Earticle

초록

영어

The effect of the size and shape of magnesium(Mg) powder on the formation of MgB2 and the critical current density(Jc,) of MgB2 bulk was studied. As a precursor for the formation of MgB2, Mg and MgB4 powder, which was synthesized through the reaction of boron (B) with Mg powders, was used. MgB4 was mixed with Mg powders of various sizes, pressed into pellets and heat-treated at 650℃-750℃ in flowing argon gas. The XRD analysis of the heat-treated MgB2 samples showed that the volume fraction of MgB2 was the highest as 92.74 % when spherical Mg powder with an average size of 25.7 μm was used, whereas the volume fraction was the lowest as 79.64 % when plate-like Mg powder with a size of 34.1 μm was used. The superconducting transition temperature (Tc) of MgB2 was not sensitive to the characteristics of the Mg powders used. All of the prepared MgB2 samples showed a high Tc of 38.3 K and a small superconducting transition width of 0.2 K-0.5 K. Jc (5 K and 1 T) of MgB2 was the highest as 3.93×104A/cm2 when spherical Mg powder with a size of 25.7 μm was used, whereas Jc was the lowest as 2.18×104 A/cm2 when plate-like Mg powder with a size of 34.1 μm was used. The relationship between the Jc of MgB2 and the characteristics of the Mg powders used was explained in terms of the volume fraction of MgB2 and the apparent density of the MgB2 pellets.

목차

Abstract
 1. INTRODUCTION
 2. EXPERIMENTAL PROCEDURE
 3. RESULTS AND DISCUSSION
 4. CONCLUSIONS
 ACKNOWLEDGMENT
 REFERENCES

키워드

저자

• D. N. Kim [ Korea Atomic Energy Research Institute, Daejeon, Korea, Korea University of Technology and Education, Cheonan, Korea ]
• B.-H. Jun [ Korea Atomic Energy Research Institute, Daejeon, Korea ]
• S.-D. Park [ Korea Atomic Energy Research Institute, Daejeon, Korea ]
• C.-J. Kim [ Korea Atomic Energy Research Institute, Daejeon, Korea ]
• H. W. Park [ Korea University of Technology and Education, Cheonan, Korea ] Corresponding author

참고문헌

발행기관

간행물

표지보기 관심저널 등록

• 간행물명

  한국초전도·저온논문지 (구 한국초전도저온공학회논문지) [Progress in Superconductivity and Cryogenics]

• 간기

  계간

• pISSN

  1229-3008

• eISSN

  2287-6251

• 수록기간

  1999~2026

• 등재여부

  KCI 등재,SCOPUS

• 십진분류

  KDC 427 DDC 537