Mechanical properties and bioactivity of β-Ca2SiO4 ceramics synthesized by spark plasma sintering

Bioactive beta-dicalcium silicate ceramics (β-Ca2SiO4) were fabricated by spark plasma sintering (SPS). The relative density of as-prepared β-Ca2SiO4 ceramics reached 98.1% when sintered at 1150 °C, leading to great improvement in bending strength (293 MPa), almost 10 times higher than that of the specimen prepared by conventional pressureless sintering (PLS). High fracture toughness (3.0 MPa m1/2) and Vickers hardness (5.8 GPa) of β-Ca2SiO4 ceramics were also achieved by SPS at 1150 °C. The simulated body fluid (SBF) results showed that β-Ca2SiO4 ceramics had a good in vitro bioactivity to induce hydraxyapatite (HAp) formation on their surface, which suggests that β-Ca2SiO4 ceramics are promising candidates for load-bearing bone implant materials.