Preparation and characterization of HA–BT composite bioceramics by DLP 3D printing

As clinical demand for enhanced osseous repair implants continues to increase, ceramic-based composites have attracted widespread attention owing to their superior mechanical properties and excellent biocompatibility. Hydroxyapatite (HA), although an ideal biocompatible matrix material, is limited by insufficient mechanical strength and the absence of piezoelectric activity, restricting its application in load-bearing bone repair. To address these limitations, digital light processing (DLP) 3D printing technology was used in this study to fabricate piezoelectrically active hydroxyapatite–barium titanate (HA–BT) nanocomposite scaffolds. A systematic investigation was conducted to examine the phase composition, microstructure, mechanical performance, piezoelectric properties, dielectric behavior, corrosion resistance, and biocompatibility of HA–BT specimens with varying ratios. The results demonstrated that, compared to pure HA, the 60 wt% BT composite scaffold exhibited significantly enhanced properties, including a compressive strength of 106.67 MPa (a 194 % increase over that of pure HA), a density of 91.43 %, a piezoelectric constant d 33 of 6.34 pC/N, a dielectric constant ε r of 93.6, and a corrosion current density of 7.1779 × 10 −5 A/cm 2 . In addition, the scaffold exhibited favorable cellular proliferation. The key performance metrics of this composite closely matched those of human bone, providing valuable insights into the design and fabrication of high-precision, high-performance artificial bone-repair constructs.