Morphological and Resistance Properties Analysis of MgB_2 Superconducting Wires Prepared by Industrial Drawing Process

摘要

The power deficit is caused by an electric current that flows inefficiently due to the high resistance on the cables. Superconductors as the materials that have zero resistivity value, can be a solution to make efficient cables. In this work, a superconductor Magnesium Diboride (MgB_2) wire has been made using industrial wire drawing process. The MgB_2 superconducting wire was synthesized by the powder-in-tube method. Magnesium and boron powders were ground and packed into a Stainless steel 316 tube with diameter of 8.0 mm, and then continued by carrying out the rolling process until the outer diameter became 4.0 mm. The heat treatment was carried out by pulling out the wire through tube furnace with speeding of 10 cm/2 hours at air atmosphere. The tube furnace's temperature was kept at 800 °C during the pulling process. Then, the wire was drawn until its outer diameter became 1.8 mm. Morphology and resistivity properties of the sample were analyzed as the outer diameter of sample was 2.5 mm (sample 1) and 1.8 mm (sample 2). Morphology and resistivity properties were analyzed using SEM-EDS and four-point probes measurement method, respectively. Based on SEM images, it has analyzed that the Fe metal element in the stainless-steel tube does not react with the Mg element in the MgB2 alloy core. In addition, the structure of the forming process tends to be round and compact and there are no gaps or boundaries between the tube and powder. Based on the Tc_(onset) value obtained from this study was 42 K with a high density in its morphological form.