Effect of Combination of Cutting Fluid Concentration and Workpiece in Alkaline Cutting Fluid on Tool Life

In recent years, there has been a growing demand to reduce the environmental impact of cutting workplaces. To solve this problem, a method has been devised to suppress the decay of cutting fluid and extend the service life of cutting fluid by usi ng alkaline cutting fluid, which is a mixture of cutting fluid and strong alkaline ionized water. The aim of this study is to investigate the effect of cutting oil concentration of alkaline cutting fluid on tool life for several workpiece materials such as SKD11, SUS304, and P20.The results showed that in the machining of SKD11 and SUS304, the tool life was shorter in alkaline cutting fluid compared to normal cutting fluid, and that in alkaline cutting fluid of the same pH, the higher the cutting fluid concentration, the longer the tool life tended to be. In P20 machining, tools lasted up to 114% (2.14 times) longer in alkaline cutting fluid than in normal cutting fluid, and the longer tool life was greater with higher cutting fluid concentra tion, but even oil-free cutting fluid (0% oil pH11) was found to have a 32% longer tool life effect.