Phase equilibria in the oxide system Nd2O3-K2O-P2O5

作者：Szczygiel Irena^*; Znamierowska Teresa; Mizer Dagmara

来源：Solid State Sciences, 2010, 12(7): 1205-1210.

DOI：10.1016/j.solidstatesciences.2010.03.011

• Phase diagram
• Potassium-neodymium phosphates
• Oxide system
• DTA/DSC/TG
• X-ray powder diffraction

A phase equilibria diagram of the partial system NdPO4-K3PO4-KPO3 has been developed as part of the research aimed at determining the phase equilibrium relationships in the oxide system Nd2O3-K2O-P2O5. The investigations were conducted using thermoanalytical techniques, X-ray powder diffraction analysis and reflected-light microscopy. Three isopleths existing between: K3Nd(PO4)(2)-K4P2O7, NdPO4-K5P3O10 and NdPO4-K4P2O7 have been identified in the partial NdPO4-K3PO4-KPO3 system. Previously unknown potassium-neodymium phosphate "K4Nd2P4O15" has been discovered in the latter isopleth section. This phosphate exists in the solid phase up to a temperature of 890 degrees C at which it decomposes into the parent phosphates NdPO4 and K4P2O7. Four invariant points: two quasi-ternary eutectics, E-1 (1057 degrees C) and E-2 (580 degrees C) and two quasi-ternary peritectics, P-1 (1078 degrees C) and P-2 (610 degrees C), occur in the NdPO4-K3PO4-KPO3 region.

• 出版日期2010-7