A highly wear-resistant valve seat insert for an internal combustion engine, having a material composition in which hard-particles are uniformly and finely dispersed in the matrix phase, and which is excellent in wear-resistance and radial crushing strength, based on a blended fine powder and a matrix forming powder with a particle size approximately equal to that of the hard-particles so as to prevent the hard-particles from aggregating and thus coarsely dispersing as a hard-particle phase.

A piston for an internal combustion engine and method of construction thereof are provided. The piston includes an upper crown formed at least in part by a first metal material and a thermally insulating insert. The upper crown has an upper wall forming an upper combustion surface and a ring belt region. The upper combustion surface is formed at least in part by the thermally insulating insert. The thermally insulating insert has a base surface with pores extending upwardly therein. The first metal material is infused and solidified in the pores, with the first metal material forming a first bonding surface. The piston further includes a body portion formed from a second metal material. The body portion provides pin bosses having coaxially aligned pin bores and diametrically opposite skirt portions. The body portion has a second bonding surface bonded to the first bonding surface of the first metal material.

Inside a sealed container (101) of a refrigerant compressor (100), lubricating oil (103) having a kinematic viscosity at 40 C. of 0.1 mm.sup.2/S to 5.1 mm.sup.2/S is stored, and an electric element (106) and a compression element (107) are accommodated. The compression element (107) is provided with, as a shaft part, a crankshaft (108) comprising a main shaft (109) and an eccentric shaft (110), and as bearing parts, a main bearing (114) that axially supports the main shaft (109) and an eccentric bearing (119) that axially supports the eccentric shaft (110). At least one surface of the main shaft (109) and the eccentric shaft (110) is subjected to a surface treatment, e.g., formation of an oxide film, having a hardness equal to or greater than that of a bearing part (the main bearing (114) or the eccentric bearing (119)). Satisfactory reliability in sliding parts can thereby be achieved even if lubricating oil having lower viscosity is used.

A swash plate 3 includes a substrate 11 made of an iron-based material, a hard first resin layer 12 provided to coat an end surface of the substrate 11, and a soft second resin layer 13 provided to coat the first resin layer 12. A spiral annular groove 12A is formed in a surface of the first resin layer 12, and the second resin layer 13 is provided to match the sectional shape of the first resin layer 12. With the soft second resin layer 13 on a sliding surface 3A of the swash plate 3, a swash plate 3 having a good fit in an initial stage of sliding can be provided. When the second resin layer 13 partially wears, a protrusion 12 of the first resin layer 12 of the hard resin is exposed to provide good wear resistance and good sliding properties.

A cam ring and plate module for vehicle vacuum pumps in which, when an oxide layer formed through steam treatment comes into contact with a carbon or graphite material, a uniform carbon layer is stacked on the oxide layer so as to improve corrosion resistance, wear resistance, hardness and seal resistance.

A cam ring and plate module for vehicle vacuum pumps in which, when an oxide layer formed through steam treatment comes into contact with a carbon or graphite material, a uniform carbon layer is stacked on the oxide layer so as to improve corrosion resistance, wear resistance, hardness and seal resistance.

A cam ring and plate module for vehicle vacuum pumps in which, when an oxide layer formed through steam treatment comes into contact with a carbon or graphite material, a uniform carbon layer is stacked on the oxide layer so as to improve corrosion resistance, wear resistance, hardness and seal resistance.