Papers by Keyword: Amorphous State

Abstract: Thermophysical parameters of Finemet-type initially amorphous alloy produced using rapid quenching technique were determined. The temperature intervals of phase and structure changes have been obtained using calorimetry and non-ambient X-ray diffraction methods. The electric resistance data were recalculated to alloy electrical conductivity which it was recalculated to heat conductivity using the Wiedemann–Franz law. Resulting parameters were used for heat processes simulation that occurs in amorphous material of built-up transformer core during annealing in nanocrystallization temperature interval. Heat treatment of different sizes twisted magnetic cores was optimized.

Abstract: The amorphous state of poly (Narylenebenzimidazole ketone)(PNABIK) were determined using the Amorphous Cell Module of the Materials Studio program. The solubility improvement of PNABIK compared with traditional ploybenzimidazole (PBI) was also simulated by cohesive energy density (CED) calculating. PNABIK was synthesized by N-C coupling reaction to validate the rationality of simulation results and all the simulation results were consistent with the experimental tests.

Abstract: Methods of X-ray diffraction, transmission and scanning electron microscopy, and electron diffraction have been used to study phase and chemical compositions and structure of Ti₂NiCu alloys. The alloys of the quasi-binary section TiNi–TiCu, which exhibit in the initial as-cast state thermoelastic martensitic transformations B2↔B19 and related shape memory effects, have been produced by rapid quenching of the melt (melt spinning technique). The chemical composition of the Ti₂NiCu alloys was varied with respect to titanium and nickel within x ≤ ±1 at. %. The mechanical properties of the alloys have been measured in the initial state and after subsequent heat treatment. The kinetics of the crystallization from the amorphous state, devitrification processes and the forward and reverse thermoelastic martensitic transformations were investigated. Their characteristic temperatures have been determined by measuring temperature dependences of the electrical resistivity of the alloys. The diagram of the dependence of the critical temperatures on the chemical composition has been constructed.