Experimental assessment of self-healing nature in aluminum-based smart composites with NiTi wires and solder alloy as healing agents through Taguchi approach

In this article, the healing assessment of the AA2014 matrix reinforced with NiTi wires and solder alloy as healing agents is investigated through flexural testing. The idea of a smart composite was such that it could retain its structural stability through NiTi wires reinforced, which ultimately heals the macro cracks, whereas the solder alloy binds the micro-cracks by filling through the gap after heat treatment. The objective of this work is to determine the parameters influencing self-healing assessments. Specimens with different shape memory alloy vol% (0.5%, 1.3%), specimen size (1, 2) and shape memory alloy wires diameter (0.47 mm, 0.96 mm) were fabricated for analysis. Furthermore, Taguchi orthogonal columns of L8 (4^1 2^3) array technique was implemented to study the observations from different experimental runs. Healing temperature (i.e. 600°C) was selected such that it could take advantage of the compositional healing of the matrix. The completely damaged specimens through the bend test were thermally treated at different healing durations (30, 60, 90, 120 min) in a furnace to activate healing. The results show that a maximum of 96.95% of crack depth, 100% of crack width, and 73.76% of the recovery in flexural strength was recovered after heat treatment.