INFLUENCE OF ZINC ON THE THERMOPHYSICAL PROPERTIES AND THERMODYNAMIC FUNCTIONS OF LEAD BABBITT B(PbSb15Sn10)

Lead-based babbitt, which has high thermal conductivity and excellent compliance with requirements, is com- monly used by manufacturers in applications for systems that will be subjected to impact loads. Some lead-based babbitt products have a uniform grain structure, so they can be used for heavy loads at low constant speeds. In addition, lead-based babbitt is an economical alloy, therefore it can be used for general-purpose machinery, line shafts, and machine shops. It can also be used in agricultural machinery, cement equipment, conveyors, elevators, and metallurgical equipment. The thermodynamic and thermophysical properties of lead and its alloys are the subject of numerous ex- perimental and theoretical studies. Available experimental data include measurements of heat capacity, enthalpy, entropy, and Gibbs energy at normal pressure in the temperature range 298.15–550 K. The paper presents the results of experimental determination of the heat capacity of lead babbitt B(PbSb15Sn10), alloyed with zinc, and calculation of the temperature dependence of changes in the thermodynamic functions of this al- loy. The studies of the temperature dependence of the heat capacity of lead babbitt B(PbSb15Sn10), alloyed with zinc, were carried out in the "cooling" mode using computer technology and the Sigma Plot 10.0 program. Polynomials of the temperature dependence of the heat capacity and changes in the thermodynamic functions (enthalpy, entropy, and Gibbs energy) of lead babbitt B(PbSb15Sn10), alloyed with zinc, and the standard (Pb grade C00) were established, which with the correlation coefficient Rcor = 0.999 describe these changes. It is shown that with an increase in the zinc content, the heat capacity of the original alloy increases. The enthalpy and entropy of lead babbitt B(PbSb15Sn10), alloyed with zinc, increase with the temperature and zinc content, and the value of the Gibbs energy decreases.

Author:  I. N. Ganiev, M. B. Jumaeva, Kh. M. Khojanazarov, H. O. Odinazoda, and S. U. Khudoyberdizoda
Keywords:  lead babbitt B(PbSb15Sn10), zinc, "cooling" mode, temperature dependence, heat capacity, heat emission coefficient, enthalpy, entropy, Gibbs energy
Page:  757