A simplified approach to evaluating the thermal behaviour of surface engineered cutting tools

It is commonly accepted that both the wear and failure mechanisms which develop in cutting tools are predominantly influenced by temperature. In order to predict the wear and failure characteristics of a tool it is necessary to quantify the temperatures which develop during the cutting operation. In recent years, numerical calculating methods have been widely developed in most areas of engineering and have been used to determine the thermal behaviour of cutting tools. In general, the application of finite element and finite difference techniques has been successful, yet: still relies heavily on the accuracy of experimentally determined boundary conditions. If, however, for a given application, an approximate solution were all that was required to give an indication of the thermal behaviour, then a simplified approach could be applied which would realise savings of rime, money and would broaden the potential user base. The development of such a technique to determine the thermal behaviour of cutting tools is described, with particular reference to assessing the thermal behaviour of single- and multi-point cutting tools before and after the application of advanced surface engineered treatments. An extensive programme of empirical and analytical work has been undertaken at Sheffield Hallam University to study the performance, life and design characteristics of various standard and surface engineered single- and multi-point cutting tools. Data acquired from research programmes have been used to predict the temperatures generated along the tool/chip interface using standard analytical methods. A simplified application of finite element techniques has been used to simulate the mode of dissipation of this heat source. The current paper describes the approach with reference lu TiN-coated and standard production indexable inserts (single-point tool) and bandsaw teeth (multi-point cutting tool).