Effect of Chip Segmentation on Cutting Forces at High Speed Milling of Al Alloys

Abstract

In this paper, an experimental study was performed to investigate the chip formation on cutting forces on aluminum alloy at different heat treatment states. Heat treatment (precipitation hardening) of Al-Si-Mg-Fe alloy is the essential parameter for continuous or segmented chip formation. Cutting speed and feed per tooth are the only cutting parameters with influence on the degree of segmentation in microstructures, leading to chip segmentation. Increasing cutting speed or feed per tooth leads to a more severe segmentation of the chips obtained from underaged material. While the chips obtained from overaged material remain continuous up to the highest cutting speed investigated. This investigation confirms that precipitation hardening is the key in changing from continuous to segmented chip formation and not only the cutting parameters. When machining the underaged microstructure, the degree of segmentation increases with a constant slope upto 7000 m/min cutting speed. This study concludes that the relationship between chip formation and cutting forces using HSM.