Vegetable Oil-Based Lubrication in Machining: Issues and Challenges

The use of vegetable oil as a replacement for conventional mineral-based lubricant has gained many interests in recent years from the machining industries. This is due to the problematic issues with the use of conventional mineral-based lubricant that can cause negative effects on the manufacturing cost, operators' health and the environmental. As vegetable oil is renewable, biodegradable, and non-toxic and has remarkable tribological characteristic from its triglycerides structure, it has been identified as the best replacement for mineral-based cutting lubricant. However, formulating vegetable oil into machining lubricant has its challenges where it must overcome its nature of poor low-temperature properties and low oxidative stability. Therefore, this paper will elaborate the present issues and challenges in formulating green machining lubricant using vegetable oil and its stand under sustainable machining. This includes the method and technique of formulating vegetable-based lubricant and the output performance obtained from vegetable-based lubricant under machining in comparison to the conventional mineral-based lubricant. The result shows that utilizing the vegetable-based lubricant at minimum quantity has comparable or better performance to conventional mineral-based lubricant in terms of surface finish. Therefore, the use of vegetable oil has its challenges and issues as machining lubricant, but it is one of the current best viable alternatives to the mineral-based lubricant in promoting sustainable machining.