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Carbon was known to be one of effective additives which can improve the flux pinning of MgB₂ athigh magnetic fields. In this study, glycerin (C3H8O3) was selected as a chemical carbon source for the improve-ment of critical current density of MgB₂der was heat-treated with liquid glycerin. The glycerin-treated boron powder was mixed with an appropriateamount of magnesium powder to MgB₂ composition and the powder pallets were heat treated at 650℃ and 900℃ for 30 min in a flowing argon gas. It was found that the superconducting transition temperature (Tc) of Mg(B₁-xCx)₂prepared using glycerin-treated boron powder was 36.6K, which is slightly smaller than Tc (37.1 K) of undoped MgB₂. The critical current density (Jc) of (B₁-xCx)₂was higher than that of undoped MgB₂ and the Jc improve-ment effect was more remarkable at higher magnetic fields. The Tc decrease and Jc increase associated with theglycerin treatment for boron powder was explained in terms of the carbon substitution to boron site.
