Accession Number : AD0662653

Title :   THE SPECIFIC HEAT OF TIN AND GALLIUM IN THEIR STABLE AND UNDERCOOLED PURE LIQUID STATES.

Descriptive Note : Technical rept.,

Corporate Author : HARVARD UNIV CAMBRIDGE MASS DIV OF ENGINEERING AND APPLIED PHYSICS

Personal Author(s) : Chen,H. S. ; Turnbull,D.

Report Date : NOV 1967

Pagination or Media Count : 16

Abstract : The specific heats, C sub p, of tin and gallium in their pure liquid state over the temperature range from 632 for tin and 611 gallium to 425 and 245K, corresponding to undercoolings of 80 and 58K respectively have been measured. Over the entire temperature range, the C sub p for both tin and gallium falls continuously with increasing temperature through their melting point with no singular behavior there. The excess specific heat, delta C sub p, of the liquid over the corresponding crystal diverges with falling temperature from -0.38 for tin and 0.56 for gallium at their melting point to +0.27 and 1.04 cal/g-atm-K at the lowest temperature to which the particular specimen could be undercooled. For both tin and gallium, the specific heat at constant volume, C sub v, of the liquid at their melting point exceeds the Dulong Petit limit value of 3R, and rises with decreasing temperature. The excess specific heat, delta C sub p, as well as delta C sub v, of liquid over the corresponding crystal in the undercooled region is attributed to the taking up of configurational entropy with rising temperature. (Author)

Descriptors :   (*TIN, SPECIFIC HEAT), (*GALLIUM, SPECIFIC HEAT), LIQUID METALS, SUPERCOOLING

Subject Categories : Metallurgy and Metallography
      Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE