Design and Development of Shape Memory Alloy Actuator for Preventing and Protecting Electrical Wires

Abstract

Fatigue failure of wires is a frequent issue that evolves over time as a result of utilizing the profile under variable stress and temperature. In this article, an innovative study makes it possible to propose a protective tool for metal profiles against fatigue using shape memory alloys (SMA). Smart actuators like SMA are able to push back sudden stresses above the elastic limit, therefore, are characterized by high resistance to fatigue and even against corrosion due to their strong thermomechanical coupling. Besides, the study provides the results necessary to add a layer based on the shape memory tube to protect the important connectors for industrial systems and automotive industries. The conductivity of electrical current in various electronic devices depends on the copper material, which is good at conducting electricity and heat but weak against mechanical forces and hence easily susceptible to fatigue. Thereby, the elastic regime of copper is different from that of SMA, and in order to adapt the properties of two materials, a mathematical study can describe the behaviour of two combined systems is important for the analysis of the cyclic effect and for adapting the proposed actuator in wiring technology. Therefore, the study shows the great potential of the proposed SMA tube with its superelastic behaviour to increase the predicted lifespan of metallic wires against corrosion and fatigue. The lifetime of the conduction system with the protective SMA is increased remarkably and can reach up to 105cycles under the action of the stress of an amplitude of 550 MPa, the finite element simulation shows that the system of SMA combined with a 4 mm wire undergoing significant stress up to 490 MPa that can reach a deformation of 7% and return to the initial state without residual deformation. The simulation's results look at the evolution of stress, strain, fatigue lifetimes, and anticipated damage, and they match the experimental results of SMA tube properties rather well. Consequently, the verification of the proposed model confirms the improvement in the lifespan of studied wires compared to wires without SMA encapsulation.