An experimental investigation of the effect of coating material on tool wear in micro milling of Inconel 718 super alloy

In this study, milling of the 718 nickel super alloy in micro conditions and the effect of coating material on tool wear are investigated. Within this context, coated and uncoated WC-Co micro milling tools were used for cutting experiments under dry and lubricated (minimum quantity lubrication, MQL) conditions. Tool wear occurred on the micro end mill, and the change in radius of the cutting tool and the side-edge radius were determined in accordance with the processed slot geometry. The results obtained showed that the cutting tools coated with AlTiN, TiAlN+AlCrN, and AlCrN displayed better performances compared to those coated with TiAlN+WC/C and DLC. In addition, DLC and TiAlN+WC/C coated tools showed better performance against built-up edge (BUE) formation. Furthermore, the MQL method used during the cutting process significantly reduced the decrease in the radius.