Effect of sintering stage in NiTi short-fibre-reinforced aluminium–silicon composites interface properties

This study is concerned with the influence of sintering stage duration on the interface load transfer capacity between NiTi fibres and AlSi matrix alloy and thus in the final composite strength. Short-fibre-NiTi/AlSi composites were produced by a pressure-assisted sintering process, under vacuum, for sintering stages of 20, 25 and 60 min. All the obtained composites, with different sintering stages, have shown the occurrence of load transfer from the matrix to fibres, indicating the development of an effective interface between fibre and matrix. Performed shear tests have shown a decaying of shear strength with increasing sintering stage, in the selected range of sintering times, with the lowest sintering time leading to higher properties. It was also concluded that with increasing sintering stage, the interface volume around the fibres increases and the load transfer capacity decreases.