Investigation of the cutting force and surface profile error when free form milling

Abstract

Machining free-form shaped surfaces is a widespread task. Aerospace, automotive, mould making and many other sectors are challenged by ever increasing demands for precision and economy. In ball-end milling, the constantly changing cutting conditions affect the shape and volume of the chip, as well as the tool load and the quality of the resulting surface. It is important to know the cutting force for a given surface characteristic, because this makes it easier to plan the machining process. The prediction of cutting forces is very important for optimising machining strategies and parameters to achieve the required accuracy. In the experiments, the forces on the tool and the surface geometric accuracy were measured by milling test surfaces of 42CrMo4 with different cutting parameters. Based on the measured values, the average cutting force was determined, the variance of the force variation was investigated and the force momentum, which takes into account the machining time. The aim of this paper is to investigate and compare the cutting force and the surface profile error of the resulting surface during finishing milling with a ball-end milling cutter.