Mechanistic modelling for predicting cutting forces in machining considering effect of tool nose radius on chip formation and tool wear land

Abstract

Tool wear during machining has been seen to result in changes in tool geometry, which adversely affect the performance characteristic of the process. Various force models have been proposed to compensate for the tool wear and thus enhance the process performance. The study undertaken proposes a mechanistic model to predict the cutting forces based on three-dimensional cutting operations. The model has been developed for predicting forces due to chip formation and due to worn-out cutting tool including cutting tool nose radius. The force that has been predicted due to chip formation is a function of chip flow angle and equivalent cutting edge geometry. The prediction of force due to worn-out cutting tool is based on the actual chip-tool contact area and the rubbing force. The total force estimated has been further optimised to get accuracy in the model. Optimisation process is achieved by using a technique of order preference by similarity to the ideal solution. Results of the proposed force model have been experimentally validated as well as found to be in good agreement with the results of the force models proposed by Huang and Liang [39] and Chinchanikar and Choudhury [21]. Further, a regression equation has been developed in order to check the adequacy of the proposed model. The modelling approach proposed may be readily extended to other machining operations such as drilling and milling.