Research On Fabrication Of Nb₃Al Wire By The Rapid Heating-quenching Transformation Method

After more than hundred years of development,superconducting technology has been widely used in military,energy,electric power,medical,transportation,scientific research and other fields.Under the requirements of commercial development and commercial application,A 15-type compound Nb3Al superconducting material has attracted widely attention due to its good performance.Compared with Nb3Sn which has been a practical superconducting material,Nb3Al not only has an extremely high critical current density and excellent strain tolerance for high-field but also can meet the requirement of practical superconducting material.Therefore Nb3Al is expected to be considered as an alternative to Nb3Sn.This paper is mainly to study the fabrication of Nb3Al wire by the rapid heating-quenching transformation method.Specific studies are as follows:(1)The equipment that manufacture Nb3Al wires by the rapid heating-quenching transformation method is independently developed.Nb-Al binary phase diagram was studied,and it is found that Nb3Al is unstable.It is likely to form stoichiometric Nb3Al superconducting material only at high temperature of 1920?.Given the existing conditions and range of Nb3Al phase and compared with heat treatment methods in the process of manufacturing Nb3Al superconducting wires,the rapid heating-quenching transformation method is the most ideal method.So the equipment of manufacturing Nb3Al superconducting wires is developed by using this method.(2)The heating temperature of manufacturing Nb3Al wires is measured by TCD2252D color CCD.Firstly,we review the con-contact temperature measurement method and discuss the measurement temperature principle of CCD,then we study the calculation method of color CCD measuring temperature,finally,use of Visual Basic language program achieved to measurement heating temperature in the real-time process.(3)We study the properties of superconducting wires which are fabricated with the different Nb-Al precursor wires at the different heating temperature using the equipment of manufacturing Nb3Al.Through the comparative analysis,the Nb-Al precursor wires fabricated by the Jelly-Roll method can be prepared Nb3Al superconducting wires with good performance at the temperature of 1920? in the heating treatment process.