Constant-load adaptive belt polishing of the weak-rigidity blisk blade

Abstract

A thin-walled weak-rigidity blisk blade is constructed from heat-resistant, high-strength materials. It is thus difficult to use conventional processing methods and adapt to blisk-blade deformation (BBD) or inner stress in the manufacturing of a blisk blade, and to guarantee dimensional precision and surface quality. The present research improves the dimensional precision and surface quality by developing constant-load adaptive belt polishing (CABP) for the thin-walled weak-rigidity blisk blade. The paper illustrates the methodology of CABP and establishes an equation for micro-displacement in constant-load adaptive control. The motion mechanism and control model for the micro-displacement are then analyzed and optimized. Dimensional precision is guaranteed because the constant-load adaptive control adapts to the BBD and because the flexible nature of belt polishing avoids deformation in manufacturing. Additionally, a cubic boron nitride belt is used to realize high efficiency and accuracy in the manufacture of a thin-walled blisk blade. Finally, different methods of belt polishing are experimentally investigated to determine a method appropriate for polishing an aero-engine blisk. The experimental results show that CABP has advantages of dimensional precision and consistency of the surface quality over traditional belt polishing when the BBD is large.