Shape Memory Effect, Thermal Expansion and Damping Property of Friction Stir Processed NiTip/Al Composite

NiTi particles reinforced aluminum (NiTip/Al) composite was prepared via friction stir processing, eliminating interfacial reaction and/or elemental diffusion. The NiTip in the composite maintained the intrinsic characteristic of a reversible thermoelastic phase transformation even after heat-treatment. The shape memory characteristic of the NiTip decreased the coefficient of thermal expansion of the Al matrix, and an apparent two-way shape memory effect was observed in the composite. The composite owned a good combination of adjustable damping and thermal physical properties.