EFFECT OF POTASSIUM ON THE HEAT CAPACITY AND THERMUNCTIONS OF AlFe5K10 ALUMINIUM ALLOY

Abstract

Heat capacity is the most important characteristic of substances, and its change with temperature can determine the type of phase transformation, Debye temperature, the energy of formation of vacancies, the electron heat capacity coefficient, and other properties. In the work, the heat capacity of the AlFe5K10 alloy with potassium was determined in the “cooling” mode from the known heat capacity of the standard copper sample. In order to succeed, by processing the curves of the cooling rates of the samples of the aluminum alloy AlFe5K10 with potassium and the standard, polynomials describing their cooling rates were obtained. Further, according to the experimentally found values of the cooling rates of the samples of alloys and the standard, knowing their masses, the polynomials of the temperature dependence of the heat capacity of the alloys and the standard were established, which are described by a four-termed equation. Using integrals of specific heat, models of the temperature dependence of the change in enthalpy, entropy and Gibbs energy were established. The dependences obtained show that with increasing temperature, the heat capacity, enthalpy and entropy of the alloys increase, while the values of Gibbs energy decrease. At the same time, potassium addition reduces the heat capacity, enthalpy and entropy of the original AlFe5K10 aluminium alloy. The value of Gibbs energy increases in that case.