A new compliant polishing method using 3D-printed elastic polishing tool with TPMS structure

Abstract

Leveraging the advantageous properties of Triply Periodic Minimal Surface (TPMS) structures, including tunable stiffness, lightweight design, superior heat transfer, and excellent energy absorption, this study utilizes 3D printing technology to develop a flexible polishing tool. The stiffness of the tool can be tuned by adjusting the type and relative density of the internal TPMS structures within the polishing head. Experimental and finite element analysis (FEA) were combined to simulate the compression behavior of TPMS lattice structures with different configurations and relative densities, revealing their tunable mechanical properties. Compression process simulations further revealed that an increase in relative density amplifies both the output pressure and its fluctuations, attributable to the distinctive structural properties of the architecture. Polishing experiments on K9 glass were conducted using the self-developed polishing tool on a robotic polishing platform, with processing performance evaluated through material removal rate, removal function, and surface roughness. Experimental results demonstrate the outstanding process stability and time-dependent controllability, achieving an average surface roughness Sa as low as 5.531 nm. The contact pressure critically influences the material removal rate, while pressure fluctuations from the internal TPMS structure affect surface roughness. The P-type structure, producing lower pressure, is ideal for fine finishing, whereas the higher-pressure D-type variant is better suited for coarse material removal. This novel tool provides a new pathway for ultra-precision machining applications.