improve the cutting ability of the tool, and since these grains are smaller, they contribute to an increase in the cleanliness of the processed surface.

It is known that silicon carbide has a relatively low heat capacity, and its thermal conductivity is high, but the amount of silicon carbide introduced does not completely remove heat from the cutting zone. Therefore, a solid anti-friction filler is introduced into the composition of the mass. As a solid antifriction filler, materials such as molybdenum disulfide, hexagonal boron nitride, and graphite can be introduced into the mass. However, other solid fillers can be used that do not impair the performance of the tool.

As the polymer binder, there may be, for example, a phenol-formaldehyde powder binder, which turns into a non-meltable and insoluble state when heated during the manufacturing of a diamond tool.

All components of the mass are included in its composition in such an amount as to provide the tool with the required cutting ability, with its high resistance, good heat dissipation from the cutting zone and to obtain a high grade of processing purity.

From the proposed mass were made grinding wheels of the following compositions, vol.%:

Diamond 12/5 25.0 37.5 Boron carbide, electrocorundum 20,0 8.0 1,0 Silicon carbide 40/0 16,0 5,0 Solid anti-friction 0.5 2/5 5,0 filler selected from groups: molybdenum disulfide, hexagonal boron nitride, graphite Polymer binder 27 48.5 51/5

Grinding wheels treated plates made of oxide ceramics, which were glued to the supporting surface. About 10,000 pieces were processed in circles from the proposed composition. plates. The cleanliness of the treated surface met the requirements for this parameter; during grinding, not a single plate was peeled off, which indicated that the plates did not heat up to the temperature of adhesive degradation.

At the same time, oxide ceramics were treated with grinding wheels, the mass composition of which corresponded to the mass composition of the prototype. About 4,500 pieces were processed with these circles until complete wear. plates. Due to the large heating of the plates during grinding, their separation from the support was observed.

Claims (1)

A mass for the manufacture of diamond tools, containing diamond, abrasive filler and a polymeric binder, characterized in that it contains boron carbide or electrocorundum as an abrasive filler and further comprises silicon carbide and a solid antifriction filler selected from the group consisting of molybdenum disulfide, hexagonal boron nitride , graphite, in the following ratio of components, vol.%:
diamond 12.5-37.5 abrasive filler 1,0-20,0 silicon carbide 5.0-40.0 solid anti-friction filler 0.5-5.0 polymer binder rest