Formation processes of some lead-containing niobate materials

The phase-formation sequence in the PbO-Nb2O5 system for compounds with the oxide relations of PbO:Nb2O5=1/2 to 6 has been studied by chemical phase-, quantitative-, thermographic (determination of thermal effects of reactions) and X-ray diffraction methods. Under isothermal and nonisothermal conditions the kinetic parameters of reactions, specified by diffusion transfer of lead- and oxygen ions, have been determined. Similar investigations have been carried out in the ternary systems of PbO-MgO-Nb2O5 and PbO-BaO-Nb2O5. The methods to obtain lead metaniobate using chemical coprecipitation have been developed