EMBRITTLEMENT OF VANADIUM ALLOYS DOPED WITH HELIUM

Helium embrittlement in several binary vanadium alloys together with pure vanadium has been studied by tensile tests between room temperature and 80-degrees-C after helium doping by the tritium trick technique. Although all the alloys without helium doping showed good ductility in the full temperature range studied, all the alloys doped with helium became brittle at 800-degrees-C. Helium release during tensile deformation has been measured simultaneously with the load-displacement signal. A good correlation has been found between the helium release during deformation and embrittlement. Another correlation has been found between the helium release and atomic size factor; that is, the smaller solute atoms result in lower helium release. This study has also proved that the measurement of helium release during deformation provides valuable information on the behavior of helium during deformation.