RU2451702C1 - Polymer composite antifriction material - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to production of polymer antifriction composite material for bearings and sliding supports for different purposes. The polymer composition is obtained by mechanically mixing components. The composition contains resol-type phenol-formaldehyde resin as binder, a mixture of polyoxadiazole fibre and cotton fibre as fibrous filler, an adhesive in form of polyvinyl acetate, an antiadhesive in form of zinc stearate and powdered filler - cast iron powder with particle size from 300 to 50000 nm.

EFFECT: composite material has simple composition, shorter process cycle for making articles from the material and low friction coefficient of the material.

2 tbl, 8 ex

Description

The invention relates to the creation of a polymer antifriction composite material for bearings and sliding bearings for various purposes.

Known metal-polymer compositions - plastics with a metal filler (iron, aluminum, and others), which use thermoplastics as a binder, as well as phenol-formaldehyde resin and other thermosets [1].

Known antifriction composite material [2], containing as a filler a mixture of polyoxadiazole fiber and cotton fiber, as a filler, graphite, silicon oxide, alumina, wollastonite, molybdenum disulfide, tungsten disulfide or antimony sulfide, as a thermosetting binder is phenol formaldehyde or cresol-formaldehyde resin in the form of novolac and / or rezol form, as an adhesive - polyvinyl acetate and / or polyvinyl butyral and as a release agent - zinc stearate and / or calcium stearate in the following quantitative content of the components.

Known antifriction composite material provides a decrease in the intensity of linear wear of both the support material and the material of the counterbody made of metal, and has an increased microhardness. The disadvantages of the known material include the complex composition and operating temperature of not higher than 140 ° C. In addition, the increased microhardness of the matrix, while reducing wear, does not allow achieving the required values of the coefficient of friction.

Known antifriction composite material [3], containing a binder of phenol-formaldehyde resin and an organic solvent and a woven filler, consisting of an outer layer made of polytetrafluoroethylene yarns interwoven with an inner layer made of high-strength high-modulus polyimide fibers.

Known anti-friction composite material is operable at high specific loads, has a reduced coefficient of friction and increased strength when peeling from metal. The disadvantages are the operating temperature is limited to 150 ° C, insufficient strength at elevated sliding speeds and loads.

The closest in technical essence and the set of essential features to the claimed technical solution is an antifriction composite material containing, as a binder, a phenol-formaldehyde resin in the form of novolac and / or resol form, or a cresol-formaldehyde resin, as a fibrous filler, a mixture of polyoxadiazole fiber and cotton fiber, polyvinyl acetate and / or polyvinyl butyral as an adhesive, and further comprises zinc stearate and / or with calcium earat as particulate filler comprises graphite, aluminum oxide, silicon oxide, molybdenum disulfide, tungsten disulfide, antimony sulfide or [4].

However, the known antifriction composite material in its use has the following disadvantages: the composition is quite complex; antisynergetic effect is possible (Synergetic effect is the interaction of two or more factors (components), characterized by the fact that their action significantly exceeds the effect of each individual component in the form of their simple sum [5]) effect due to the mutual influence of a large number of heterogeneous components.

The invention solves the problem of expanding the range of polymer antifriction compositions obtained by molding them into blanks while reducing the manufacturing cycle.

The technical result of the claimed invention is to simplify the composition, reduce the technological cycle of manufacturing products, reduce the coefficient of friction of the material.

The technical result is achieved by the fact that the polymer composition for the manufacture of preforms obtained by mechanical mixing of the components, where the phenol-formaldehyde resin is used only as a resole type, as a filler a mixture of polyoxadiazole fiber and cotton fiber, an adhesive in the form of polyvinyl acetate, an anti-adhesive in the form of stearate zinc and powder filler - cast iron powder with particle sizes from 300 to 50,000 nm with the following components, wt.%:

fiberfill 38-70 powder filler 3.0-18.0 release agent 0.1-0.9 adhesive 2.4-11.6 binder rest.

The novelty is that phenol-formaldehyde resin of the rezol type is used as a binder, the powder filler is cast iron powder with particle sizes from 300 to 50,000 nm, and the content of the powder filler is 3.0-18.0 wt.%.

The inventive material is made by mechanical mixing of an aqueous or alcoholic solution of phenol-formaldehyde resin, a fibrous filler, a powder filler - cast iron, adhesive and anti-adhesive. Then the material is dried and granulated. To obtain blanks, the material is molded into products at a temperature of 120-150 ° C by direct pressing.

The limits of the resin content are established on the basis of the generally accepted position that, to ensure the necessary fluidity of the composition during pressing or injection molding while minimizing shrinkage, the volumetric content of the solid phase should be in the range 65–45%.

Table 1 The content of the components (mass parts) No. Binder - base, phenol-formaldehyde resin Fiberfill Powder filler, cast iron powder Release agent, zinc stearate Adhesive, Polyvinyl Acetate one 25 38 0.7 (300 nm) 0.1 11.6 2 47 70 5.0 (300 nm) 0.9 11.6 3 47 70 5.0 (300 nm) 0.1 11.6 four 25 38 5.0 (500 nm) 0.9 2,4 5 25 38 5.0 (1000 nm) 0.9 2,4 6 47 70 0.7 (300 nm) 0.9 2,4 7 47 70 0.7 (300 nm) 0.1 11.6 8 47 70 0.7 (300 nm) 0.9 11.6

table 2 Established Characteristics of the Anti-Friction Composite Material No. Coefficient of friction The total wear of the friction pair, μm / km The limit of compressive strength, MPa Impact strength, kJ / m ² Delamination resistance one 0.13 1,2 * 10 ^-7 168 25 No stratification 2 0.12 7 * 10 ^-8 182 35 No stratification 3 0.13 9 * 10 ^-8 180 32 No stratification four 0.11 8 * 10 ^-8 180 29th No stratification 5 0.10 8 * 10 ^-8 179 28 No stratification 6 0.10 8 * ^10-8 155 28 No stratification 7 0.11 8 * 10 ^-8 159 28 No stratification 8 0.09 8 * 10 ^-8 153 27 No stratification

As follows from the data of tables 1 and 2, a change in the content of these components leads to the fact that the coefficient of friction is reduced by 10-20%.

Thus, patentable boundaries for the content of components should be considered reasonable.

BIBLIOGRAPHY

1. Natanson E.M., Bryk M.T. Metal-polymer materials and products, M., 1979.

2. Patent RU No. 2302564, IPC F16C 33/12, published 02/10/2006.

3. Patent RU No. 2313010, IPC C08L 63/00, published December 20, 2007.

4. RF patent No. 2278878, IPC С08L 61/10, 2005

5. Physics: Encyclopedia. / Under. Ed. Yu.V. Prokhorova. - M .: Big Russian Encyclopedia, 2003 .-- 944 p.

Claims (1)

An antifriction composite material containing a resol-type phenol-formaldehyde resin, a fiber filler — a mixture of polyoxadiazole fiber and cotton fiber, an adhesive in the form of polyvinyl acetate, an anti-adhesive in the form of zinc stearate and a powder filler, characterized in that cast iron with powder is used particle sizes from 300 to 50,000 nm with the following content of components, wt.%:
fiberfill 38-70 powder filler 3.0-18.0 release agent 0.1-0.9 adhesive 2.4-11.6 binder rest