Temperature dependence of heat capacity of Fe–M powder nanomaterials (M—C, Ge, Sn)

Abstract

The heat capacity of mechanically activated nanocrystalline carbonyl iron and the sample of iron nanocomposite with the addition of isoelectronic sp-elements (C, Ge, Sn) with a grain size of the order of 2‒5 nm is determined in a temperature range of 300–450 K using an IT-s-400 calorimetric device. Thermalphysical studies of the temperature dependence of the heat capacity are performed for mixtures of nanocomposites differing by the composition 68 at % Fe–32 at % M (M—Ge, Sn) and 95 at % Fe–5 at % C. It is shown that the introduction of sp-elements into nanocrystalline iron leads to substantial variations in the heat capacity over the whole temperature range under study. The heat capacity strongly depends on the introduced sp-element and degree of disorder of the formed material.