SIMULATION OF THE TRIBOLOGICAL BEHAVIOUR OF METAL-CUTTING TOOLS AND ANALYSIS OF THE FRICTION CONTACT REGION

摘要

Performing cutting tests can be time consuming and very costly, especially when expensive materials are being studied. Simulations can provide a way to preselect tool materials or coatings. This can reduce the time and cost associated with selecting or developing cutting tools for specific applications provided the conditions are accurately reproduced. The aim of this investigation was to use tribological tests, performed under realistic conditions, to understand and ultimately predict the performance of a coating in a machining operation. This study focuses primarily the wear mechanisms associated with adhesion in the seizure zone of the rake face. The tribometer used in this study was constructed as a modified Brinell hardness test with different tribo pairs tested both on the tribometer and then during a cutting test. The tribometer results were investigated using a scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDX). Tool wear during cutting was assessed by measuring the progression of flank wear at intervals during the cutting test. This study shows how AlTiN can be used to reduce friction, adhesive transfer and wear leading to an overall longer tool life when machining a commercial grade of Ti6A14V alloy. The results provide background on how the coating is contributing to the tool life improvement.