Abstract: This invention provides a self-lubricating composite material which has excellent strength and oxidation resistnce at a high temperature and can be used in air and in vacuum, and a production method thereof, the composite material is a Cu--Ni--Sn type composite sintered body containing 20 to 70 vol % of mixed particles of graphite and WS.sub.2 as the solid lubricant components and having a porosity of not greater than 25 vol %, and a matrix is a two-phase alloy comprising Cu--Ni alloy particles and an Sn single phase or an Sn--Ni intermetallic compound dispersed uniformly in the grain boundary of the alloy particles and firmly bonding them, and this matrix encompasses the solid lubricant particles. The matrix consists of 5 to 40 wt % of Ni, 4 to 15 wt % of Sn and the balance of Cu and unavoidable impurities as the alloy composition.

Abstract: The present invention is characterized by ceramic materials comprising ceramic sintered bodies consisting of (1) 1-90 wt % chromium carbide and the remainder carbonic titanium nitride; (2) 1-90 wt % chromium carbide, 0.1-5 wt % B.sub.4 C and the remainder titanium carbo-nitride; or (3) either of the above compositions plus less than 95 wt % of a metal boride such as Ti or Zr. Such ceramic sintered bodies are used for cutting tools or wear-resistant machine parts because of their high density, high hardness and high strength.

Abstract: A refractory ceramic body having excellent bending strength and high hardness and with little porosity is obtained by sintering a powdery mixture comprising 5 to 95% by weight of a titanium carbonitride and 95 to 5% by weight of a metal boride such as metal diborides, e.g. titanium diboride, W.sub.2 B.sub.5 and Mo.sub.2 B.sub.5 at a temperature of 1700.degree. to 1800.degree. C. Further improvements can be obtained by partial replacement of the above mentioned components with elementary boron, titanium carbide or titanium nitride or when the titanium carbonitride component is a combination of at least two kinds of titanium carbonitrides having different chemical compositions relative to the proportion of the carbon and nitrogen.

Abstract: Self-lubricating wear-resistant composite materials are produced by blending a metal powder matrix with a combination of molybdenum disulfide and tungsten disulfide powders, compression-molding the blend and then sintering the molding at 800.degree. to 1000.degree.C. When the combination of molybdenum disulfide and tungsten disulfide is blended with a metal powder matrix as described above, the molybdenum disulfide reacts with the metal powder matrix and consequently reinforces the metal matrix and the tungsten disulfide is dispersed as a lubricant element in the resultant composite material, giving rise to a composite material excellent in mechanical strength and lubricating property.