Enhancement in critical current density and irreversibility field of bulk MgB2 by C and CaCO3 co-addition

• Main Authors: Tan, Kean Sheng, Chen, Soo Kien, Jun, B. H., Kim, C. J.
• Format: Article
• Language: English; English
• Published: Institute of Physics 2008
• Online Access: http://psasir.upm.edu.my/id/eprint/6647/1/Enhancement%20in%20critical%20current%20density%20and%20irreversibility%20field%20of%20bulk%20MgB2%20by%20C%20and%20CaCO3%20co.pdf; http://psasir.upm.edu.my/id/eprint/6647/; http://dx.doi.org/10.1088/0953-2048/21/10/105013

Paper ash, a source of C and CaCO3, was used for the first time as a cheap form of sub-micron particles for doping. 0–10 wt% of the ash was added to Mg + 2B and in situ reacted at 850 ◦C for 30 min in flowing Ar atmosphere. The CaCO3 decomposed and reacted with B to form CaB6 as an impurity phase. Also, the Tc and the a-axis lattice parameter decreased with increasing ash content, which suggests that C substitution at boron sites occurred. Enhancement of high-field Jc(H), Hirr(T ) and Hc2(T ) was observed with an optimum level of about 5 wt% ash addition