Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5459642 | Journal of Alloys and Compounds | 2017 | 8 Pages |
Abstract
A series of MgB2 samples doped with C, RE2O3 oxides (REÂ =Â Ce, Nd), and C and RE2O3oxides was prepared by the hot isostatic pressing method at high pressure: 1Â GPa under argon gas. Based on X-ray diffraction and magnetization measurements it was found that the RE2O3 is not incorporated into MgB2. A secondary REB4 phase is present after the synthesis. No decrease in the critical temperature (Tc) is observed after the RE2O3 doping. The Tc of C and RE2O3 doped MgB2 is decreased by 3Â K. The doping decreases the diamagnetic response in comparison to pure MgB2 phase. The highest critical current density (Jc) was 3.4Â ÃÂ 105 A/cm2 at 4.2Â K and 0.5Â T for the bulk material, and the irreversibility field for the Nd2O3 doped sample was located at high field at TÂ =Â 30Â K. The results indicate that inside grains of pinning centers increase Jc from 4.2Â K to 25Â K and decrease Jc at 30Â K. On the other hand, pinning centers between grains (precipitate) increase Jc at 30Â K and decrease Jc from 4.2Â K to 25Â K in the middle and high magnetic fields. Our research shows that carbon-encapsulated boron creates a point pinning centers.
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
G. Gajda, A. Morawski, R. Diduszko, T. Cetner, M.S.A. Hossain, K. Gruszka, D. Gajda, P. Przyslupski,