SMART MATERIALS FOR ADAPTIVE MECHANICAL STRUCTURES

Abstract

Smart materials — including shape memory alloys (SMAs), piezoelectric ceramics, magnetostrictive materials, and electroactive polymers — have revolutionized adaptive structural systems by enabling real-time tunability of geometry, stiffness, and dynamic response. Adaptive mechanical structures integrating these materials can self-sense and self-actuate under external stimuli such as temperature, stress, electric fields, and magnetic fields, facilitating applications in aerospace morphing systems, vibration suppression, and structural health monitoring. This article presents a comprehensive investigation into the mechanisms, design methodologies, performance evaluation, and comparative advantages of key classes of smart materials in adaptive mechanical structures. A mixed computational–experimental methodology is outlined to characterize actuation strain, response speed, energy efficiency, and durability. Results demonstrate that SMA actuators provide high actuation forces with significant strains, while piezoelectric materials excel in high-frequency vibration control. Magnetostrictive and polymer-based smart materials provide complementary adaptive functionalities. Integrating sensors, actuators, and feedback control is shown to enhance performance and resilience. Discussion contextualizes findings within prior studies, identifies current limitations (e.g., fatigue and control complexity), and outlines future research directions, particularly in multi-functional smart composites and 4D printed adaptive systems.