Temperature Dependence of Heat Capacity of Fe-M Powder Nanomaterials (M-C, Ge, Sn)

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. Thermal-physical 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.