Experimental and numerical research on the effects of minimum quantity lubrication in thread turning of free-cutting steel AISI 1215

Abstract

As a heavy-load machining method, thread turning always requires high-performance lubrication to achieve high machining accuracy and good machined surface quality. Minimum quantity lubrication with good lubrication effects is used more and more widely in machining process for its eco-friendly and economical benefits. In this article, numerical simulations on minimum quantity lubrication flow field were first conducted by means of computational fluid dynamics, and the effects of minimum quantity lubrication in thread turning of free-cutting steel AISI 1215 were evaluated based on experimental method. The computational fluid dynamics simulation results show that the two vortexes existing in minimum quantity lubrication flow field and the micro oil droplets with high speed above 200 m/s help to enhance heat exchange and lubrication effect by improving the permeation of oil droplets into the cutting zone. The thread turning experiment results also show that the cutting forces with minimum quantity lubrication were reduced significantly, and good machined surface quality was achieved, as compared with dry cutting.