
Особенности полиморфного превращения при нагреве и охлаждении кобальта
Author(s) -
Л.В. Спивак,
Н.Е. Щепина
Publication year - 2022
Publication title -
žurnal tehničeskoj fiziki
Language(s) - English
Resource type - Journals
eISSN - 1726-748X
pISSN - 0044-4642
DOI - 10.21883/jtf.2022.04.52244.295-21
Subject(s) - recrystallization (geology) , differential scanning calorimetry , enthalpy , thermodynamics , cobalt , materials science , activation energy , crystallite , metal , chemistry , metallurgy , physics , paleontology , biology
Differential scanning calorimetry was used to study the regularities of polymorphic αβ transformation in polycrystalline cobalt. The value of the activation energy of the αβ transformation during heating of cobalt (29050 kJ/mol), enthalpy and entropy, depending on the thermal history of the metal, is determined. It is shown that the mechanisms of recrystallization under heating are closer to the first-order I phase transformations. When cooling under conditions of limited diffusion mobility of cobalt atoms, recrystallization is apparently carried out due to the passage of several diffusion-free mechanisms of phase transformation, implemented in close temperature ranges.