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MgB2 superconductor is a superconductor with a critical temperature of around 39K and has the potential to replace Nb3Sn and NbTi as superconducting coils to produce high magnetic fields. In this study, monofilament wires have been made to analyze the doping effect of SiC and Carbon Nanotubes (CNT) in its manufacture using Powder-In-Tube (PIT) method. Stainless Steel (SS-316) tube was used as a tube filled with powders of starting materials of Mg, B, SiC and CNT. A total of 8 samples were prepared with variations in the addition of SiC, and CNT as much as 5, 10, and 15 wt %, and also the variations in the addition of Mg composition by 0 and 10 mol % from normal stoichiometric values. The samples were rolled and sintered at 800°C for 3 hours. The samples then were analyzed using SEM (Scanning Electron Microscopy) to analyze the surface morphology, XRD (X-Ray Diffractometer) to analyze the formed phases and crystal structures, and then resistivity versus temperature using cryogenic systems to analyze their superconductivity properties. Based on the results of the XRD analysis, the MgB2 phase is the major phase in the samples and the SiC doping causes the formation of minor phases of Mg2Si and Fe3C. The addition of SiC causes a decrease in crystalline properties of the MgB2 phase due to reaction with SiC, while the addition of CNT does not cause the formation of a new phase. Based on the results of the analysis of resistance versus temperature, it is seen that the addition of SiC causes a decrease in TC value. While the addition of CNT causes the improvement in the nature of superconductivity, but it also causes the decrease of its TC values.

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ABSTRAKTelah dilakukan percobaan pemurnian Metallurgical Grade Silicon (MG-Si) atau silikon tingkat metalurgi melalui proses pelindian. Proses pelindian menggunakan campuran larutan asam pada konsentrasi 2,45 mol/L HCl + 1,2 mol/L HF yang dilakukan dengan memvariasikan waktu pelindian pada suhu 60°C dengan kecepatan putar 300 rpm. Hasil percobaan menunjukkan bahwa proses pelindian MG-Si dengan menggunakan campuran larutan asam pada konsentrasi 2,45M HCl + 1,2M HF dapat menurunkan unsur pengotor yang terkandung di dalam MG-Si dan meningkatkan kemurnian seiring peningkatan waktu pelindian. Pada proses pelindian 12 jam, efisiensi ekstraksi unsur pengotor Al dan Fe mencapai 99,99%, sedangkan untuk unsur Ti mencapai 99,96%. Persentase efektivitas dari larutan pelindian selama 12 jam mencapai 99,96%. Pencapaian tersebut berpeluang untuk ditingkatkan dengan memvariasikan konsentrasi maupun waktu pelindian sehingga diperoleh nilai optimal.Kata kunci: silikon tingkat metalurgi, pelindian, efisiensi ekstraksi, efektivitas larutan. ABSTRACT The purification process of Metallurgical Grade Silicon (MG-Si