The invention relates to an imide polymer-based solid film lubricant, a method for producing same, a sliding element comprising same and the use thereof. According to the method, difunctional or cyclized difunctional compounds and optionally functional fillers are added to a non-imidized or partly imidized polyamide acid prepolymer or an imidized short-chain blocked prepolymer in a solvent or solvent mixture and then, depending on the prepolymer, a polymerization reaction or an imidization reaction and in both cases a crosslinking reaction is carried out. The solid film lubricant comprises an imide polymer as the resin matrix and optionally functional fillers, the molecules of the imide polymer comprising groups (R.sub.1) of the difunctional compounds that additionally contribute to the crosslinking.

An abradable coating is formed on a mechanical part from a polymer resin-containing powder deposited over a polymer resin-containing liquid that is substantially free of volatile organic hydrocarbons. The liquid and the powder are then cured together to form an abradable coating. The polymer resin-containing powder may include a first thermosetting resin and a filler having a melting point above a cure temperature of the first thermosetting resin. The interactions of the powder and the liquid result in a durable abradable coating. Because the liquid is substantially free of volatile organic hydrocarbons, overspray may be recovered and used to coat other parts.

An engine component, for example a piston ring, including a wear resistant coating applied by physical vapor deposition (PVD) is provided. The coating includes tetrahedral amorphous carbon (ta-C), the carbon of the coating includes sp.sup.3 hybrid orbitals, and the coating includes boron in an amount of 0.1 wt. % to 4.0 wt. %, based on the total weight of the coating. The doped boron makes the coating less sensitive to the ion energy during the physical vapor deposition (PVD) process, improves adhesion of the coating, and expected to reduce compressive stress in the coating. Thus, the boron-doped ta-C coating can be applied to a greater thickness compared to ta-C coatings without the doped boron. In addition, there is a strong indication that the addition of boron will maintain a high level of sp.sup.3 bonded carbon and a high microhardness.

A piston may be provided which includes a first piston body portion having an end wall extending radially about a central axis along which the piston reciprocates. The piston may also include a second piston body portion having an end wall extending radially about a central axis along which the piston reciprocates. The first piston body portion and the second piston body portion are axially opposed. The piston may further include a first piston rod bore disposed in the first piston body portion extending along the central axis and a second piston rod bore disposed in the second piston body portion extending along the central axis. The piston may also include a circumferential opening disposed between the mating of the first piston body portion with the second piston body portion.

A piston may be provided which includes a first piston body portion having an end wall extending radially about a central axis along which the piston reciprocates. The piston may also include a second piston body portion having an end wall extending radially about a central axis along which the piston reciprocates. The first piston body portion and the second piston body portion are axially opposed. The piston may further include a first piston rod bore disposed in the first piston body portion extending along the central axis and a second piston rod bore disposed in the second piston body portion extending along the central axis. The piston may also include a circumferential opening disposed between the mating of the first piston body portion with the second piston body portion.

Piston (1) of an internal combustion engine, which piston is designed in structured construction, comprising two oppositely arranged load-bearing skirt wall portions (2), wherein a connecting wall (3) respectively extends, starting from a pin boss (4), in the direction of the side edge of the load-bearing skirt wall portions (2), characterized in that in an interior of the piston (1) is (are) disposed at least one rib (5, 6, 7), preferably three ribs (5, 6, 7), and the material of the regions around the at least one rib (5, 6, 7) is reduced.

Piston (1) of an internal combustion engine, which piston is designed in structured construction, comprising two oppositely arranged load-bearing skirt wall portions (2), wherein a connecting wall (3) respectively extends, starting from a pin boss (4), in the direction of the side edge of the load-bearing skirt wall portions (2), characterized in that in an interior of the piston (1) is (are) disposed at least one rib (5, 6, 7), preferably three ribs (5, 6, 7), and the material of the regions around the at least one rib (5, 6, 7) is reduced.

A piston for a compressor includes a bearing portion having a cylindrical shape to define a suction space into which refrigerant is accommodated therein, the bearing portion being provided with a bearing surface facing an inner circumferential surface of the cylinder, a head portion coupled to a front opening of the bearing portion and provided with a plurality of suction ports which communicate with the suction space, the head portion having a compression surface configured to face a compression space to compress the refrigerant in the compression space, and a flange portion coupled to a rear opening of the bearing portion and provided with a through-passage through which the refrigerant is introduced from a muffler unit to the suction space, the flange portion being coupled to a driving portion to transmit driving force to the piston. The bearing surface is subjected to a surface treatment to improve abrasion resistance.

A piston for a compressor includes a bearing portion having a cylindrical shape to define a suction space into which refrigerant is accommodated therein, the bearing portion being provided with a bearing surface facing an inner circumferential surface of the cylinder, a head portion coupled to a front opening of the bearing portion and provided with a plurality of suction ports which communicate with the suction space, the head portion having a compression surface configured to face a compression space to compress the refrigerant in the compression space, and a flange portion coupled to a rear opening of the bearing portion and provided with a through-passage through which the refrigerant is introduced from a muffler unit to the suction space, the flange portion being coupled to a driving portion to transmit driving force to the piston. The bearing surface is subjected to a surface treatment to improve abrasion resistance.

The present disclosure provides a piston for an internal combustion engine, the piston having a piston body including a first bearing saddle defining a first axis and a second bearing saddle defining a second axis, the first axis being parallel to and spaced from the second axis. A bearing is also provided, the bearing having a first journal having a first body, longitudinal ends, and lateral edges, the first journal defining a first axis, the first journal disposed about approximately 180 degrees of the first axis and a second journal having a second body and defining a second axis, the second journal disposed about approximately 180 degrees of the second axis, the second journal operable to be positioned abutting one of the lateral edges of the first journal when the first and second journals are positioned with the piston.