Experimental investigations on heat generation and surface roughness during orthogonal machining of stainless steel using bio-based oil mql

Abstract

Machining of hard material at higher parameters level is in the need of recent machining requirements and hence tool wears out rapidly during these situations of product manufacturing. So, cutting fluids are utilized to intercept the friction, heat generation, and to extend tool life during manufacturing operation through its feature of heat absorption, lubrication, and cooling action. It is conceivable only when the volume and application method of lubrication is suitable to the operator, environmental friendly, and profitable to the manufacturing industry. Because the inappropriate amount and unsuited methodology of cutting fluid utilization lead to several health as well as environmental issues, such as skin diseases, asthma, rashes, and respiratory problems and further unproductive to the firm as well. Therefore, the selection of lubrication strategy has become more challenging in the present day machining environment due to the aforementioned facts and strict government policies related to pollution, water footprints, and energy consumption. In this connection, dry machining is a better choice to tackle these ecological issues, but again this option does not remain economical at higher extents of cutting speed in mass production. Under these circumstances, advance levels of cutting speed result in rapid tool wear, loss of dimensional accuracy and poor surface finish. Consequently, uneconomical machining at stated extents of speed-feed combination. Hence the need for cooling system persists which could be the panacea of machining scenarios. Henceforth, keeping in mind the drawbacks of dry machining and flood lubrication the minimum quantity lubrication was adopted in present investigation as a feasible alternative approach to the mentioned drawbacks. The experiment was performed on Stainless Steel AISI-202 at higher levels of speed-feed combination in dry and MQL environments. Heat generation was recorded with the aid of standard K-type thermocouple. Bio-based soybean oil droplet assisted with air jet was used for lubrication and cooling purpose. Experimental results exhibited that the MQL-assisted machining remarkably reduced the heat generation, surface roughness, and chip reduction coefficient as compared to dry machining. It was also concluded that MQL was proved the best lubrication method for obtaining desirable results in terms of economy, health hazards, and environmental safety as compared to dry machining.