MANUFACTURE OF SEMIFINISHED ITEMS OF ALLOYS V-4TI-4CR AND V-10TI-5CR FOR USE AS A STRUCTURAL MATERIAL IN FUSION APPLICATIONS

Vanadium-titanium-chromium alloys are considered as structural materia ls with the most appropriate properties for fusion applications, Howev er, the final ratio V-Ti-Cr in an alloy is not yet determined. On the one hand, it is offered to optimize structure on the basis of an alloy V-4Ti-4Cr. On the other hand, it is proposed that the optimum of tota l Ti and Cr content should be near 15%, and the Ti to Cr ratio should be 2:1. Melting, casting and processing by pressure of ingots of vanad ium alloys V-4Ti-4Cr and V-10Ti-5Cr weighing as much as 50 kg are cons idered in the report, The ingots in diameters up to 130 mm were obtain ed by melting in vacuum-are furnaces. Results on chemical uniformity a nd structure of the ingots are presented. A basic scheme of semifinish ed items manufacture is submitted, Rod and tube hot extrusion conditio ns are presented. A new technology for protection of ingot and billet surface from gases during hot processing is used to discard applicatio n of protective stainless steel and to lower temperature of processing , Sheet and tube products were made from extruded billets by cold roll ing with intermediate heat treatment. The list of obtained products, i ncluding sheets 0.5-5 mm thick, rods 10-18 mm in diameter and tubes fr om 50 mm up to 6.0 mm in diameter is presented, The availability of la rge-scale ingots processing with weight above 300 kg is discussed.