Abrasive flow polishing of impellers

Aero-engines are hailed as the "jewel in the crown" of high-end manufacturing, and the machining quality of integrally bladed rotors (IBRs) directly determines the engine's thrust-to-weight ratio and operational performance. Research indicates that the machining quality of the leading and trailing edges of the blades can affect the aero-engine's boost efficiency by up to 5%. The polishing precision and surface quality achieved after finish-milling complex curved surfaces directly dictate the component's ultimate aerodynamic performance.

A rough impeller surface leads to a series of issues: increased airflow disturbance, higher fluid resistance, greater energy loss, and reduced fatigue life. Precision polishing significantly mitigates these problems. Experimental data show that abrasive flow polishing reduces surface roughness from an initial Sa of 0.76 μm to 0.30 μm—an improvement of 60%—and lowers the surface friction coefficient from 0.4281 to 0.3853. Furthermore, the wear mechanism shifts from adhesive and spalling wear to abrasive wear. Simultaneously, the material surface undergoes work hardening due to plastic deformation and grain refinement, resulting in significantly enhanced wear resistance.