Cooling and lubrication techniques in grinding: A state-of-the-art review, applications, and sustainability assessment

Grinding technology is an essential manufacturing operation, in particular, when a component with a superfinishing and an ultra-resolution is yearned. Meeting the required strict quality checklist with maintaining a high level of productivity and sustainability is a substantive issue. The recent paper outlines the lubrication and cooling technologies and mediums that are used for grinding. Furthermore, it provides a basis for a critical assessment of the different lubrication/cooling techniques in terms of machining outputs, environmental impact, hygiene effect, etc. Meanwhile, the paper put light on the sustainability of different cooling/lubrication strategies. The sustainability of machining aims to get the product with the best accuracy and surface quality, minimum energy consumption, low environmental impact, reasonable economy, and minimum effect on worker's health. The paper revealed that despite some cooling/lubrication mediums like mineral oils and semisynthetic, afford sufficient lubrication or cooling, they have a significant negative impact on the environment and public health. On the other hand, emulsions can overcome environmental problems but the economy and the energy consumption during grinding are still a matter of concern. Biodegradable and vegetable oils are considered eco-friendly oils, but they suffer from a lack of thermal stability which affects their ability of efficiently cooling. Using the cooling medium with the lowest amount can achieve the goal of the economy but it may be reflected negatively on the machinability. Furthermore, cryogenic lubrication doesn't provide sufficient lubrication to reduce friction and hence energy consumption. The research described in the paper is such a comprehensive compilation of knowledge regarding the machinability and machining performance under different cooling and lubrication systems that it will aid the next generation of scientists in identifying current advancements as well as potential future directions of research on ecological aspects of machining for sustainability.