Experimental Study on the Surface Densification of Fe-2Cu-0.6C Powder Metallurgy Material

The present work investigated the effects of rolling force (longitudinal feed) and spindle speed on surface performance of Fe-2Cu-0.6C powder metallurgy material. A newly self-designed rolling tool was used to densify the material's surface, and then the surface properties were measured. Results indicated that rolling force was the main effective parameter, and spindle speed was the secondary one. A densified depth and a surface hardness of 335 µm and 320 HV0.1 were obtained by using a rolling force of 2800 N and a spindle speed of 360 r/min. The tensile strength was improved by 75%. The tensile fracture had mixed-rupture characteristics of dimples and tear ridge. In the surface layer, the ferrite was stretched and refined. The pearlite was deformed and oriented along the rolling direction. The lamellar spacing close to the surface was reduced. It played a significant role in enhancing the strength of material.