Investigating the behavior of axial force and temperature in the drilling process of glass/epoxy composites with and without curvature

Fiber-reinforced composites are widely used in industries due to their high strength-to-weight ratio, high stiffness, and proper performance. One of the applications of composite laminates is fluid transmission by means of composite pipes. In this study, due to the increasing use of composite pipes, the effect of the main drilling parameters such as feed rate, rotational speed and tool diameter on the thrust force and temperature in the drilling of composite laminates with curvature was investigated and the results compared with one of composite laminates without curvature. To this end, glass fiber/epoxy composite laminates were manufactured by hand lay-up method. The experimental results show that, in general, in all diameters and feed rates, the thrust force in both composite laminates decrease with increasing rotational speed, but the effect of this parameter on temperature depends on the curvature of the composite laminates. Also, increasing the feed rate in both laminates increases the thrust force and decreases the temperature, and this is due to the increase of the pressure of the tool on the composite laminates and the reduction of the engagement time of the tool with the composite laminates, respectively. Finally, in general, the axial force and temperature in the same drilling parameters in the composite laminates with curvature is lower than that one without curvature.