An extensive review of the water consumption and cutting fluid based sustainability concerns in the metal cutting sector

Machining processes consume natural resources as input streams and generate intense heat during the cutting process due to excessive shearing caused by plastic deformation and friction. The excessive amount of heat generation in the cutting zone can impair the machining performance and service life of the product by reducing the tool life, disturbing the surface integrity and dimensional tolerancing of the machined part. Due to the consumption of natural resources and generation of waste output streams, sustainability of machining process is questioned. Application of cutting fluid in machining processes is considered as one of the major contributor towards higher environmental impact. Despite of their disposal problem, cutting fluids involve generous amount of water for their preparation. The current study aims to provide a systematic, critical and comprehensive review about the following objectives; (1) water demand in machining, and (2) progress of different environment friendly lubrication/cooling strategies. For the first research objective of water demand in the machining processes, the study presented a thorough start-of-the-art about the water foot print involved in the machining processes. For the second research objective, different environment friendly lubrication and cooling strategies were critically discussed based on the solution provided by different metal cutting studies. For this purpose, studies from the last couple of decades were given a special consideration. The study also includes the influence of cutting parameters and different nature of machining processes such as milling, turning, drilling and grinding etc. under different green lubrication and cooling strategies. Finally, the study concludes the potential solutions to replace conventional cooling methods, and recommends future directions based on their associated current challenges.