Sustainable Enhancement of Brake Rotor Durability in Electric Vehicles: Challenges, Innovations, and Future Directions

The widespread adoption of electric vehicles (EVs) has brought about critical challenges in brake rotor performance, primarily attributed to the reduced reliance on conventional friction braking systems.This decreased usage, owing to the predominant application of regenerative braking, has inadvertently increased the susceptibility of brake rotors-particularly those manufactured from grey cast iron (GCI)-to corrosion and non-traditional wear mechanisms due to extended exposure to environmental elements.These challenges are compounded by the global imperative for sustainable transportation solutions, as emphasized in the European Union (EU)'s roadmap for climateneutral mobility.In this context, the development and implementation of sustainable strategies to improve the wear and corrosion resistance of EV brake rotors have become paramount.This review synthesizes recent advancements in environmentally conscious approaches, including the application of eco-friendly surface treatments, alloying modifications, microstructural engineering, and solid or dry lubrication techniques tailored for GCI rotors.The analysis extends to the evaluation of scalability, cost-efficiency, tribological stability, and environmental compatibility over the rotors' service life.Particular attention is devoted to emergent solutions such as bio-inspired multifunctional coatings, integration of intelligent condition-monitoring technologies, and rotor design optimized through data-driven predictive modelling.The necessity for robust life cycle assessments (LCA) is underscored, aiming to holistically quantify environmental impact from raw material extraction through end-of-life disposal or recycling.Key research gaps are identified, including the limited real-world validation of novel materials under EV-specific load profiles and insufficient understanding of synergistic degradation modes under mixed braking regimes.It is suggested that a multidisciplinary research agenda-merging materials science, tribology, electrochemistry, and intelligent systems-is essential to advance the next generation of high-performance, low-impact braking solutions.In doing so, a comprehensive framework for sustainable brake rotor innovation in EVs can be established, aligning material resilience with broader environmental and regulatory goals.