Thermal fatigue behaviour of a 2014/Al2O3-SiO2 (Saffil® fibers) composite processed by squeeze casting

Thermal fatigue behaviour of a 2014/Saffil composite has been investigated. This composite was produced by infiltration of preforms of Saffil fibers (Al2O3-SiO2 fibers) with a 2014 aluminium alloy (Al-4.7Cu-1.0Si-0.6 Mg). The composite samples, containing 13 vol.% of fibers, were sectioned and their microstructure was investigated by optical microscopy, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). Tensile tests, hardness and microhardness measurements were carried out. The fracture surfaces were examined by SEM. Dilatometry was used in order to measure the thermal expansion coefficient (CTE) and to evaluate the strength of matrix/fiber bonds.