No abstract

No abstract

This study makes a comparison between whisker-reinforced alumina and SiAlON ceramic tools in high-speed face milling of Inconel 718. A series of tests have been conducted, and the cutting forces, tool wear morphologies and tool failure mechanisms are discussed with regard to a wide range of cutting speeds (500-3000 m/min). Results show that the resultant cutting force of SiAlON ceramic tool KY1540 is much bigger than that of whisker-reinforced alumina ceramic tool KY4300 at the same cutting condition. For both kinds of tools, under relatively lower cutting speed, nose notch wear is the predominant failure mode affecting the tool life, while further increase in the cutting speed, notch wear at the depth of cut becomes the determining factor. KY1540 shows a better notch wear and thermal shock resistance than KY4300. The tool failure mechanisms involve notching, microcracks, chipping, flaking, adhesion and oxidation wear. Better surface quality can be got using KY4300 ceramic tools.

This article presents the development of a three-dimensional finite element model to simulate the high-speed end milling of Ti-6Al-4V titanium alloy based on the commercial finite element package Abaqus/Explicit. The Johnson–Cook material constitutive model was employed to model the flow stress behavior of the workpiece. Zorev’s friction model was used to determine the frictional behavior of the tool–chip interface, and Johnson–Cook shear failure criterion was used to realize chip separation. Based on the three-dimensional finite element model, cutting forces in three directions were predicted under different cutting conditions, and chip evolution and morphologies of different cutting parameters were also analyzed. Corresponding high-speed end milling tests were conducted, and cutting forces were measured using a piezoelectric dynamometer in order to validate the finite element model. The simulation results demonstrate an acceptable agreement with experimental results in both the chip morphologies and cutting forces in the range of cutting speed and feed rates considered.

No abstract

No abstract