Finite Element Investigation and Optimization of Tool Wear in Drilling Process of Difficult-to-Cut Nickel-Based Superalloy using Response Surface Methodology

This research deals with monitoring tool wear through the chip formations, forces, and edge temperature of drill while drilling in superalloy plate to optimize effective parameters which lead to facilitate machining process to improve tool life, and enhance productivity. Inconel 718 superalloy material, and cemented coated carbide tool were selected in this study to investigate tool wear mechanism. Mathematical models were deduced by Minitab software to display the influence of the main cutting variables such as cutting speed, feed rate and tool diameter on tool wear. A wear process model of twist drill is established based on finite element method. The 3D FEA model established here provides a new approach to study the mechanism of drill wear. The predictive models in this study are believed to produce values of tool wear close to those readings recorded experimentally with 95% confidence interval, verified using ANOVA. The simulation results were in accordance with experimental and predictive values from RSM with error rate of 4-6%, proving the ability of the tool wear model to correctly forecast it. In addition, the experimental results demonstrated that cutting speed as the main parameter followed by feed rate, contribute significantly the tool wear of drill bit.