The Effect of Tool Geometry on the Machinability of Polyamide During Precision Turning

Abstract

The cutting tool geometry plays a significant role on the performance of conventional machining operations, irrespectively of the work material. For instance, alterations in the cutting edge preparation will result in changes in tool wear rate, cutting forces, temperature, and machined surface finish. This article compares the performance of uncoated carbide tools with standard cutting geometry and tools with modified edge preparation during precision turning of polyamide with and without 30% glass fiber reinforcing. The results indicated that, in general, the turning force components are reduced with the tool nose radius and the specific cutting force (Ks ) decreased as feed rate is elevated, presenting values comparable to metallic alloys. In addition to that, the polyamide without reinforcing presented a three-fold increase in specific cutting force (Ks) compared with the reinforced composite. Finally, the surface roughness increased as feed rate is elevated and tool nose radius is reduced.