Abstract

The kinetics of devitrification of samples with compositions of the akermanite-gehlenite system (Ca 2Al 2−2yMg ySi 1+yO 7 (0 ≦ y ≦ 1) doped with 2% Nd have been studied. It was shown that emission spectra of neodymium in partially devitrified samples can be expressed as superposition of the spectra for glass and crystalline phases of the same chemical composition. This superposition permits the determination of the degree of devitrification. The kinetics of devitrification for those samples were described by the simplest Avrami equation: α = 1 − exp(− kt) (α is the degree of devitrification, k is a rate constant). The activation energy of devitrification process corresponds to that found in molten silicates (≈ 700 kJ/mol).

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call