process for the production of keramikartigen lagerbauteilen with eigenschmierwirkung

摘要

1,230,921. Bearing material; piston rings. DOW CORNING CORP. 25 April, 1969 [27 May, 1968], No. 21177/69. Headings F2A and F2T. Self-lubricating bearings and piston rings are made by shaping a mixture of the composition given below, and heating the shaped mixture to a temperature above 500‹ C. until a ceramic article is obtained. The mixture comprises (1) 3 to 50% by weight of an organopolysiloxane resin having 1 to 3 substituents per silicon atom selected from hydrogen and organic radicals attached to the silicon through Si-C linkages, the organic radicals being composed of carbon, hydrogen and if desired nitrogen and oxygen atoms, there being no more than 18 hydrogen atoms per organic radical; (2) 0 to 30% by weight of a particulate or fibrous filler selected from silica, alumina aluminium, copper, bronze, talc, silicon carbide, tungsten carbide, zirconium silicate, mica, potassium carbonate, sodium carbonate, boron oxide, asbestos, magnesium silicate, aluminium silicate, calcium silicate, lithium aluminium silicate, magnesium oxide, thorium oxide; and (3) 50 to 97% by weight of a finely divided self-lubricating material having an average particle size of 4 to 10 microns. The self-lubricating material is made up of at least 50% by wt. of a material chosen from graphite, boron nitride, and sulphides, selenides and tellurides of molybdenum tungsten, titanium, zirconium, hafnium, niobium, and thorium; any remaining material being selected from calcium fluoride, zinc oxide, potassium titanate, zinc sulphide, and antimony trioxide.