SU462472A1 - Method of producing friction material - Google Patents

Abstract

Process for the preparation of the friction material by molding smesina'osnove butadiene Cow "1uka, combined with butadiene or butanol dienmetilstirolnym Cau ^^ ukoma and phenol-formaldehyde resin, followed by heat treatment, and u * differing with the fact that, with improvement .target material quality, heat treatment is carried out sequentially at 100-170 ° C, 170-200 ° C, 200-250 ° C for 2-4 hours at each temperature.

Description

This invention relates to methods for producing friction materials used in clutches of automobiles and tractors.

A method of producing friction material is known by molding a mixture based on butadiene nitrile rubber combined with butadiene or butadiene methyl styrene rubber and phenol-formaldehyde resin, followed by heat treatment at 170-180 ° C. The disadvantage of this method is that the material obtained has insufficient mechanical strength at 170-180 ° C. which makes it unsuitable for use in the coupling points of automobiles and tractors of high energy load.

The aim of the invention is to improve the quality of the material. This goal is achieved by the fact that the heat treatment is carried out sequentially at 1.60170 ° C, 170-200 ° C, 200-250 ° C for 2-4 hours at each temperature.

The proposed method is a lean.

First, mixtures based on butadiene nitrile rubber and butadiene or butadiene methyl styrene rubber, including phenol formaldehyde resin, are made. The mixture includes a vulcanizing group, as well as asbestos, barite, graphite, alumina, zinc oxide, and metallic inclusions. Then, after drying and grinding, the mixture is subjected to molding, and the molded material is subjected to heat treatment in a stepwise mode; Temperature, ° С Time, h 100-1402

160-180 2

200-2502-4

The material obtained is characterized by high indicators of wear resistance, mechanical strength and heat resistance.

Example, Friction material is made of the following ingredients,%: phenol-formaldehyde resin 6.5; polymer product 13.0; sulfur 3Ш 1,8 1,8 kantax 0,13; thiuram 0.07; barite 5.6; graphite 7.5; zinc oxide 3.8; alumina 5.5; metal inclusions 11.8; coal coke 4.7; sodium oleate 16.0; asbestos 38.0. Polymer product is preliminarily prepared on rollers consisting of butadiene nitrile and butadiene methyl styrene rubbers in a 1: b ratio. The prepared polymer product is loaded into a mixer with Z-shaped blades, gasoline is poured in there, and then resin and all porous fillers except asbestos are charged. After careful development of the mixture, the vulcanizing group is charged to a uniform state, asbestos is poured, and gasoline is poured. The whole mixing time is 3.5-4 hours. After drying and grinding, the molding mass is molded first in molds without heating, and then in hot molds at 170-180 ° C and time 5- 8 min The molded products are subjected to additional thermal treatment in the following stepwise mode: Temperature, С Time, h 100-1402 160-1802 200 2502-4 The friction material according to the proposed method was tested for mechanical strength on the ICAR stand “The test results are listed in the table” Known - 5300 4600 3100 2900 Offered 7300 6300 5000 4300 As can be seen from the table, the material according to the proposed method is maintained at both normal and elevated temperatures 1.4-1.6 times more X revolutions before destruction than the material obtained by the known spos boo,

Claims (1)

METHOD FOR PRODUCING FRICTIONAL MATERIAL by molding a mixture on the basis of nitrile butadiene rubber combined with butadiene or styrene butadiene rubber and phenol-formaldehyde resin, followed by heat treatment, which distinguishes heat treatment in order to improve the quality of the material C, 170-200 ° C, 200-250 ° C for 2-4 hours at each temperature.