This article presents the influence of machining conditions on typical process performance indicators, namely cutting force, specific cutting energy, cutting temperature, tool wear, and fine dust emission during dry milling of CFRPs. The main goal is to determine the machining process window for obtaining quality parts with acceptable tool performance and limited dust emission. For achieving this, the cutting temperature was examined using analytical and empirical models, and systematic cutting experiments were conducted to assess the reliability of the theoretical predictions. A full factorial design was used for the experimental design. The experiments were conducted on a CNC milling machine with cutting speeds of 10,000, 15,000, and 20,000 rpm and feed rates of 2, 4, and 6 µm/tooth. Based on the results, it was ascertained that spindle speed significantly affects the cutting temperature and fine particle emission while cutting force, specific cutting energy, and tool wear are influenced by the feed rate. The optimal conditions for cutting force and tool wear were observed at a cutting speed of 10,000 rpm. The cutting temperature did not exceed the glass transition temperature for the cutting speeds tested and feed rates used. The fine particles emitted ranged from 0.5 to 10 µm aerodynamic diameters with a maximum concentration of 2776.6 particles for those of 0.5 µm diameters. Finally, results of the experimental optimization are presented, and the model is validated. The results obtained may be used to better understand specific phenomena associated with the milling of CFRPs and provide the means to select effective milling parameters to improve the technology and economics of the process.

Aluminum alloys are widely used in several applications. Cast alloys are usually considered to be brittle materials leading to short chip formation during machining. Although they can be produced near net shapes, products made of these alloys very often require some machining. The purpose of this study is to evaluate the machinability of A319 and A356 under T0 and T6 conditions. The machinability was assessed during the dry drilling machining process, with the machinability indexes including the chip form, chip breakability, and the cutting forces. It was found that A319 and A356 exhibit different machinability behaviors, especially under the T6-condition in terms of force requirements, chip breakability, and chip segmentation. The chip grain size obtained by X-ray diffraction techniques was also studied and correlated to the machining conditions. It was also found that both the microstructure of the workpiece materials and the machining conditions significantly affect the chip formation mechanism, and so the machining parameters could therefore be selected to promote a chip form that is easily manageable in production.