Flank wear and machining performance of cryogenically treated tungsten carbide inserts

Abstract

Cryogenic treatment has been accredited as a means of enhancing the cutting life of tungsten carbide turning inserts. Most of the research conducted till date has been limited to evaluate the percentage improvement in tool life of cryogenically treated tungsten carbide inserts but no sincere efforts have been made to excavate the mechanism responsible for this improvement. In order to understand the mechanism accountable for enhanced tool life of tungsten carbide inserts, a comparative investigation of the wear behavior and machining performance of cryogenically treated tungsten carbide inserts in orthogonal turning has been carried out in this study. The commercially available uncoated square shaped tungsten carbide inserts (P25) were procured and subjected to cryogenic treatment at two levels −110 C (shallow treatment) and −196 C (deep treatment) of temperature independently. The criterion selected for determining the turning performance was based on the maximum flank wear (0.6 mm) as recommended in ISO 3685-1993 and surface roughness Ra of the workpiece. The results showed that cryogenically treated tungsten carbide inserts performed significantly better as compared with untreated ones. Also, a substantial increase in tool life was recorded in deep cryogenically treated (DCT) inserts as compared to shallow cryogenically treated inserts (SCT).