MANUFACTURE OF SUPERCONDUCTIVE CIRCULAR MOLDED STRANDED WIRE

摘要

PURPOSE:To prevent the deterioration in critical current characteristic by carrying out the compressed molding of a stranded wire through a hole type rolling roller that has a roller diameter not less than five times as large as a finished outer diameter. CONSTITUTION:The compressed molding of a stranded wire 2 is carried out by a hole type rolling roller 7 that has a roller diameter not less than five times as large as a finished outer diameter. When the compressed molding is carried out by such a hole type rolling roller 7, even the inside of the stranded wire 2 is compressed and is molded, and the deterioration in critical current characteristic due to the compressed molding does not occur even when the compressed molding is carried out for an element wire filling ratio of no less than 80%. In order to prevent the deterioration in critical current characteristic even when the filling ratio is not less than 90%, it is desired that the twisting pitch of the stranded wire 2 is not less than five times as large as the finished outer diameter. A superconductive circular molded stranded wire 2 of high filling ratio and of high critical current can thus be obtained.