A new ceramic sintering approach employing plastic deformation as the dominant mechanism is proposed, at low temperature close to the onset point of grain growth and under high pressure. Based on this route, fully dense boron carbide without grain growth can be prepared at 1,675–1,700 °C and under pressure of (≥) 80 MPa in 5 minutes. The dense boron carbide shows excellent mechanical properties, including Vickers hardness of 37.8 GPa, flexural strength of 445.3 MPa and fracture toughness of 4.7 MPa•m0.5. Such a process should also facilitate the cost-effective preparation of other advanced ceramics for practical applications.

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Fluoridated composite Hydroxyapatite biomaterial was prepared by sintering the hydroxyapatite Ca10 (PO4)6. (OH)2[HA] powder with addition of titanium fluoride 30 wt. % -TiF3 and mixture of iron oxide and aluminum oxide [5 wt. %-Al2O3/Fe2O3 ; (5/1)]. The pellets were prepared by conventional sol-gel technique. The as-prepared samples were sintered at various temperatures and the effect of different temperature on grain size and mechanical properties has been investigated. The samples were sintered at various temperatures of 1100-1400 °C. After sintering, the sample’s mechanical properties such as compressive strength, bending strength, Vickers hardness were improved to be 49±0.26-103±0.26 MPa, 19.6±0.20-36.2±0.20 MPa, and 7.97±0.16-12.50±0.16 GPa with their grains size 4.76±0.10-17.63±0.10 μm and bulk densities 1.8944-2.2426 g/cm3.