Grof- en Ultrafijnkorrelige Fe- en Cu-gebaseerde Materialen onder Glijden: Evolutie en Stabilisatie van de Microstructuur onder het Oppervlak

This PhD research investigates how microstructural design and processing strategies can enhance the strength, stability, and tribological performance of metal-based materials subjected to reciprocating sliding. Modern engineering components—from aerospace actuators to precision mechanical systems—operate under demanding sliding contact conditions where friction, wear, and subsurface damage critically influence reliability and efficiency. Traditional alloy design has struggled to balance high strength with wear resistance, as hard materials often crack under cyclic loading while softer materials deform excessively. Recent advances in ultrafine-grained (UFG) metals offer a pathway toward improved mechanical performance, yet their behaviour under sliding remains insufficiently understood, particularly regarding subsurface microstructural evolution. This thesis addresses this gap by examining three representative material systems: pure Fe and Cu, Cu-Al₂O₃ metal matrix composites, and Fe-Cu immiscible alloys. Together, they capture the contrasting deformation mechanisms of BCC and FCC metals, the stabilizing role of ceramic dispersoids, and the effects of dual-phase architectures. The research aims to clarify how processing routes affect microstructure and strength, how friction and wear develop in each system, and how subsurface layers evolve during sliding. Ultimately, the work seeks to establish microstructural design principles for creating wear-resilient, high-strength metallic materials for advanced engineering applications.