Thermodynamics Research Center, ThermoML : Journal of Chemical Thermodynamics

Thermodynamic investigation on the Mg-Pd intermetallic phases

Delsante, S., Novakovic, R., Gagliolo, A., Borzone, G.
J. Chem. Thermodyn. 2019, 139, 105890
ABSTRACT
New thermodynamic information on Mg Pd alloys has been obtained in the Mg-rich part by using a hightemperature direct drop calorimeter and a high sensitive Differential Scanning Calorimeter (DSC). The calorimetric results have been validated by X-ray Powder Diffraction and Scanning Electron Microscopy coupled with Electron Probe Microanalysis analyses. The following values (kJ*mol-atom 1) of the enthalpy of formation at 27 C were obtained: -(28.2 +- 1) for Mg6Pd and -(39.5 +- 2.8) for Mg5Pd2 intermetallic phases. DSC has been employed to determine the transformation temperatures in the Mg-rich region: the congruent melting behaviour of the Mg6Pd and Mg5Pd2 phases was confirmed at a temperature of (568 +- 1) C and (691 +- 1) C, respectively and for the Lcents(Mg) + Mg6Pd eutectic reaction, a temperature of (530 +- 1) C was measured. In addition, a melting enthalpy of DfusH = (7.4 +- 0.1) kJ*mol-atom 1 and of (8.3 +- 0.1) kJ*mol-atom 1 for Mg6Pd and Mg5Pd2, respectively, was obtained.
Compounds
# Formula Name
1 Mg magnesium
2 Pd palladium
3 Mg5Pd2 palladium-magnesium compound (Mg5Pd2)
4 Mg6Pd palladium-magnesium compound (Mg6Pd)
Datasets
The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type Compound-# Property Variable Constraint Phase Method #Points
  • POMD
  • 3
  • Normal melting temperature, K ; Crystal
  • Crystal
  • Liquid
  • Air at 1 atmosphere
  • DTA
  • 1
  • POMD
  • 3
  • Molar enthalpy of transition or fusion, kJ/mol ; Crystal
  • Crystal
  • Liquid
  • Air at 1 atmosphere
  • DSC
  • 1
  • POMD
  • 4
  • Normal melting temperature, K ; Crystal
  • Crystal
  • Liquid
  • Air at 1 atmosphere
  • DTA
  • 1
  • POMD
  • 4
  • Molar enthalpy of transition or fusion, kJ/mol ; Crystal
  • Crystal
  • Liquid
  • Air at 1 atmosphere
  • DSC
  • 1
  • POMD
  • 1
  • 2
  • Eutectic temperature, K ; Crystal - 1
  • Crystal - 1
  • Crystal of intercomponent compound 1
  • Liquid
  • Air at 1 atmosphere
  • DTA
  • 1
  • RXND
  • 1
  • 2
  • 4
  • Molar enthalpy of reaction, kJ/mol
  • Solution calorimetry
  • 1
  • RXND
  • 1
  • 2
  • 3
  • Molar enthalpy of reaction, kJ/mol
  • Solution calorimetry
  • 1