Evaluation of Surface Roughness in High-Speed Shaping of Ni-P

Abstract

A flat surface was machined by shaping to investigate the influence of the cutting speed on surface finish. When the cutting speed was 10-30 m/min, the surface roughness deteriorated because fine valleys with a depth of 40-200 nm were caused. Because the pitch of the valleys was almost equal at different cutting speeds, it was concluded that the valleys were not caused by the natural vibration of the machine tool. The velocity of the tool tip was measured by a laser Doppler vibrometer to compare the tool motion and the work piece profile. The periodical velocity change of the tool corresponded to the pitch of valleys. When a work piece with higher phosphorus content was machined, the valleys were not caused at a cutting speed of less than 30 m/min. It is estimated that the smoothness of chip removal has an influence on the emergence of valleys.