Studying a grinding method of sapphire pipes using two grinders
This paper examines the thermophysics of a drilling process of polymeric composite materials such as carbonfibre-reinforced plastics (CFRP) and fibreglass by tubular diamond drill bits. Features of the COMSOL Multiphysics engineering software package were used. We employed Fourier heat equations, which express the intensity of heat gain by a mobile source in a moving coordinate system. The research was performed using the proprietary method of modelling spatial thermal action upon drilling polymer composite materials (fibreglass and carbon-fibre-reinforced plastics) in the COMSOL Multiphysics software environment. A tubular diamond drill bit with a diameter of 10 mm with two slots was chosen as a model cutting tool. Solid plates with a thickness of 5.5 mm made of layered fibrous polymer composite materials (fibreglass, carbon-fibre-reinforced plastic) were used as a preform. As a result of computer calculations, we obtained temperature fields of fibreglass and carbon-fibre-reinforced plastic during diamond drilling with the tubular tool. When studying the thermal behaviour of fibreglass and carbon-fibre-reinforced plastics, maximum temperature fields were located. The study revealed that the temperature reaches 413.6 K and 448.7 K during CFRP and fibreglass drilling, respectively. It was shown that the distance of heat transfer from the edge of the hole into the preform was 6.42 and 6.40 mm for CFRP and fibreglass, respectively. A method of modelling the thermal effects when cutting polymer composite materials developed in the COMSOL Multiphysics environment allows complex analytical calculations of temperatures induced by drilling to be simplified. In addition, it helps avoid overheating of a preform during drilling, allows the depth of heat distribution inside the preform from the edge of the formed hole in different polymer composite materials to be assessed. These measures lead to increasing the machining quality of polymer composite materials.