The effect of nano-Pt/nano-SiC co-additions on superconducting properties of bulk MgB2

This research presents a detailed analysis and discussion of the crystallographic, flux pinning mechanism, the microstructure and superconducting properties of nano-Pt/nano-SiC co-added (in different addition levels) bulk MgB2 samples. All disk-shaped MgB2 bulk samples were manufactured using the conventional solid-state reaction method and the sintering process was implemented at 700 & DEG;C for 3 h in pure Ar atmosphere. Nano-Pt addition levels were 0.0; 0.5; 1.0; 3.0; 5.0; 7.0 wt% of MgB2 powders and nano-SiC addition level was 10 wt% of MgB2 powders. X-ray diffraction (XRD) analysis shows that Mg2Si, Pt3Si and Mg2PtSi impurity phases were detected in nano-Pt/nano-SiC co-added MgB2 samples. These impurity phases created zones acting as influential pinning centers for the flux lines. The critical current density (J(c)) indicated improvement at high field (B > 4 T) for 10 wt% nano-SiC added sample and all nano-Pt/nano-SiC co-added samples. The values of J(c) in 6 T field at 5 K were calculated to be 3.1 x 10(3) A/cm(2) for pristine MgB2 sample, 1.5 x 10(4) A/cm(2) for the 10 wt% nano-SiC added MgB2 sample and 1.6 x 10(4) A/cm(2) for the 1.0 wt% nano-Pt and 10 wt% nano-SiC co-added MgB2 sample. At applied magnetic fields higher than about 4 T at 5 K and 10 K, the best J(c) performance among all samples is given by 1.0 wt% nano-Pt and 10 wt% nano-SiC co-added MgB2 sample. The pristine MgB2 sample has a the critical temperatures (T-c) of 38.1 K and T-c has dropped with nano-Pt/nano-SiC co-added bulk MgB2 samples. The flux pinning mechanisms of both pristine and all nano-Pt/nano-SiC co-added bulk MgB2 samples were seen to be the normal point pinning in magnetic fields lower than B-max (the field at which the pinning force reaches its maximum) at 15 K.

Automated summary

This research study examines the crystallography, flux pinning mechanism, microstructure, and superconducting properties of MgB2 samples co-added with nano-Pt/nano-SiC. XRD analysis reveals the presence of impurity phases (Mg2Si, Pt3Si, and Mg2PtSi) in the co-added samples, which act as influential pinning centers for the flux lines. The addition of nano-SiC and nano-Pt improves the critical current density (Jc) at high magnetic fields (B > 4 T).