An evaluation of micro milling chip thickness models for the process mechanics

An accuracy of the chip thickness models used in the micro milling mechanics models directly affects the accuracy of the cutting force predictions. There are different chip thickness models derived from various kinematic analyses for the micro milling in the literature. This article presents an evaluation of chip thickness models for micro milling by examining their direct effects on predictions of cutting forces. Performances of four chip thickness models for micro milling existing in the literature are tested and compared with the experimental force measurements. Micro end milling experiments were conducted on an aerospace-grade aluminum alloy Al7050 for different feed rate values. The root mean square deviation and the coefficient of determination values between the estimated and measured micro milling forces are presented for the comparative evaluation of the major chip thickness models at various feed per tooth to tool diameter ratios.