RU2355922C2 - Metallic additive compound - Google Patents

Abstract

FIELD: engineering industry.

SUBSTANCE: invention refers to engineering industry, and is meant for being used as grease for friction assemblies, and namely in automobile production, in equipment intended for food industry, as well as in ship-repair and railway equipment. Metallic additive compound for modifying and restoring metal friction surfaces is prepared in the form of fine powder at the following component ratio, wt %: Mg₆(OH)₈Si₄O₁₀ - 92-96; SiC - 1-2; TiO₂ - 1-2; CuO - 2-4, and, in addition, fine powder Cu in quantity of 0.1 to 4% wt is added to the compound. Fine powder Mo in quantity of 0.1 to 3% wt can also be added to the compound. Maximum particle size of powder is 15 mcm.

EFFECT: decreasing friction forces and reducing wear rate of metal friction surfaces for a long period of time owing to increase of strength and life time of servovit film.

3 cl

Description

The invention relates to mechanical engineering and is intended for use, in particular, in the automotive industry, in equipment for the food industry, as well as in ship repair and railway equipment as a lubricant in friction units.

Compared to additives and other types of lubricants, solid lubricant compositions provide a greater degree of reduction in the coefficient of friction and, consequently, the wear of rubbing surfaces.

A number of compositions are known containing a filler and a carrier (binder), in which natural magnesium hydrosilicates are used as a filler.

[RF patent No. 2043393, IPC С10М 125/04, SOLID GREASING COATING / Marynich T.L. and etc.; Stated September 25, 1991; Published on September 10, 1995];

[RF patent No. 2088639, IPC С10М 177/00, METHOD FOR PRODUCING AN ADDITIVE TO LUBRICANTS / Yakovlev G.M .; Stated 06/10/1993; Published on August 27, 1997];

[RF patent No. 2059121, IPC F16C 33/14, METHOD FOR FORMING A SERVITAL FILM ON A FRACTING SURFACE / Yakovlev G.M .; Stated March 30, 1993; Published on April 27, 1996].

In all of the above analogues, the presence of powder in the lubricating composition under certain conditions of its use between the rubbing surfaces and their running-in leads to the formation of a servo film on the rubbing metal surfaces, significantly reducing their wear.

Strength and antifriction characteristics of a servovitic film depend on many factors: on its composition, preparation conditions of the composition and running-in of friction surfaces after the introduction of the composition, on the initial state of the mating surfaces.

Closest to the proposed invention is a lubricating composition and a method for its preparation [RF Patent No. 2035636, IPC F16C 33/14, METHOD FOR FORMING A SERVITAL FILM WITH A TRIBOTECH COMPOSITION / Khrenov A.Yu .; Declared 07.07.1993; Published on May 20, 1995].

The lubricating composition used to convert and restore metal friction surfaces according to this invention is a mixture of finely divided abrasive-like powder with a binder (carrier). As an abrasive-like powder, a composition containing:

- serpentine (Mg _6-x Al _x ) (Si _4-x Al _x ) O ₁₀ (OH) ₈ , at x = 0.75, 51-60 wt.%;

- talc Mg ₃ Si ₄ O ₁₀ (OH) ₂ , 20-40 wt.%;

- sulfur S, FeS pyotype, enstantite MgSiO ₃ , fayalite (Fe _0.94 Mg _0.06 ) SiO, 8-10 wt.% (taken in equal proportions).

However, the strength and durability of the servovitic film formed by this composition are insufficient and, therefore, the wear of rubbing metal surfaces in mechanisms operating in real conditions is high.

The technical result of this invention is to reduce the effects of friction and to reduce the wear rate of rubbing metal surfaces for a long period of time by increasing the strength and durability of the servo film.

The specified technical result is achieved in that the composition of the metal-containing additive for the conversion and recovery of rubbing metal surfaces is prepared in the form of a fine powder having a composition, wt.%:

Mg ₆ (OH) ₈ Si ₄ O ₁₀ 92-96 SiC 1-2 TiO ₂ 1-2 CuO 2-4

According to the invention, finely divided Cu powder is added to the composition in an amount of from 0.1 to 4 wt.%.

Also, finely dispersed Mo powder in an amount of from 0.1 to 3 wt.% Can be added to the composition. And the maximum particle size of the powder is 15 microns.

When this composition is introduced into the friction unit, abrasion occurs, which leads to the removal of the layer of oxides and surface compounds from the surfaces of the rubbing parts due to the high hardness of silicon carbide (7-8 units on the Mohs scale). In this case, Cu and CuO ions are introduced into the textured layer and the zone of plastic deformations, which leads to an increase in microhardness and fatigue strength of the subsurface layer. With abrasion, the temperature rises at which a chemical reaction occurs on the surface in microcontacts, resulting in the formation of polycrystalline forstenite in a siliceous phase.

To form crystallization centers and regulated grain growth, TiO ₂ is introduced into the composition of the lubricant composition, and in order to reduce the diffusion rate of atomic hydrogen (an oil degradation product), the matrix is modified by Mo, which is contained in the composition in an amount from 0.1 to 3 wt%.

As a result of the above physicochemical processes, a solid and durable servo film is formed on the surfaces.

The indicated ratios of the components provide maximum strength and wear resistance of the servo film for a long time.

Claims (3)

1. The composition of the metal-containing additives for the conversion and restoration of rubbing metal surfaces, prepared in the form of a fine powder having a composition, wt.%:
Mg ₆ (OH) ₈ Si ₄ O ₁₀ 92-96 SiC 1-2 TiO ₂ 1-2 CuO 2-4
characterized in that finely divided Cu powder is added to the composition in an amount of from 0.1 to 4 wt.%. 2. The metal-containing additive composition according to claim 1, characterized in that finely dispersed Mo powder is added to the composition in an amount of from 0.1 to 3 wt.%. 3. The composition of the metal-containing additive according to claim 1 or 2, characterized in that the maximum particle size of the powder is 15 microns.