Effect of fibre content and notch radius in the fracture behaviour of short glass fibre reinforced polyamide 6: An approach from the Theory of Critical Distances

This paper presents an analysis of the notch effect on the fracture behaviour of short glass fibre reinforced polyamide 6 (SGFR-PA6) with different amounts of fibre content. The research is based on the results obtained in an experimental programme composed of 125 fracture specimens, combining five different fibre contents and five different notch radii. Concerning the apparent fracture toughness, a clear notch effect has been observed, with an increase in the fracture resistance when the notch radius increases. Moreover, the apparent fracture toughness has been reasonably predicted through the Theory of Critical Distances. The results have also shown a direct relation between the apparent fracture toughness and the fibre content. The research is completed with the Scanning Electron Microscopy analysis of the evolution of the fracture micromechanisms when both the notch radius and the fibre contents increase.