METHOD FOR HEAT TREATING NB-CONTAINING METAL, PRODUCTION OF NB-CONTAINING SHEET AND PRODUCTION OF NB3X SERIES SUPERCONDUCTING WIRE

摘要

PROBLEM TO BE SOLVED: To suppress the increase in the hardness of a sheet and to improve its workability, in such a manner that the structural member for a heat treating furnace composed of the material different from Nb contg. metal and the Nb- contg. metal are not directly faced, by surrounding the vicinity of Nb-contg. metal by a bulkhead not contg. components other than the components in the Nb-contg. metal and executing heat treatment. SOLUTION: An Nb-contg. sheet 2 is charged to the inside of a heat treating furnace and is subjected to heat treatment. The Nb-contg. sheet 2 is charged to the inside of an Nb vessel 1, e.g. made of pure Nb. Thus, the Nb-contg. sheet 2 is not directly faced with a heater 3, a reflector 4, a furnace wall 5 or the like in the process of the heat treatment. The Nb vessel 1 is not limited to pure Nb and is preferably composed of a material not contg. components other than the components in the Nb-contg. sheet 2, also contg. Nb and contg. the other components other than Nb by the content less than that of the other components in the Nb-contg. sheet 2. Then, the heat treatment is executed prerferably at =400 deg.C at a degree of vacuum of =110-5 Torr.