Effects of Eu2O3 on liquid–liquid phase separation of PbO–B2O3, BaO–B2O3 and SrO–B2O3 glasses

Abstract The effects of Eu 2 O 3 on liquid–liquid phase separation were studied in the RO–B 2 O 3 –Eu 2 O 3 (R represents Pb, Ba or Sr) systems. The results from the in situ observation of the phase separation showed that, in every case, Eu 2 O 3 addition increased the immiscibility temperatures and the effect was more pronounced as the RO content decreased. The Eu distribution in the phase-separated microstructure was examined with an electron probe microanalyser (EPMA) and a field emission scanning electron microscope (FE-SEM) with an energy dispersive X-ray spectrometer (EDS). It was found that the Eu dissolved preferentially in the RO-rich phase droplets with a uniform distribution. A comprehensive account for these effects of Eu 2 O 3 on both the immiscibility temperature and the microstructure was given by considering the RO–B 2 O 3 –Eu 2 O 3 ternary phase diagram. For the SrO–B 2 O 3 –Eu 2 O 3 system, the Eu 2 O 3 concentration in the droplets was measured with EDS analysis to be found adjustable by changing batch composition.