A comprehensive investigation into the influence of variation in the stacking sequence on the mechanical behaviour and drilling machinability of basalt fiber-reinforced composite tubes

In composite materials, stacking of layers at different angles and changes in stacking sequence significantly affect not only the mechanical behavior but also the machinability characteristic of the composite structure. Therefore, the variation in stacking sequence represents a recent and important research topic in fiber-reinforced plastics. The objective of this study was to investigate the mechanical properties and drilling machinability characteristics of BFRP composite pipes in three different stackings: [±30/±60/±90]3, [±60/±90/±30]3 and [±90/±30/±60]3. The experimental results demonstrate that the stacking sequence has a significant effect on the mechanical behavior and drilling-induced damage formation. It is determined that the [±90/±30/±60]3 sample provided the highest performance in terms of mechanical properties but increased the thrust force during drilling. Furthermore, it is observed that the positioning of the ±90 layer has a considerable impact on both the mechanical and machinability outputs. © 2025 Elsevier Ltd