Abstract
Machining of carbon fibre reinforced polymer (CFRP) composites is challenging due to their inhomogeneous and anisotropic structure as well as the strong effect of the carbon fibres on wear. Burrs are critical machining-induced macro-geometrical defects in the case of the machining of CFRP composites, which may lead to assembly difficulties. Nowadays, although novel hole-machining technologies reduce the likelihood of burrs occurring, these technologies are often more costly and require longer machining times. The current experimental study focuses on the analysis of burrs induced by advanced hole machining technologies (helical milling, tilted helical milling and wobble milling) and comparison with a conventional one (conventional drilling).A total of 32 experiments were carried out in a VHTC 5-axis machining centre using uncoated solid carbide end mills. Furthermore, these technologies are compared and discussed based on the burrs experienced and average material removal rate (AMRR). Experimental results show that conventional drilling caused the lowest amount of burrs, followed by wobble milling, tilted helical milling and helical milling. Even though wobble milling is one of the most advantageous technologies in terms of burrs, the AMRR of conventional drilling is twenty times larger than that of wobble milling, therefore, the further development of wobble milling is recommended.
Highlights
Nowadays, the demand for fibre reinforced polymer composites is increasing and their key role in industry is undeniable
Helical milling resulted in the greatest amount of burrs, contradictory to the statements made by Denkena et al [5] as well as Eguti and Trabasso [7] that helical milling can yield less burrs compared to conventional drilling
The length of burrs was less than 1 mm for holes machined by conventional drilling and wobble milling, while the length of burrs in holes machined by tilted helical milling exceeded 2 mm at all settings
Summary
The demand for fibre reinforced polymer composites is increasing and their key role in industry is undeniable. CFRPs possess larger strength-to-weight ratios compared to metals, making them exceptionally suitable for parts built into assemblies connected to the aviation, aerospace and automotive industries, reducing fuel consumption [2, 3]. They exhibit good levels of corrosion resistance and are very strong as well as stiff. CFRPs are difficult to machine, since the carbon fibres significantly contribute to tool wear as well as make the material anisotropic and inhomogeneous. Since the present of burrs renders post-machining almost inevitable, in order to reduce the resources necessary for further manufacturing
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
