Fabrication and characterization of aluminum - magnetic shape memory alloy composites

Smart composites, manufactured with embedded functional materials, hold the potential for a new type of structural health monitoring systems. The work herein focuses on how embedding Ni43Co7Mn39Sn11 metamagnetic shape memory alloy (MMSMA) sensory particles into pure aluminum matrix modifies chemical constitution and mechanical properties both materials. Martensitically transforming in Al or alloys can interact crack tip stress fields undergo stress-induced martensitic transformation. This process emits acoustic signals changes magnetic state particles, which then be exploited using monitors and/or sensors to determine locations. Fabrication these composites consisted consolidation homogeneously mixed powder precursors containing 10 vol% MMSMA particles. Elemental composition, hardness, elastic modulus resulting diffusion region between were determined wavelength dispersive spectrometry instrumented nanoindentation. Elastic constants sintered bulk also experimentally resonant ultrasonic spectroscopy (RUS). Compositional analysis revealed that contained diverse group intermetallics. Nanoindentation results demonstrated exhibits high hardness value 10.0 ± 0.3 GPa an 163 5 GPa, as compared having 4.5 0.4 127 6 GPa. Poisson's ratio stiffness tensor components (C11, C12, C44) found 0.34, 214 111 52 respectively, through RUS. important material present study, especially interface properties, used model composite system optimize particle size, distribution, size interfaces desired damage sensing ability.