Development of a cutting force prediction model based on brittle fracture for C/SiC in rotary ultrasonic facing milling

Ceramic matrix composites of type C/SiC got paramount importance due to their special properties like high specific strength, high specific rigidity, high-temperature strength, and high wear resistance. Their applications are increasing rapidly for space, military, and aerospace industries. However, due to inhomogeneous, anisotropic and varying thermal properties of these composites, there are issues to achieve desired quality, high efficiency, and cost-effective processing in machining. In this regard, the cutting force is the most critical parameter which is required to be minimized for such composites to achieve better quality and minimum defects, especially in milling processes. In this research, brittle fracture approach was adopted and a cutting force model was developed from C/SiC composites for rotary ultrasonic face milling (RUFM) process. The experimental RUFM was carried out on C/SiC material and found that the cutting force decreased significantly with the increase of cutting speed, whereas the same was found increased with the increase of feed rate and cutting depth. By comparison of the experimental and simulation data of the cutting force, it was found that the errors are below than 10 % in most of the sets of parameters. The variation found is due to the heterogeneity and other complex properties of C/SiC composites. The developed cutting force model then further validated through another set of experiments, and the results were almost the same as before experiments. So, the cutting force model developed in this paper is robust and it can be applied to predict the cutting force and optimization of the process.