Papers by Keyword: Nano-β-TCP

Abstract: In this study, a mental matrix composite (MMC) made of Mg-3Zn-0.8Zr alloy as a matrix and β-TCP particles as reinforcements were prepared for investigating the effect of β-TCP spherical particles sized in 100 nm on the microstructure of that alloy. The grains of as-cast or as-extruded Mg alloys systematically decreased from about 80 μm to about 30 μm with the choice of β-TCP contents. X-ray diffraction (XRD) analysis and optical microscopy (OM) observations show that the Mg-3Zn-0.8Zr-β-TCP (1.0 or 1.5, in wt %) composites were composed of various phases in addition to Mg and MgZn₂ comparied with Mg-Zn-Zr alloy. New diffraction peaks appearing in the MMC, which suggests that a potential interaction occurred between β-TCP and the matrix. Transmission electron microscopy (TEM) images reveal that secondary phases, which wraps upon the surface of β-TCP, are uniformly distributed in the grains of Mg-Zn-Zr alloy. Energy spectrum analysis shows that the component of dark-colored parts is equivalent to β-TCP, but the component of light-colored parts is Mg-Zn-Ca, which demonstrates that there is a real interaction occurred between the matrix and β-TCP.

Abstract: The biphasic calcium phosphate (BCP) concept was introduced to overcome disadvantages of single phase biomaterials. In this study, we prepared BCP from nanoHA and β-TCP that were synthesized via a solid state reaction. Three different ratios of pure BCP and collagen-based BCP scaffolds (%HA/%β-TCP; 30/70, 40/60 and 50/50) were produced using a polymeric sponge method. Physical and mechanical properties of all materials and scaffolds were investigated. XRD pattern proved the purity of each HA, β-TCP and BCP. SEM showed overall distribution of macropores (80-200 µm) with appropriate interconnected porosities. Total porosity of pure BCP (93% ± 2) was found to be higher than collagen-based BCP (85%± 3). It was observed that dimensional shrinkage of larger scaffold (39% ± 4) is lower than smaller one (42% ± 5) and scaffolds with higher HA (50%) ratio experienced greater shrinkage than those with higher β-TCP (70%) ratio (45% ±3 and 36% ±1 respectively). Mechanical properties of both groups tend to be very low and collagen coating had no influence on mechanical behavior. Further studies may improve the physical properties of these composite BCP.