Performance Evaluation of Solid Lubricants under MQL in Hard Turning of EN-31 Steel Using Coated Carbide Inserts

The present work studies the application of a solid lubricant mixture like Graphite in SAE 40 oil and Boric acid in SAE 40 oil under MQL in turning of EN-31 steel. Boric acid and Graphite are mixed with SAE 40 oil separately and sonicated thoroughly. The prepared mixtures are used at the cutting zone for determining surface roughness and tool wear and in order to assess performance of the cutting fluid at the corresponding cutting conditions The experiments are conducted using design of experiments based on Taguchi method and analysis of results is carried out by ANOVA to find which of the process parameters has significant effect on Surface roughness and Tool wear Principal Component analysis integrated Taguchi method is used to obtain the optimal combination of input process parameters and their corresponding responses for both the conditions. It is observed that performance of Boric acid is better than Graphite in reducing Surface roughness and Tool wear of the machined surface