Thermal expansion of pre-deformed, short fibre reinforced Mg-based composites

Thermal expansion characteristics of the pure Mg, AS21 alloy, Mg-30 vol% Saffil fibres and AS21-25 vol% Saffil fibres composites were measured in the temperature range from 20 to 380 °C. All materials were studied in the as-prepared and the pre-deformed state. The dilatation thermal strain was obtained from the measured relative elongation and the relative elongation calculated from the rule of mixtures. The residual strain results in the permanent length change of the composite samples after the first thermal cycle. This change is influenced by the thermal and mechanical history of the composite, especially by the fabrication cooling or cold pre-deformation. The pre-deformation of the alloys and composites influences the coefficient of the thermal expansion.