Integrated Design and Performance of Composite Springs: A Review
Abstract
Modern engineering increasingly requires lightweight, high-efficiency spring systems to optimise energy use, durability, and packaging within transportation and compact mechanical assemblies. However, composite-spring research remains fragmented across various spring types, material systems, modelling approaches, and manufacturing routes; this fragmentation hinders the translation of promising demonstrations into reliable components. This article provides a unified and critical synthesis of composite springs, covering leaf, helical, Belleville (disc), and wave configurations, and spanning macro-scale automotive structures through to space-constrained designs and structured/microstructured concepts. Rather than treating the literature as a sequence of isolated case studies, the review interprets the field through a coupled material-architecture-geometry-manufacturing-readiness framework. This framework links reinforcement type, laminate/textile architecture, spring geometry, stress state, manufacturing defects, and qualification maturity to key performance outcomes, including stiffness, fatigue resistance, damping, mass reduction, energy storage, and durability. Material choices are evaluated not only in terms of reported performance gains, but also according to scalability, damage mechanisms, reliability limits, and unresolved design trade-offs. Furthermore, the review examines the numerical toolkit that underpins performance prediction, specifically laminate/analytical formulations, finite-element modelling, and optimisation for stiffness, fatigue, and energy dissipation. Building on this classical foundation, the discussion maps how additive manufacturing and metamaterial concepts expand the design space via topology freedom, tuneable nonlinear response, and multifunctionality, while also identifying their current limitations in qualification, repeatability, defect control, and validated multiscale models. The findings emphasise the necessity of integrated material-structure-process design, standardised testing, and digital-twin-enabled workflows to accelerate the dependable adoption of composite and architected spring technologies.