Oxidation of Zirconium Alloyed with Chromium Atoms by Means of Impact of Compression Plasma Flows

Abstract

The results of studies on the zirconium crystal structure after initial stages of oxidation in an open air at temperature of 700°C for 15 min are presented. Samples of commercial pure zirconium with a minimal content of impurity atoms as well as chromium-alloyed zirconium have been studied by means of the action of compression plasma flows. The possibility of alloying the zirconium near-surface layer with chromium, with a chromium coating thickness of 1 μm, by means of compression plasma flows with the absorbed energy density of 25–43 J/cm2 has been demonstrated. Stabilization of the high-temperature zirconium β phase in the form of β-Zr(Cr) solid solution and intermediate martensite α'-Zr phase has been observed. After isothermal annealing of zirconium samples at T = 700°C and irradiated with plasma flow with Qmax = 43 J/cm2, no effect of the surface layer alloying with chromium atoms has been observed owing to its intense evaporation and ablation in the course of surface heating by plasma flow, as well as increased resistance to high-temperature oxidation at the initial stages in comparison with the initial state.