A study of thermal parameters of Ag50Pd50 alloy using X-ray diffraction

Thermal parameters of Ag₅₀Pd₅₀ alloy were studied using the in-situ X-ray diffraction (XRD) technique. Diffraction experiments in the temperature range 308-1178 K showed that the alloy forms a face centered cubic (fcc; A1-type) structure. Temperature dependence of the lattice parameter was investigated using the Bragg line displacement method. Results show that the lattice parameter for the alloy increases with increase in temperature. The temperature dependent XRD data was utilized to determine the mean linear thermal expansion (MLTE (%)) and coefficient of thermal expansion (CTE) ‘α’ in the mentioned temperature range. It was observed that the values of CTE vary between 9.3 and 14.6 K⁻¹]10⁻⁶]. The same data was also utilized to determine the Debye temperatures Θ_D and mean square amplitude of vibration (MSAV) (u²(T)) for this alloy. Values of thermal parameters as determined in this investigation are in good agreement with the estimated values as well as with those for other alloys of noble metals.