Tribology in metal cutting

Abstract

This chapter revisits tribology tests in metal cutting in order to obtain new fundamental knowledge on friction and to understand which technical modifications and operating parameters need to be developed and implemented in order to obtain good estimates of the coefficient of friction. The methodology draws from the development of new equipment and testing procedures focused on the interaction between surrounding medium, surface roughness and freshly formed surfaces to the independent determination of the coefficient of friction. The assessment of the coefficient of friction obtained from experimentation with two of the most commonly utilized simulative tribology tests in metal working (pin-on-disc and ring compression tests) against that determined in orthogonal metal cutting conditions allows concluding that the former, performed in dry friction conditions with adequate control of surface morphology and under a protective shield of Argon, is capable of modeling contact with friction in close agreement with real metal cutting. The identification of operative testing conditions that are capable of merging the estimates of the coefficient of friction provided by the different tribology tests ensures a unified view of tribologists and metal cutting experts on the accuracy, reliability, and validity of simulative tribology tests for metal cutting applications.