Two Reasons for the Formation of Surface Roughness in Precision Parts Processing

In the process of precision parts machining, due to the residual area caused by the geometric shape and cutting motion of the tool, the grooves scratched by the chip accumulation on the tool edge, the vibration ripple caused by the vibration between the workpiece and the tool, and the extrusion and friction marks caused by the wear of the tool back surface during the cutting process, roughness is formed on the surface of the part. The process factors that affect surface roughness include workpiece material and cutting amount.

Generally, elastic-plastic materials with higher toughness have higher surface roughness values after precision parts processing, while elastic-plastic materials with lower toughness are prone to obtaining lower surface roughness values after processing. For the same material, the larger the grain structure, the greater the machined surface roughness value. Therefore, in the process of precision parts machining, in order to reduce the surface roughness value, the material is often quenched and tempered or normalized before cutting to obtain uniform and dense grain structure and larger hardness.