Performance evaluation of cryogenically treated tungsten carbide cutting tool inserts

This paper presents an overview of the effects of various subzero thermal treatments on the tool life and wear characteristics of cobalt-bonded tungsten carbide cutting tool inserts. The inserts were subjected to six different conditions of treatment, namely (a) as-received, (b) quenching treatment, (c) cryogenic treatment, (d) cryogenic treatment followed by tempering, (e) cold treatment and (f) cold treatment followed by tempering. It was found that the inserts that had undergone the latter four conditions of treatment exhibited significantly greater tool life and wear resistance at higher cutting speeds, as well as an overall increased resistance to chipping. Microstructural analysis was used to explain the observed phenomena.