Performance of cutting fluids during face milling of steels

An experimental investigation on the performance of an emulsion of mineral oil, semi-synthetic and synthetic cutting fluids when face milling AISI 864 0 steel with coated cemented carbide tools were carried out. Dry cutting wa s also performed for comparison purpose. Tool life, power consumption and s urface roughness were monitored during the machining trials. In order to st udy the cooling ability of the cutting fluids, cutting temperatures were me asured during turning of AISI 1020 steels, using the tool-workpiece thermoc ouple method. The highest cutting temperatures were generated when machining dry, followe d in a decreasing order, by the application of the synthetic, emulsion of m ineral oil and semi-synthetic cutting fluids. A reverse effect was found in terms of the power consumption during machining. The best tool life was re corded when machining dry, followed, in a decreasing order by the applicati on of synthetic and semi-synthetic cutting fluids. Comb cracking was the ma jor failure mode of the cutting inserts during machining. Dry machining pro duced slightly better surface finish than machining in the presence of cutt ing fluid. (C) 2001 Elsevier Science B.V. All rights reserved.