IMPROVED NIOBIUM 47-WEIGHT-PERCENT TITANIUM COMPOSITION BY IRON ADDITION

The effect of iron addition on the ductility and superconducting prope rties of Niobium Titanium alloys has been explored. The conclusion of this study is that iron up to 2000 parts per million by weight is not deleterious to the fabricability of multifilamentary composites. The h ardening rate of the iron rich alloy as filaments in a copper matrix w as observed to be the same as for low iron versions of the same nomina l composition. The development of the pinning microstructure was monit ored and compared to the critical current properties of the wire. The results for multifilamentary wires are compared for heats with and wit hout high iron contents. The results were reproduced in the production environment from a full scale ingot. The critical current density for the iron enriched material is elevated relative to the low iron mater ial at high fields. The beneficial influence of iron on the supercondu cting properties is discussed in light of the microstructure. A design ed experiment was conducted to explore the range over which the chemis try can be varied without affecting the behavior. The goal is to broad en the range of iron allowed in Niobium Titanium alloys for supercondu cting applications.