Microstructure, mechanical properties and in vitro bioactivity of akermanite scaffolds fabricated by laser sintering

Akermanite had attracted great attention due to the favourable mechanical properties and excellent biological performance. In this research, the microstructure and mechanical properties of akermanite scaffolds fabricated via laser sintering under different process conditions were studied and characterized. The results showed that the akermanite particles gradually mixed together, grew up and reached complete densification with the scanning speed decreasing from 450 to 150 mm/min, while micro defects such as air holes occurred at 50mm/min. simultaneously, the compressive strength of the scaffolds went up and then descended, and the optimum value was 5.92 ± 0.41 MPa. The Vickers hardness and fracture toughness increased consistently and then tended to stabilize. X-ray diffraction (XRD) results indicated no new phase appeared under all process conditions. MG-63 cell culture revealed that cell adhesion and proliferation occurred, indicating excellent cytocompatibility of the scaffolds. Moreover, in vitro bioactivity tests showed that the apatite layer formed on the scaffolds and became dense and thick with the increase of soaking time in simulated body fluid (SBF), and this fact was further confirmed by energy-dispersive spectroscopy (EDS).