Dry Machining of Inconel 825 Superalloys

The present work investigates application feasibility of PVD TiN/TiCN/TiN coated cermet and CVD Al2O3/TiCN coated SiAlON for dry machining of Inconel 825 superalloy. Machining performance is interpreted through cutting force magnitude, tool-tip temperature, and mechanisms of tool wear. Results are compared to that of CVD multi-layer TiN/TiCN/Al2O3/TiN coated WC-Co tool. It is evidenced that SiAlON tool generates lower cutting force but experiences higher tool-tip temperature than other two counterparts. Apart from abrasion and adhesion, carbide tool witnesses coating peeling and ploughing. In contrast, SiAlON tool suffers from inexorable chipping and notching. Wear pattern of cermet tool seems less severe than carbide and SiAlON. Chip's underside surface morphology appears relatively better in case of cermet tool.

PROCESS-PARAMETER OPTIMIZATION OF WEDM WITH INCONEL 825 ALLOY USING GRA

The process-parameter optimization of a wire electrical discharge machining (WEDM) process has been performed with an Inconel 825 alloy during taper profile machining. The input parameters have been considered at three different levels and the number of experiments to be performed was decided using Taguchi's Design of experiment (DOE). The output performances such as material removal rate (MRR), Surface roughness (SR) and taper error (TE) were considered simultaneously for the optimization process. The experimental results were analysed using Grey relational analysis (GRA) and the best experimental trial was identified based on ranking. The influence of the input parameters was analysed using the ANOVA technique. The regression equations to predict the output responses were formed using the experimental results and the correlation between the experimental and regression equation results.