Effect of annealing conditions on the structure, phase and granulometry composition, and reflectance spectra and their changes on irradiation for calcium silicate powders

•High temperature annealing of calcium silicates.•Synthetic wollastonite produced from multicomponent system.•High-temperature phases of pseudo-wollastonite and silica.

High-temperature annealing of hydrated forms of calcium silicate produced in the multicomponent system CaCl2Na2SiO3H2O yields the formation of a heterophase structure containing high-temperature phases of pseudo-wollastonite and silica. Under these conditions, it is observed that there is an increase in the calcium silicate crystal lattice energy, particle size, reflection coefficient in the visible and near-IR spectral ranges, and radiation stability of the synthesized powders. The improved characters make the work useful, interesting and important.