Experimental Investigations and Regression Analysis based Mathematical Modelling for Tool Life under Minimum Quantity Lubrication

Machining is a complex phenomenon that deals with challenging aspects. As the manufacturing sector is looking forward to profitability through productivity without compromising the quality of the product, it adds a burden on the entire system of the machining process under consideration. The heat generated at the machining zone results in a savior impact on the machining quality of the end product, which can be minimized using the cutting fluids appropriately. Tool life is an important aspect in every machining operation which does not only define the cost associated with the machining but also plays a vital role in defining the quality product. At the extreme temperature machining operation wear rate of the tool is faster which could be resulted in uneven surface integrity of the material under consideration. The additional attributes like coating, cutting fluid, and machining environment surely add life to the tool for a longer run. Considering the sustainable machining need, dry and near-dry machining are the most attributed techniques to explore. In the current research work, the experimental investigations into tool life are studied along-with the mathematical modeling using regression analysis. Under the application of minimum quantity lubrication and dry machining; the turning of the hardened AISI 4340 material is performed at varying cutting conditions. The vegetable oils are compared against the synthetic oil for better performance evaluation. The results are inferred that the canola oil gives superior performance in comparison to soybean and coconut oil under the category of vegetable oils. While comparing the overall performance; synthetic oil shows the better performance over the vegetable oils under consideration. The significant improvement in tool life is observed under minimum quantity lubrication as compared to the dry environment; attributed to the combined effect of cooling and lubrication by the virtue of compressed air and cutting fluid respectively.