Reference vanadium alloy V-4Cr-4Ti for fusion application

Abstract

Vanadium alloys exhibit important advantages as a candidate structural material for fusion first-waWblanket applications. These advantages include high temperature and high wall load capability, favorable safety and environmental features, resistance to irradiation damage, and alloys of interest are readily fabricable. A substantial data base has been developed on laboratory-scale heats of V-Ti, V-Cr-Ti and V-Ti-Si alloys before and after irradiation.

Deuterium and helium retentions of V–4Cr–4Ti alloy used as first wall of breeding blanket in a fusion reactor

“…Vanadium alloy is an attractive structural material used for fusion reactor because of its low induced radioactivity and good thermal and mechanical properties at high temperatures [1][2][3][4][5]. The vanadium alloy, V-4Cr-4Ti, may be a promising material because it shows excellent mechanical tolerance to neutron damage [2,3] and low helium and hydrogen production rate during 14 MeV neutron irradiation [5].…”

“…The vanadium alloy, V-4Cr-4Ti, may be a promising material because it shows excellent mechanical tolerance to neutron damage [2,3] and low helium and hydrogen production rate during 14 MeV neutron irradiation [5]. One of the important concerns regarding the vanadium alloy is its large retention of tritium (deuterium) caused by gas absorption and ion implantation.…”

The Role of Oxygen Uptake and Scale Formation on the Embrittlement of Vanadium Alloys

“…Impurity levels were reported as 780 wppm Si, 310 wppm O, 85 wppm N and 80 wppm C. 20 Specimens were 0.76-mm thick, miniature tensile specimens (type SS-3: 2.5-cm long × 0.4-cm wide) punched from cold-rolled sheet or 10 mm × 10 mm × 0.76 mm coupons from the same sheet. Prior to exposure, all specimens were vacuum annealed at 1050 • C to produce a uniform grain size of ≈15µm with no additional surface preparation.…”

An analysis of the microstructure of spark plasma sintered and hot isostatically pressed V 4Cr 4Ti 1.8Y 0.4Ti3SiC2 alloy and its thermal stability

“…Silicon carbide composites are promising for very high temperature operations (1500e1650 C) but there are serious issues regarding their fabrication, long-term stability and irradiation performance, particularly concerning swelling, that need to be addressed [7]. Vanadium alloys are a promising alternative to steels and silicon carbide structures; VeCreTi compositions in particular have been shown to have high creep strength for long-term operation up to temperatures of 700 C, with good levels of strength and irradiation tolerance and a relatively low ductility loss because of radiationinduced defects [8,9]. Vanadium itself is a very low activating element within the first wall/blanket environment, providing a significant advantage in decommissioning and remote handling of components [10]; however, concerns remain regarding the irradiation tolerance, tritium retention and the desirability of continuing to increase the operational design window for vanadium alloys, particularly at higher temperatures above 700 C.…”