High-precision complex structured Sm-PMN-PT ceramics with large piezoelectric response manufactured by vat photopolymerization

Sm0.025Pb0.9625[(Mg1/3Nb2/3)0.71Ti0.29]O3 (Sm-PMN-PT) ceramics possess excellent piezoelectric performance and exhibit great potential in electronic device applications. However, traditional fabrication methods commonly difficult to prepare Sm-PMN-PT ceramics with complex structures, which restricts their applications. Additive manufacturing techniques offer novel approaches to preparing Sm-PMN-PT ceramics. In the current investigation, Sm-PMN-PT ceramics with high-precision complex structures were successfully prepared by vat photopolymerization (VPP). In the first step, the Sm-PMN-PT ceramic slurry that can be employed for VPP technology is obtained by selecting photosensitive resins with high refractive index and optimizing the particle size of powders. The curing depth of slurry associated with the exposure time of 8s is obtained as 41 μm, the corresponding exposure power density is 37.5mW/cm2, and the viscosity pertinent to the shear rate of 100s-1 is obtained as 0.46Pa·s. The dimensional error of Sm-PMN-PT green bodies can be controlled within 270 μm, and the relative density of sintered Sm-PMN-PT ceramics reaches 98%. The results reveal that Sm-PMN-PT ceramics exhibit excellent dielectric and piezoelectric properties, where the relative dielectric constant εr, dielectric loss tanδ, and piezoelectric coefficient d33 in order are 6452, 0.0434, and 1230 pC/N. Additionally, Sm-PMN-PT ceramic components with triply periodic minimum surface (TPMS) structures are successfully employed to fabricate 3-3 piezocomposite, and d33 of piezocomposites could reach 432 pC/N, the output voltage could touch 80mV when subject to periodical forced vibration. The present research demonstrates that VPP technology is capable of successfully fabricating Sm-PMN-PT ceramics with high piezoelectric performance and high-precision complex structures, thereby broadening their application range.