1. Dept. of High Temperature Strength of Structural Materials in Gas and Liquid Metal Media, Karpenko Physico-Mechanical Inst. of National Academy of Sciences of Ukraine, 5 Naukova Str., L’viv, 79060, Ukraine (Corresponding author), e-mail: fedirko@ipm.lviv.ua
2. Dept. of High Temperature Strength of Structural Materials in Gas and Liquid Metal Media, Karpenko Physico-Mechanical Inst. of National Academy of Sciences of Ukraine, 5 Naukova Str., L’viv, 79060, Ukraine