RU2412276C1 - Composition of anti-friction coating - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: invention refers to antifriction coating for protection of heavy loaded friction pairs of nominally stationary vibratory loaded joints of metal-metal, metal-polymer composition material from wear in interval of temperatures (-60)-(+250)°C. Composition of anti-friction coating has the following composition, wt %: molybdenum disulphide 35-45, colloid graphite 8-15, quazi-crystal of system Al-Cu-Fe polished with boron 5-10, epoxy varnish - the rest.

EFFECT: raised wear resistance at low friction coefficient in wide temperature range.

3 tbl, 3 ex

Description

The invention relates to the field of mechanical engineering and, in particular, to antifriction coatings for the protection of heavily loaded friction pairs of nominally stationary vibro-loaded joints metal-metal, metal-polymer composite material from wear in the temperature range (-60) - (+ 250) ° C.

It is known a fretting-resistant coating of the following composition, wt.%: Epoxy high molecular weight Diane resin 2.0-16; epoxy low molecular weight diane resin 0.05-1.0; phenol formaldehyde resole resin 1.0-8.0; alkyd glyphthalic resin 0.05-1.0; molybdenum disulfide 6.0-20.0; colloidal graphite preparation 0.9-14.0; phosphoric acid 0.01-0.3; 1.7-bisoxymethylcarborane 1.5-2.6; 2-ethoxyethanol - the rest (RF patent No. 1711200).

The disadvantage of this coating is the multicomponent composition of the binder, including a toxic substance - formaldehyde.

Known sintered antifriction material based on cobalt, containing, wt.%: Titanium carbide 5.0-7.0; molybdenum disulfide 13.0-15.0; Manganese 2.0-2.5; cerium 0.1-0.15; cobalt - the rest (RF patent No. 2360991).

The disadvantage of this material is the high coefficient of friction of the material and the use of cobalt, which is a fairly toxic element, as the main component.

The closest in purpose and technical essence adopted for the prototype is an anti-friction solid lubricant coating containing, wt.%: Molybdenum disulfide 50-70; colloidal graphite 7-20; β-modification silicon carbide whiskers with a ratio of length to diameter of 30-300 0.15-1.1 and epoxyphenol varnish - the rest (RF patent No. 20177800).

The coating is designed to protect heavily loaded metal-metal friction pairs from wear in the temperature range (-60) - (+ 250) ° C.

The disadvantage of this coating is its low manufacturability, expressed in its tendency to form lumps from silicon carbide whiskers as felt and a rather low wear resistance in the temperature range (-60) - (+ 250) ° C.

The objective of the invention is to increase the wear resistance of the coating with a low coefficient of friction in the temperature range (-60) - (+ 250) ° C.

To achieve this objective, an anti-friction coating composition is proposed containing molybdenum disulfide, colloidal graphite, an epoxy-based binder, characterized in that the coating additionally contains an Al-Cu-Fe quasicrystal doped with boron, and an epoxy varnish as a binder in the following ratio of components , wt.% .:

molybdenum disulfide 35-45 colloidal graphite 8-15 quasicrystal system Al-Cu-Fe doped with boron 5-10 epoxy varnish rest

The introduced quasicrystal of the Al-Cu-Fe system is a finely divided powder ~ 3 μm in size, doped with boron. The presence of a quasicrystal in the coating reduces carbon deposits, lowers the coefficient of friction, and the ductility of the quasicrystal allows filling cracks, cavities and scratches, which increases the wear resistance of the product.

Application as a binder epoxy varnish allows you to evenly apply the proposed coating on the surface of the product.

An example implementation.

The following components were used to prepare an antifriction coating with quasicrystals:

- molybdenum disulfide brand DM-1 TU 48-19-133-85;

- colloidal graphite of dry grade S-1 OST 6-08-431-75, obtained from thermographite or natural graphite, which is a highly dispersed low-ash dry graphite with a basic particle size of up to 4 microns, containing ash not more than 0.8%;

- a quasicrystal of the Al-Cu-Fe system doped with boron, grade VKK1B TU 1-595-31-1081-2009;

- epoxy varnish EP074 TU 6-10-1030-76.

To prepare the coating used the following technology. The calculated amount of molybdenum disulfide, colloidal graphite, and a quasicrystal doped with boron was introduced into the binder. The prepared mixture was mixed in a bead mill and applied to the protected surface with a spray gun, brush or dipping, and was dried at room temperature.

Table 1 shows the compositions for the antifriction coating made by the above technology, of which 1-3 are claimed, 4 is the prototype.

Table 2 presents the properties of antifriction coatings on 30KhGSA steel, including such characteristics as wear resistance and friction coefficient.

The coatings were tested on 30KhGSA steel, in conditions of face friction at R _beats - 15 MPa, V _rotation - 0.31 m / s, at a temperature of +250, +20, -60 ° C.

From table 2 it is seen that the coating based on the proposed compositions has the lowest wear rate.

Table 3 presents the results of the coating test in the design of a spherical spherical plain bearing made of 95X18 steel.

Antifriction coatings containing a quasicrystal are tested in the design of a spherical spherical plain bearing made of 95X18 steel. The coatings were applied to the inner surface of the bearing race according to the technology presented above and tested in the rocking motion mode with the following parameters:

- load 75 and 100 MPa; - temperature +20 and + 250 ° C; - swing frequency 0.04 Hz; - swing angle ± 10 °; - Wednesday air.

From table 3 it can be seen that the proposed anti-friction coating is operable in air in the temperature range from -60 to + 250 ° C, at specific loads up to 100 MPa. Thus, the use of the proposed antifriction coating provides protection of heavily loaded friction pairs from wear in the temperature range -60 to + 250 ° C.

Table 1 No. Structure Coating components, wt.% Β-modification silicon carbide whiskers Epoxy varnish Molybdenum disulfide Graphite Boron doped quasicrystal one proposed 40 40 fifteen 5 - 2 proposed 35 45 12 8 - 3 proposed 47 35 8 10 - four prototype 42.74 (varnish fifty 7 - 0.26 epoxyphenolic)

table 2 No. Wear rate, μm / h, at P _beats = 15 MPa, V = 0.31 m / s To _friction -60 ° C 20 ° C 250 ° C one 0.16 0.08 2.4 0.10 2 0.15 0.07 2.5 0.09 3 0.17 0.09 2.7 0.07 four 0.25 0.14 6.8 0.08

Table 3 Load, MPa Test temperature ° C Coefficient of friction Wear rate, μm / h Proposed: 75 twenty 0.13 0.18 75 250 0.14 2.9 one hundred twenty 0.12 0.2 one hundred 250 0.12 3.7 Prototype: 75 twenty 0.12 0.24 75 250 0.14 4.9 one hundred twenty 0.13 0.26 one hundred 250 0.16 6.3

Claims (1)

The composition of the antifriction coating, including molybdenum disulfide, colloidal graphite, an epoxy-based binder, characterized in that it additionally contains a quasicrystal of the Al-Cu-Fe system doped with boron, uses an epoxy varnish as a binder, in the following ratio, wt.%:
molybdenum disulfide 35-45 colloidal graphite 8-15 quasicrystal of the Al-Cu-Fe system, doped with boron 5-10 epoxy varnish rest