Domain structure and Y2BaCuO5distribution in single- and multiple-domain melt-textured YBaCuO

✍ Scribed by Pavel Diko; Volker R. Todt; Dean J. Miller; Kenneth C. Goretta

• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 1019 KB
• Volume: 21
• Category: Article
• ISSN: 0749-6036
• DOI: 10.1006/spmi.1996.0409

✦ Synopsis

Microstructural features such as subgrains, Y 2 BaCuO 5 particles, and high-angle boundaries were studied in single-and multiple-domain melt-textured YBaCuO levitators. Subgrains elongated in the c-or a-direction and rectangular in cross section were formed during solidification by cellular growth. Formation of subgrains by combination of a-and c-growth was also observed. Their boundaries were predominantly low angle, and were not cracked or wetted by second phases. Macrosegregation of Y 2 BaCuO 5 particles developed mainly in the regions formed by c-axis growth. The segregation is related to a Y 2 BaCuO 5 particle pushing by the YBa 2 Cu 3 O 7-x growth front, in combination with coarsening by Ostwald ripening and agglomeration. The structure of 90 • high-angle grain boundaries appeared to be similar to that of the low-angle grain boundaries.