Functionally graded Al–Al3Ni in situ intermetallic composites: Fabrication and microstructural characterization

Functionally graded materials (FGM) are a relatively new class of inhomogeneous composite materials, where the composition or the microstructure is locally varied to alter the material properties within a component. The present investigation is on fabrication of functionally graded Al–Al3Ni in situ intermetallic composites and their characterization. Al–Ni alloys with varying percentage of nickel (10–40%) have been used to fabricate Al–Al3Ni FGM by vertical centrifugal casting. The microstructural characteristics and hardness profile of these FGMs have been evaluated. Amongst the four alloy systems studied, Al–20 wt%Ni gives the best graded microstructure.