GB848898A - Plain bearings and materials for making such bearings - Google Patents

Abstract

<PICT:0848898/IV(a)/1> A plain bearing comprises a substantially homogeneous mixture of discrete metallic fibres B and non-metallic material such as plastic, the metallic fibres constituting a series of closely spaced substantially continuous metallic heat-conducting paths each extending from the bearing surface B2 to the metallic bearing housing A. Preferably the length of at least a substantial proportion of the fibres is not less than the thickness of the bearing and the diameter approximately 0,001 inches. The non-metallic material may be nylon, polytetrafluoroethylene or a mixture of finely divided carbon and pitch, and it may include graphite or molybdenum disulphide, kieselghur or glass fibre. The metallic fibres may consist partly or wholly of iron and/or bronze and/or stainless steel. The bearing surface may consist of a very thin layer of pure P.T.F.E. or pure nylon. In one method of making a bearing, iron filaments were stirred into an aqueous suspension of P.T.F.E. and a coagulant of aluminium chloride added. After removal of the supernatant water and further mixing, the mixture was dried and formed into bearings by moulding and subsequent sintering. In another method, a mixture of cadmium plated copper wire fibres and fine P.T.F.E. powder were mixed in a high speed rotary mixing machine and then compression moulded. The bearing was subsequently slowly heated to 380 DEG C. and then slowly cooled.