TY - JOUR
T1 - Interactions of Ba2YCu3O6+y with the Gd3NbO7 buffer layer in coated conductors
AU - Wong-Ng, W.
AU - Yang, Z.
AU - Kaduk, J. A.
AU - Cook, L. P.
AU - Paranthaman, M.
PY - 2010/3
Y1 - 2010/3
N2 - A systematic study of the chemical interaction of Ba2YCu3O6+y and Gd3NbO7 was conducted under two processing conditions: purified air (21% po2), and 100 Pa po2 (0.1% po2). Phases present along the pseudo-binary join Ba2YCu3O6z and Gd3NbO7 were found to be in two five-phase volumes within the BaO - frac(1, 2) Y2 O3 - frac(1, 2) Gd2 O3 - Nb2 O5 - CuOy system. Three common phases that are present in all samples are (Y,Gd)2Cu2O5, Ba(Y,Gd)2CuO5 and Cu2O or CuO (depending on the processing conditions). The assemblies of phases can be categorized in three regions, with Ba2YCu3O6+y: Gd3NbO7 ratios of (I)<5.5:4.5; (II)=5.5:4.5; and (III)>5.5:4.5. The lowest melting temperature of the system was determined to be ≈938 °C in air, and 850 °C at 100 Pa po2. Structure determinations of two selected phases, Ba2(GdxY1-x)NbO6 (Fm3-m, No. 225), and (GdxY3-x)NbO7 (C2221, No. 20 and Ccmm, No. 63), were completed using the X-ray Rietveld refinement technique. Reference X-ray powder diffraction patterns for selected phases of Ba2(GdxY1-x)NbO6 (x=0.2, 0.4, 0.6, and 0.8) and (GdxY3-x)NbO7 (x=0.6, 1.2, 1.8, 2.4 and 3) have been prepared for inclusion in the Powder Diffraction File (PDF).
AB - A systematic study of the chemical interaction of Ba2YCu3O6+y and Gd3NbO7 was conducted under two processing conditions: purified air (21% po2), and 100 Pa po2 (0.1% po2). Phases present along the pseudo-binary join Ba2YCu3O6z and Gd3NbO7 were found to be in two five-phase volumes within the BaO - frac(1, 2) Y2 O3 - frac(1, 2) Gd2 O3 - Nb2 O5 - CuOy system. Three common phases that are present in all samples are (Y,Gd)2Cu2O5, Ba(Y,Gd)2CuO5 and Cu2O or CuO (depending on the processing conditions). The assemblies of phases can be categorized in three regions, with Ba2YCu3O6+y: Gd3NbO7 ratios of (I)<5.5:4.5; (II)=5.5:4.5; and (III)>5.5:4.5. The lowest melting temperature of the system was determined to be ≈938 °C in air, and 850 °C at 100 Pa po2. Structure determinations of two selected phases, Ba2(GdxY1-x)NbO6 (Fm3-m, No. 225), and (GdxY3-x)NbO7 (C2221, No. 20 and Ccmm, No. 63), were completed using the X-ray Rietveld refinement technique. Reference X-ray powder diffraction patterns for selected phases of Ba2(GdxY1-x)NbO6 (x=0.2, 0.4, 0.6, and 0.8) and (GdxY3-x)NbO7 (x=0.6, 1.2, 1.8, 2.4 and 3) have been prepared for inclusion in the Powder Diffraction File (PDF).
KW - BaYCuO and GdNbO interactions
KW - Reference X-ray powder patterns
KW - Structure of Ba2(GY)NbO and (GdY)NbO
KW - Superconductors
UR - http://www.scopus.com/inward/record.url?scp=77649185951&partnerID=8YFLogxK
U2 - 10.1016/j.jssc.2010.01.006
DO - 10.1016/j.jssc.2010.01.006
M3 - Article
AN - SCOPUS:77649185951
SN - 0022-4596
VL - 183
SP - 649
EP - 657
JO - Journal of Solid State Chemistry
JF - Journal of Solid State Chemistry
IS - 3
ER -