GB1284835A - Composite bearing materials - Google Patents

Abstract

1284835 Bearing material KARL SCHMIDT GmbH 16 Nov 1970 [24 Dec 1969] 54480/70 Heading B2E [Also in Division F2] A bearing material comprises a metallic backing and a sliding layer made of a polyamide-type plastics material consisting of a polymer which has been produced by the condensation polymerisation of a diester of an unsaturated aliphatic dicarboxylic acid with an aliphatic and/or aromatic diamine in the presence N-methyl pyrrolidone and optionally a cross-linking agent, said condensation polymer incorporating at least 5% by weight of polymerized N-methyl pyrrolidone. The sliding layer may have a thickness of up to 200 microns and may contain between 0.02 and 0.2% by volume of oil and one or more lubricating fillers, e.g. lead, white metal, bronze, aluminium alloy, silver, silver alloy, zinc alloy, graphite of a particle size below 33 microns or a plastics material in amounts of up to 50% by volume. The metallic backing may be roughened, embossed with a waffle pattern or provided with a porous layer of sintered bronze before the sliding layer is applied. The condensation polymer may be applied in an intermediate stage of polymerisation, suitably with one or more lubricating fillers mixed with it, and the polymer may then be baked in a first stage of a temperature about 150‹C. for 15 to 60 minutes and then in a second stage at a temperature of 200‹C. for 20 to 60 minutes. Preferably the condensation polymer is applied in a plurality of layers, each layer being applied before the previously applied layer has been completely cured and the structure is completely cured only in a final baking operation. The sliding layer may be subjected to a vacuum treatment in. oil in order to introduce oil into the layer.