Abstract: Powder which has primary particle size of not larger than 10 .mu.m and is formed of mixture of Ni powder and Cr powder added with hard particles containing carbide is mixed with Cr.sub.3 C.sub.2 powder and granulated and sintered, whereby flame spraying powder having secondary particle size of 5 to 53 .mu.m is formed. The flame spraying powder thus formed is flame-sprayed under conditions which will cause fused Ni.Cr to cover Cr.sub.3 C.sub.2 particles which are not fused, thereby binding the Cr.sub.3 C.sub.2 particles and causes the thickness of one Ni.Cr layer to be smaller than 5 .mu.m. In this manner, flame spray coating the porosity of which is not larger than 2% and the hardness of which is not lower than 700 (Hv: 200 g) can be obtained.

Abstract: A method for manufacturing a side housing of a rotary piston engine including the steps of forming a flame sprayed layer on the rotor sliding portion of the inner surface thereof and forming an anodized layer on a portion of the inner surface with the exception of the rotor sliding portion so as to eliminate a jamming of whetstone employed for an abrading process.

Abstract: A composite member is made by fitting a functional member constituted by an aluminum composite material capable of providing a desired target function to a recess of a base material constituted by an aluminum alloy and provided with the recess on the surface required to exhibit the desired target function. The entire peripheral section exposed at the outer surface among the joining sections of the base material with the functional member is beam-welded in a non-oxidizing atmosphere. The beam-welded base material and the functional member are then subjected to diffusion bonding by pressing them at least in the fitting direction and heating them.

Abstract: A method for manufacturing an apex seal for rotary piston engines, comprising steps of providing a substrate made of an iron based material and having a portion wherein a sliding surface is provided, spraying the portion of the substrate with a molten-state Co-Mo-Si type intermetallic compound to form a coating of the compound, heating the coating of the compound by applying electron beams or laser beams to thereby make the intermetal compound dispersed in the substrate, heating the substrate to 580.degree. to 780.degree. C. to anneal it and machining the substrate into a configuration of the apex seal. The apex seal made in accordance with this method is also disclosed.

Abstract: A sliding member having a number of oil retaining pores is manufactured by forming a hard plating layer on a metal base, forming a masking resist film on the hard plating layer by exposure to light and development, forming a number of pores in the hard plating layer by effecting electrolytic etching at a current density of 50 to 600 A/dm.sup.2, dissolving said masking resist film and removing the same, and forming a hard ceramic film on the hard plating layer by vapor phase plating.

Abstract: An apex seal for rotary piston engines comprising a material containing in weight 2.5 to 4.0% of C, 1.5 to 3.0% of Si, less than 1.0% of Mn, 0.25 to 2.0% of Ni, 0.25 to 2.0% of Mo, 0.25 to 2.0% of Cu, 0.05 to 0.3% of B, 0.2 to 1.5% of Cr, 0.05 to 1.0% of V and balance substantially of Fe. The sliding surface portion of the seal is of a chilled structure containing in area ratio more than 55% of carbides and the body portion is essentially of bainite structure containing in area ratio less than 15% of carbides.

Abstract: A valve-seat material ideal for valve seats for vehicle-engine exhaust valves with no cobalt contained therein, superior in general use, has superior wear-resistance in high-temperature oxidizing atmosphere, and can be used independently of types of fuel to be used in the non-lead gasoline, lead-contained gasoline, L.P.G. or the like. The recession amount of the valve is extremely decreased and the wear resistance is remarkably improved.