Continuous fiber reinforced metal matrix composites (CFMMCs) show great potential in aerospace industry due to their high specific strength, excellent high-temperature resistance, improved fatigue performance, and lightweight properties. Grinding plays a pivotal role in machining difficult-to-cut materials, including ceramic composites and metal matrix composites. However, the process often results in severe surface defects, such as matrix smearing, fiber fragmentation, and delamination, due to the high toughness of the metal matrix, the high hardness and brittleness of reinforcing fibers, and the inherent anisotropy and heterogeneity of composites. This study employs high-speed grinding (HSG) with single-grain abrasives to process SiCf/TC17 composites, aiming to improve the removal of matrix and fibers. Furthermore, this study investigates the coupled removal mechanisms of the matrix and fibers at various fiber grinding orientations, as well as the effects of grinding speed and maximum undeformed chip thickness (agmax) on material removal behaviors. Results show that fiber properties significantly influence the removal mechanism more than grinding direction. Cracks in fibers propagate perpendicularly to the tungsten core or radially. Increasing grinding speed from 30 m/s to 120 m/s while agmax=0.3 μm reduces matrix smearing and plastic flow traces, while HSG effectively mitigates large-scale fiber fragmentation. When vs=80 m/s, reducing agmax from 0.8 μm to 0.1 μm significantly enhances fiber removal quality by transitioning from large-scale fragmentation or fracture to micro-fragmentation, thereby substantially reducing matrix smearing defects on the machined surface.
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