Fabrication, testing, and microstructural analysis of nitinol-based self-healing metal matrix composite of A356 alloy cast by semi-solid metal processing

Abstract

ABSTRACT The self-healing of metallic material is a relatively new area in materials engineering. It is inspired by the biological process of healing. This work analyzes the self-healing behaviour of metals-matrix composite. The semi-solid metal processing technology was opted to prepare an aluminium-based self-healing metal-matrix composite. Nitinol is the alloy produced by combining nickel and titanium in a 1:1 ratio, with the wires of the same incorporated within the aluminium matrix during the process. Analysis of the recovery rate of the self-healing material and microstructural investigation of the metal matrix composite is the objective of this research work. The deployment of shape memory wire provides the ability to recover the matrix material even from plastic strain. Nitinol exhibits a shape memory effect by the transformation of the phase. Integration of A356 alloy with nitinol wire enables the material to regain its original shape and dimension by heat as an external stimulus. Semi-solid metal process via rapid slurry formation technique handled delicately so that self-healing effect should not diminish. Microstructural evaluation indicates fair integration of the reinforcement within the matrix material. Analysis of crack closure shows 44.277% positive recovery of the deformed surface.