STUDY OF THE EFFECT OF THERMAL CYCLING AND HEATING RATE ON THE BEHAVIOR OF METALLIC BERYLLIUM IN A VAPOR-ARGON ENVIRONMENT BY THE TGA METHOD

This study investigates the behaviour of metallic beryllium under high-temperature corrosion in a water-steam-argon atmosphere under thermal cycling conditions using thermogravimetric and differential scanning calorimetric analysis (TGA/DSC). The experiments were conducted at three heating rates (10, 20, and 30 K/min), each including two thermal cycles (C1 and C2). Oxidation was evaluated by mass gain and thermal effects, and kinetic parameters (Ea, K0) were determined from logarithmic Arrhenius dependencies with normalisation to surface area and partial water vapour pressure. Two characteristic temperature ranges were established: initial thermal activation (775–1050 K) and high temperature (975–1170 K), as well as a transition zone between them. For the high-temperature region, the activation energy Ea = 146 kJ/mol and the pre-exponential factor K0 = 2.41·10⁻¹ mg/(s·cm²·Pa) were obtained. The results obtained deepen the understanding of the mechanisms of beryllium oxidation during thermal cycling and can be used to assess safety in nuclear fusion installations.

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