Addressing critical-size bone defects in load-bearing areas remains a significant challenge in orthopedic surgery. Ti6Al4V scaffolds are commonly employed due to their superior biomechanical stability, though their lack of electrical activity limits their further use. To overcome this, we fabricated Ti6Al4V-barium titanate bulk composite scaffolds, combining the mechanical stability of Ti6Al4V with the electrical activity of biocompatible piezoelectric barium titanate. Electron beam melting was used to manufacture a hollow cylindrical Ti6Al4V structure, which was subsequently combined with barium titanate powder and processed via field-assisted sintering technology. Scanning electron microscopy confirmed that the Ti6Al4V lattice structure integrated well with the barium titanate matrix without significant deformation. The resultant scaffolds exhibited an average piezoelectric constant of 4.92±0.75 pC/N. This value is very close to the values of natural bone. Additionally, nanoindentation tests showed that the Ti6Al4V is the harder and stiffer part of the composite scaffold.

Additionally, we combined barium titanate with 45S5 bioactive glass to develop composites that are not only piezoelectric but also potentially bioactive. Our goal was to create dense piezoelectric samples while maintaining low crystallization of the bioactive glass to maximize bioactivity. The samples were produced using varying material compositions and field-assisted sintering temperatures. These samples were successfully polarized, with piezoelectric constants varying from 0.8 to 3.4 pC/N depending on the bioactive glass content, making them comparable to natural bone tissues. Overall, we have established a process window for field-assisted sintering that enables the fabrication of piezoelectric and potentially bioactive biomaterials for tissue engineering applications.

We are currently focused on producing interconnected porous lithium sodium potassium niobate piezoelectric ceramics, utilizing zinc-oxide tetrapods as space holders in the field-assisted sintering process, with the aim for more effective bone defect treatments.