O-free polyacrylonitrile doping to improve the Jc(B) and Hc2 of MgB2 wires

Micro-indentation study of Mg-addition MgB2 superconducting wires

“…Poor connectivity between grains and lack of pinning centres are the cause of low critical current densities in these wires. In the literature, many attempts have been made to improve the pining properties and J c of MgB 2 wires by methods such as elemental addition or doping (Ti, Al, and Zr) [10], lauric acid doping [11], polymethyl-methacrylate doping [12], and O-free polyacrylonitrile doping [13]. It is expected that the mechanical properties were improved with the aforementioned experiment techniques.…”