Influence of sintering temperature on structure and strength of β-tricalcium phosphate bioceramic obtained by freeze drying process
Year: 2026
Type: conference-paper
Abstract: The aim of present paper is to investigate the influence of sintering temperature on structure and strength properties of β-tricalcium phosphate (β-TCP) bioceramic obtained by freeze drying process. Cylindrical β-TCP samples were prepared by freeze drying process and subjected to sintering at 1100, 1200 and 1300 °C. The porosity, microstructure and phase composition were investigated by optical microscopy, SEM, XRD, FTIR and pore analyzer. The maximum breaking force was measured through compression test and compression strength was calculated. It was found that the phase composition of the samples after sintering at different temperatures is monophasic consisting of β-TCP. The freeze dried β-TCP samples were characterized with inhomogeneous porous macrostructure and several cracks in the volume. The macrostructure after sintering was more homogeneous with preserved cracks in the volume and several new cracks formed near the boundary between the porous top region and the denser internal structure. The microstructure of sintered samples was porous, consisting of conglomerates of various shapes and interconnected pores (5-50 μm) with irregular shape. Larger grains are observed at higher temperature of 1300 °C. Increasing the temperature led to shrinkage increase and linear decrease of porosity from 72% at 1100 °C to 55% at 1300 °C. Inverse proportional relationship was confirmed between the porosity and breaking force in compression. The maximum load increased from 13 N up to 727 N with temperature increase from 1100 °C to 1300 °C. A similar trend was observed in compressive strength: it increased with temperature increase from 0.06 MPa at 1100 °C, 0.62 MPa at 1200 °C and the highest 6.43 MPa at 1300 °C.
Institutions: Medical University of Varna, Technical University of Gabrovo
Subfield: Biomedical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W7214584963