Oriented Structure and Superconducting Properties in Dense Y₁Ba₂Cu₃ Oxides Prepared by Press Forging

Abstract

Dense Y1Ba2Cu3 oxides with a highly oriented structure were prepared by press forging at temperatures above 1248 K in air. The c plane of the oxides is preferentially oriented perpendicular to the pressing direction, and the orientation factor (F) and density attained by press forging at 1273 K are 0.58 and 6.19 Mg/m3, respectively. Subsequent annealing treatment for 36 h at 1173 K and for 200 h at 773 K in O2 for the press forged oxides causes a high-T c superconductivity with T c of 90 K and J c of 800 A/cm2 at 77 K in zero field. The J c value seems to be attributed to the highly oriented and densified structure.

Optical, luminescence, and scintillation properties of ZnO and ZnO:Ga ceramics

“…A technique proposed in Ref. 13 for calculating the texture factor was used to monitor the texture-i.e., the predominant orientation of the crystallographic planes in the ceramic samples. The texture factor was calculated from unambiguously indexed reflection lines from the ͑100͒, ͑002͒, ͑101͒, ͑102͒, ͑110͒, and ͑103͒ planes by comparing the intensities of these lines from the texturized test sample with standard data for this material, taken from the I.C.P.D.S.…”