Mechanical behavior of shape memory alloy fiber reinforced aluminum matrix composites

This study aims to investigate mechanical behavior of NiTi shape memory alloy (SMA) long-fiber reinforced aluminum (Al) matrix composites, experimentally and numerically. The composites with three different prememorized shapes of SMA fibers, which were straight-, wave- and rectangle-shaped fibers, were fabricated by powder metallurgical techniques. Three-point bending and tensile test results demonstrated that wave-shape SMA/Al composites showed the highest elastic modulus and strength, and wave-shape and rectangle-shape SMA/Al composites showed high Poisson's ratio (lateral to longitudinal strain ratio in elastic-plastic regime). The experimental results were examined based on finite element analysis (FEA). It was concluded that internal stresses in the composites, which were introduced during the fabrication processes, highly affected their subsequent mechanical behavior of the composites.