High-temperature in situ observation of Nd–Sm–Ba–Cu–O system by laser-scanning microscopy

Abstract We have studied the quasi-binary phase diagrams of RE–Ba–Cu–O systems, in which rare earth (RE) site is composed of Nd, Sm and its mixture, along the line connecting RE123 and Ba 3 Cu 5 O y (035) in 1% O 2 and 21% O 2 in Ar. The nucleation and melting of REBa 2 Cu 3 O y and RE 2 BaCuO 5 /RE 4 Ba 2 Cu 2 O 10 were observed in situ and the liquidus lines were determined using a laser-scanning microscope. Phase identification was performed on the samples quenched from high temperatures through X-ray powder diffraction measurements and electron probe microanalysis.