A comparison on Properties of Gudgeon Pin Parts Manufactured by Cold Extrusion and Machining Process

Gudgeon pin or wrist pin is a segment of rotary engines that exists in automobile industries all around the world. This pin experiences a complicated and semi-random fatigue loading with tribological contact. Mechanical properties and geometrical dimensions and tolerances of gudgeon pin can be affected by manufacturing process. In this article, two manufacturing processes (cold extrusion process and machining process) are utilized for the fabrication of gudgeon pins from 16MnCr5 steel bars. Tensile test, surface roughness, surface hardness and geometrical tolerances are measured and compared. The results show that gudgeon pins manufactured by cold extrusion process have notably higher tensile properties and surface hardness, better surface roughness and tighter geometrical tolerances than machining process. Microstructure study shows grain refinement due to cold extrusion process.