An experimental study of cutting fluid effects in drilling

Experiments were designed and conducted on aluminum alloys and gray cast iron to determine the function of cutting fluid in drilling. The variables examined included speed, feed, hole depth, tool and workpiece material, cutting fluid condition, workpiece temperatures and drill geometry. The experimental responses under consideration were quantitative as well as qualitative. The quantitative responses included drilling torque, thrust force, hole quality (diameter, perpendicularity, taper and cylindricity), surface finish and built-up edge, whilst the qualitative responses were chip morphology and inspection of hole side-walls. The results indicate that the cutting fluid does have an effect on the surface finish, and that the cutting fluid interacts with other variables to have an effect on hole quality. The evidence suggests that the mechanism of the cutting fluid is lubricating at the margins of the drill. (C) 1997 Elsevier Science S.A.