Title :
Annealing and mechanical properties of bulk Y-Ba-Cu-O
Author :
Goretta, K.C. ; Diko, P. ; Ming Jiang ; Cuber, M.M. ; Ming Xu ; Ostenson, J.E. ; Sengupta, S.
Author_Institution :
Argonne Nat. Lab., IL, USA
fDate :
6/1/1999 12:00:00 AM
Abstract :
Melt-processed YBa/sub 2/Cu/sub 3/O/sub x//Y/sub 2/BaCuO/sub 5/ and conventional polycrystalline sintered YBa/sub 2/Cu/sub 3/O/sub x/ pellets were prepared. Elastic modulus, hardness, and fracture strength were measured on selected sections cut from the pellets. Strength in the melt-processed pellets ranged from 32 to 94 MPa and was highest in the center. Variations in strength were related to microstructural features, especially Y/sub 2/BaCuO/sub 5/ distribution. To improve strength, we attempted to minimize microcracking by manipulating cooling rates and annealing times. We found that control of annealing reduced microcracking of the polycrystalline sintered pellets, but had little effect on the single-domain melt-processed pellets.
Keywords :
annealing; barium compounds; elastic moduli; fracture toughness; hardness; high-temperature superconductors; microcracks; yttrium compounds; Y/sub 2/BaCuO/sub 5/ distribution; YBa/sub 2/Cu/sub 3/O-Y/sub 2/BaCuO/sub 5/; annealing time; cooling rates; elastic modulus; fracture strength; hardness; melt-processed pellets; microcracking; polycrystalline sintered pellets; Annealing; Cooling; Laboratories; Magnetic field measurement; Mechanical factors; Mechanical variables measurement; Microstructure; Superconductivity; US Department of Energy; Yttrium barium copper oxide;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
