Method of treating composite piston pin and surface treated composite piston pin

A method of treating a composite piston pin, comprising:

• preparing the composite piston pin of which at least a surface layer includes a composite material including a reinforcing fiber and a resin;
• improving roughness by processing the at least a surface layer of the composite piston pin;
• and
• forming a coating layer on the at least a surface layer processed to reduce a friction coefficient of the composite piston pin,
• wherein the preparing includes:
• a first rolling step of rolling a first prepreg including a reinforcing fiber and a resin to enclose an outside surface of a cylindrical mold;
• a second rolling step of rolling a second prepreg including a reinforcing fiber having elasticity higher than that of the reinforcing fiber of the first prepreg and a resin to enclose an outside surface of the first prepreg;
• and
• a molding step of putting the first prepreg and the second prepreg rolled on the cylindrical mold in an oven and integrally molding the first prepreg and the second prepreg,
• wherein the second prepreg configured to include the reinforcing fiber aligned in parallel with a longitudinal direction of the composite piston pin, and
• wherein the first prepreg includes:
• a first layer configured to include the reinforcing fiber aligned perpendicular to the reinforcing fiber of the second prepreg;
• a second layer configured to include the reinforcing fiber aligned in parallel with a longitudinal direction of the composite piston pin, and
• wherein a ratio between a thickness of the rolled first prepreg and a thickness of the rolled second prepreg is within range of 7:3 to 4:6.