A Comparison of Parameters for the Machining of Gray Cast Iron

Abstract

Abstract This investigation was designed to compare several types of data as parameters for predicting cutting speeds for gray iron. A series of eleven irons, representing ranges of alloys, ferrite, graphite, and mechanical properties was used in the study. Cutting forces, power, and energy were determined from drilling and milling tests, and cutting speed - tool life lines were determined for each of the irons. Finally, correlations were attempted between the cutting speed (V20) for a 20-min tool life, and all other available types of information. The net result of this approach was a comparison of the relative reliability of the different types of data. This comparison showed that combined carbon, microhardness, and the nucleation or graphitizing tendency hold the greatest promise of developing into reliable parameters, while Brinell hardness, tensile strength, drilling forces, and milling power show little promise of providing useful information. This study was preliminary in nature and was intended only as a screening process for narrowing down the field for future investigations. Consequently, the correlations between cutting speed and combined carbon, microhardness, and nucleation tendency are undeveloped, and applications should not be attempted without further investigation.