A novel shape-curved tool design aiming at high-quality blisk root-fillet surface polishing

We designed a novel shape-curved tool shaft to promote interference avoidance in polishing root fillets of aerospace blisks, enabling a reduction in surface partitioning to eliminate connecting polishing marks by expanding the interference-free space for toolpath planning. To this end, a toroidal space is novelly proposed for incorporating interference-free feature analysis with respect to tool shape variations at given tool contact points. Specifically, the conceptual design of a shape-curved tool (SCT) is introduced first, applying a curved tool shaft to expand its interference-free feature, followed by a detailed parametric design and modeling of the SCT by considering several critical criteria: local gouge and global collision, effective polishing wheel radius, and continuous toolpath. The interference-free space (IFS) at successive tool contact points is calculated and projected onto the proposed toroidal space to illustrate the interference feature, enabling the IFS connectivity analysis regarding the influence of the tool design parameters. Finally, an aero-engine blisk polishing experimental trial was conducted and analyzed to validate the feasibility of SCT with the aim of establishing a benchmark for high-numbered blisk polishing.