Milling technology for SiCp/Al composites precision devices: status and prospects

Due to their high specific strength, high specific stiffness, and excellent thermal conductivity, SiCp/Al composites are widely used in precision components for aerospace and electronic packaging applications. Milling is often employed as the final or near-final operation and is key to ensuring dimensional accuracy and surface integrity. However, the pronounced property mismatch between the particles and the matrix leads to challenges such as rapid tool wear and surface deterioration. Facing growing application demands, the development of efficient and high-quality milling technologies for SiCp/Al composites has become increasingly urgent. Most existing review papers either discuss multiple machining methods in a parallel and broad manner or remain limited to a linear framework that links process parameters to machining outcomes. Such generic structures dilute the in-depth discussion of the intermittent cutting characteristics specific to milling. They also make it difficult to perform mechanistic, direct comparisons between different milling processes. As a result, they fail to reveal the fundamental physical origins of differences in machining performance. To address this issue, this review proposes a three-level progressive logical framework of “material characteristics, material removal mechanisms, and machining performance” and provides a mechanism-oriented systematic review of the milling of SiCp/Al composites. First, the paper clarifies the relationships among fabrication processes, the effect of particles, and comprehensive performance. Then, at the mechanism level, it systematically organizes and compares the material removal behavior under different milling strategies. This comparison establishes an intrinsic mapping between material properties and removal mechanisms. On this basis, the paper further provides an in-depth analysis of how different machining parameters affect the milling performance of SiCp/Al composites. Finally, it identifies the key bottlenecks of current technologies and outlines research directions for achieving efficient, high-quality, and stable machining. These insights offer important theoretical guidance for process optimization and engineering applications.