Investigation of thermal expansion and specific heat of cesium loaded iron phosphate glasses

High temperature thermal expansion and specific heat measurements were carried out on iron phosphate glass (IPG) and a series of cesium substituted iron phosphate glasses. Thermal expansion of the bare IPG and the effect of cesium loading on expansion behavior were determined by push rod dilatometry in the temperature range of 300–700 K in air. Specific heat was also measured in the same temperature range by differential scanning calorimetry (DSC) under flowing argon atmosphere. Enthalpy increment was computed using the specific heat data. The enthalpy increments were also measured using isoperibol drop calorimetry in air in the same temperature range. Specific heat was evaluated from the experimental enthalpy increment data. The experimentally measured enthalpy increment data were compared with those evaluated from DSC data for iron phosphate and cesium loaded iron phosphate glasses.