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The structure of polycrystalline strontium barium niobate at room temperature was refined by the Rietveld method. Sintered ceramic samples were used to collect powder neutron and X-ray diffraction data. The ratio Sr/Ba ~ 64/36 was found from the initial batch composition Sr0.61Ba0.39Nb2O6, corroborating with the quantitative X-ray dispersive spectroscopy (EDS) measurements. The structure is tetragonal with cell parameters a, b = 12.4504(3) Å and c = 3.9325(1) Å and space group P4bm. It was not necessary to introduce any positional disorder for the oxygen atoms. Cation Nb+5 displacements not parallel to the c direction are presented, which can influence the behavior of the ferroelectric properties

Several conditions for hydroxyapatite ceramic preparation were used: sintering at 1150 °C in air or under H2O vapor flow, quenched in water at room temperature after sintering, or slow cooling inside the furnace. Depending on specific combinations of these preparation conditions, in the resulting ceramics significant differences are observed in the phase composition and dielectric properties, ranging from capacitive to a semiconducting response. Comparison between the experimental x-ray diffraction patterns and those calculated by the Rietveld method show that during sintering in air, approximately 40% of hydroxyapatite is transformed to tricalcium phosphate. The XRD analysis shows that this transformation could be possible using the following process: Ca10(PO4)6(OH)2 = 2Ca3(PO4)2 + Ca2P2O7 + 2CaO + H2O.

Ceramic materials were produced at different temperatures, and the gases released during firing were analyzed using a commercial system based on photothermal techniques. Emissions of CO, CO2, NO, N2O, and CH4 were observed, while NH3 and SO2 were not observed within our detection limits (1 ppm). The evolution of crystalline phases, open porosity, volumetric shrinkage, and rupture tension were correlated to the amount of gases released at different temperatures, ranging from 300 to 1200 °C, and these results can be applied to an optimization of the production process.