Manufacture and characterization of a new Si-Ca-P biphasic ceramic

A ceramic of eutectoid composition based on a silicocarnotite (S)- tricalcium phosphate (TCP) sub-system was prepared, and the morphology of the structure investigated. The ceramic material, obtained by a solid-state reaction and slow solidification (6 °C/min) through the eutectoid temperature region (1158 ± 2 °C), presented a typical eutectoid microstructure of alternate layers of both silicocarnotite and α-TCPss phases. The microstructure of the two phases was homogeneous and free of crystalline and structural defects. High-resolution electron microscopy revealed that the interfaces between the α-TCPss and silicocarnotite lamellae within the eutectoid grains were faultless and no sign of an intermediate region between both phases. Moreover in both phases, the lattice planes resolved at the interface were free of defects. The orientation relation between the lamellae of the eutectoid grains was determined as follows: {130} α-TCPss // {302} silicocarnotite. This eutectoid lamellae structure presents a new approach for the bioengineering application for hard tissue replacement as the material combines unique structural and bioactive properties and provides a platform for direct integrations with natural tissue.