METHOD FOR SURFACE TREATMENT OF SKIRT SECTION OF PISTON FOR INTERNAL COMBUSTION ENGINE AND PISTON FOR INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To provide a piston allowing the lubrication layer of a resin coating with a low friction coefficient to be tightly adhered to the skirt section of a piston for an internal combustion engine, with low friction, superior wear resistance, and superior anti-seizing properties, and enabling the reduction of wear of a cylinder inner wall, even if the lubrication layer is separated or abraded.;SOLUTION: Metal or ceramic fine particles having an average particle diameter of 20-400 μm are injected with compressed air or compressed nitrogen as a mixture fluid onto the skirt section of the piston, made of an aluminum alloy and produced by a method such as casting or forging, at an injection speed of 80 m/s or more or at an injection pressure of 0.2 MPa or more to be collided with the skirt section, thereby uniformly making the microstructure of a piston base material fine-grained in a depth range of 1-15 μm from the surface of the skirt section and forming a modified layer with an activated surface. A lubrication layer is formed on the modified layer, for example, by applying a resin with a low friction coefficient, while a surface of the modified layer is being activated.;COPYRIGHT: (C)2010,JPO&INPIT