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The aim of this work was synthesis and characterization of amorphous and crystallized 58S nanopowders produced via sol‐gel method. According to the thermal analysis, the nanopowders were heat‐treated at 600°C and 1100°C. X‐ray diffraction results revealed that the phases of Wollastonite and tricalcium phosphate were formed at 1100°C. The in vitro tests showed that hydroxyl carbonate apatite was precipitated on both crystallized and amorphous nanopowders, while amorphous nanopowder showed a higher bioactivity than that of crystallized nanopowder. In contrast, mechanical properties of crystallized specimen were higher than those of amorphous specimen.

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In the present study, Co-Cr-Mo/58S bioglass porous nano-composite samples were successfully produced using 30 wt% carbonate hydrogen ammonium and polyvinyl alcohol solution as space holder and binder, respectively. The cold compacted samples were heated at 175°C for 2 h and then were heated to sinter at 1100, 1150, 1200 and 1250°C for 3, 6, 9 and 12 h. True porosity of samples was measured and the samples were characterized using the X-ray diffraction (XRD) technique, scanning electron microscopy (SEM) and compressive test. Although the results of compression test for samples sintered at 1200 and 1250°C showed that the shape of stress-strain curves were similar to each other, compacted powders sintered at 1100 and 1150°C exhibited some fluctuations. Moreover, the compressive strength increased by decreasing the true porosity, indicating the role of high temperature on the sintering process. In addition, volume diffusion was predominant mechanism for these samples at sintering temperature of 1250°C. SEM images of the porous sample sintered at 1250°C for 3 h showed an appropriate range of pore sizes and interconnectivity. The XRD results showed that there are no contaminations and new phase is detectable in the sintered porous samples.

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