Experimental investigations and sustainability analysis on the performance of vegetable oil-based MQL drilling of SS316L

Recently, efforts have been made to reduce the use of conventional cutting fluids. Minimum Quantity Lubrication (MQL) has become a favourable approach to enhance machining performance and sustainability. This study investigated the impact of various cutting conditions on the drilling performance of SS316L, considering surface roughness, tool wear, and chip forms. The drilling tests are performed under dry, flood, and vegetable oil-based MQL (VMQL) conditions. The drilling under the VMQL condition resulted in a desirable surface finish, as indicated by a lower Ra value of 1.81 mu m for 20 holes drilled compared to the other conditions. The results highlighted the efficacy of VMQL in reducing tool wear during drilling. Furthermore, the analysis of chip quality demonstrated that VMQL produced favourable chip forms compared to flood cooling and dry machining. The enhanced lubricating and cooling mechanism enabled the creation of desired chip forms under VMQL. In summary, the study clarified the specific benefits of different machining conditions, highlighting the crucial importance of lubrication in achieving desired surface finish, chip quality, and tool wear in various machining environments. The sustainability assessment is conducted using the Pugh matrix approach, and the superiority of VMQL over other drilling conditions is found.