An internal combustion engine includes an engine block, a piston, a cylinder head, and a valve train. The engine block includes a cylinder block including a cylinder bore and a crankcase defining a crankcase chamber with a crankshaft positioned within the crankcase chamber. The piston is coupled to the crankshaft and configured to reciprocate within the cylinder bore. The cylinder head is coupled to the cylinder block. The valve train includes a camshaft, a first and second pushrod, a first and second rocker arm, an exhaust valve housed, and an intake valve. The first rocker arm, the second rocker arm, the exhaust valve, and the intake valve each include at least a layer of a low friction material. The first and second pushrod each pass through a pushrod seal to prevent fluid from reaching the rocker chamber to fluidly isolate the rocker chamber from the crankcase chamber.

A sliding member includes a base substrate and a coating layer formed on the base substrate. The coating layer includes an inorganic part derived from at least one type of inorganic particles selected from the group consisting of iron base alloy particles, cobalt base alloy particles, chromium base alloy particles, nickel base alloy particles, molybdenum base alloy particles, and ceramic particles, and a metal part derived from at least one type of metal particles selected from the group consisting of iron base alloy particles other than listed in the above group, copper particles, and copper alloy particles. The inorganic part is bonded to another inorganic part and/or the metal part via interfaces therebetween, and the metal part is bonded to another metal part and/or the inorganic part via interfaces therebetween. The sliding member includes an interface layer including at least one of a diffusion layer and an intermetallic compound layer on at least one part of an interface between the base substrate and the coating layer or interfaces between the inorganic part and the metal part, the inorganic parts, and the metal parts. The interface layer has a thickness of equal to or less than 2 μm.

A sliding member includes a base substrate and a coating layer formed on the base substrate. The coating layer includes an inorganic part derived from at least one type of inorganic particles selected from the group consisting of iron base alloy particles, cobalt base alloy particles, chromium base alloy particles, nickel base alloy particles, molybdenum base alloy particles, and ceramic particles, and a metal part derived from at least one type of metal particles selected from the group consisting of iron base alloy particles other than listed in the above group, copper particles, and copper alloy particles. The inorganic part is bonded to another inorganic part and/or the metal part via interfaces therebetween, and the metal part is bonded to another metal part and/or the inorganic part via interfaces therebetween. The sliding member includes an interface layer including at least one of a diffusion layer and an intermetallic compound layer on at least one part of an interface between the base substrate and the coating layer or interfaces between the inorganic part and the metal part, the inorganic parts, and the metal parts. The interface layer has a thickness of equal to or less than 2 μm.

Provided is cladding alloy powder that can keep enough corrosion resistance of the cladding portion on the engine valve and can suppress adherence of the cladding portion to the valve seat. Cladding alloy powder is to form a cladding portion at an engine valve that comes in contact with a valve seat of an engine. The cladding alloy powder includes 22 to 27 mass % of Cr; 10 to 30 mass % of Mo; 2.0 to 6.0 mass % of W; 0.40 to 1.30 mass % of C; 3.0 mass % or less of Si; 15.0 mass % or less of Ni; 30.0 mass % or less of Fe; and 0.4 mass % or less of S as well as Co and unavoidable impurity as a remainder, and satisfies Cr(−0.53C+1.2)+Mo(−1.2C+2.8)≥24 and 23W+2.7Mo≥73.

Provided is cladding alloy powder that can keep enough corrosion resistance of the cladding portion on the engine valve and can suppress adherence of the cladding portion to the valve seat. Cladding alloy powder is to form a cladding portion at an engine valve that comes in contact with a valve seat of an engine. The cladding alloy powder includes 22 to 27 mass % of Cr; 10 to 30 mass % of Mo; 2.0 to 6.0 mass % of W; 0.40 to 1.30 mass % of C; 3.0 mass % or less of Si; 15.0 mass % or less of Ni; 30.0 mass % or less of Fe; and 0.4 mass % or less of S as well as Co and unavoidable impurity as a remainder, and satisfies Cr(−0.53C+1.2)+Mo(−1.2C+2.8)≥24 and 23W+2.7Mo≥73.

A gas exchange valve for an internal combustion engine may include a valve stem and a wear resistance improving functional layer. The valve stem may extend in an axial direction and may transition into a valve plate in the axial direction. The functional layer may include nickel and tungsten. The functional layer may be arranged in a coating area on an outer circumference of the valve stem and may at least partially define a sliding surface.

A gas exchange valve for an internal combustion engine may include a valve stem and a wear resistance improving functional layer. The valve stem may extend in an axial direction and may transition into a valve plate in the axial direction. The functional layer may include nickel and tungsten. The functional layer may be arranged in a coating area on an outer circumference of the valve stem and may at least partially define a sliding surface.

An apparatus for a combustion cylinder of a reciprocating piston engine includes a combustion cylinder end face component including a first side configured to face the combustion cylinder and extending in a radial direction of the combustion cylinder and a pocket recessed into the first side and including a recessed pocket surface. The combustion cylinder end face component may be one of a piston and a cylinder head. A thermal barrier coating is inlaid in the pocket. The thermal barrier coating includes a ceramic-metallic layer directly coating the recessed pocket surface and a ceramic layer directly coating the ceramic-metallic layer and including an outer surface facing the combustion cylinder.

An apparatus for a combustion cylinder of a reciprocating piston engine includes a combustion cylinder end face component including a first side configured to face the combustion cylinder and extending in a radial direction of the combustion cylinder and a pocket recessed into the first side and including a recessed pocket surface. The combustion cylinder end face component may be one of a piston and a cylinder head. A thermal barrier coating is inlaid in the pocket. The thermal barrier coating includes a ceramic-metallic layer directly coating the recessed pocket surface and a ceramic layer directly coating the ceramic-metallic layer and including an outer surface facing the combustion cylinder.

A film forming method forms a coating film on a workpiece (e.g., a cylinder head) having a film-deposited portion (e.g., an annular valve seat part) by moving a nozzle of a cold spray device relative to the workpiece along a film formation trajectory having a film formation starting point and a film formation finishing point in which the film-deposited portion overlaps to form an overlapping portion. The coating film is formed by causing a raw material powder to collide in a solid-phase state with the workpiece and plastically deform. Also, the coating film on the film-deposited portion is further formed such that an inclination angle of an end part of the coating film relative to a surface of the film-deposited portion is 45° or less at the film formation starting point of the overlapping portion.