3D Microstructure Investigation of Wear‐Resistant Porous Polyimide for Aerospace Bearing Applications

The wear resistance of porous polyimide, a heterogeneous and anisotropic material, is strongly governed by its microstructure. This study combines 3D pore structure reconstruction from CT imaging with an innovative full‐component wear test to investigate the relationships among pore geometry, topological features, transport characteristics, and wear performance. The results reveal that wear resistance is determined by synergistic multi‐scale effects: optimal performance is achieved with pore radii concentrated in the 11–17 μm range, throat radii predominantly below 7 μm, a moderate coordination‐number distribution with a low proportion of high‐coordination pores (e.g., 10–12), and relatively low tortuosity. This synergy yields structural orderliness characterized by a low fractal dimension, leading to superior wear resistance. The work establishes a “geometry‐topology‐transport” co‐regulation model, offering a new strategy for designing the microstructure and wear performance of novel materials for long‐life aerospace bearings.