Effects of neutron irradiation and hydrogen on ductile-brittle transition temperatures of V-Cr-Ti alloys

Abstract

The effects of neutron irradiation and hydrogen on the ductile-brittle transition temperatures (DBTTs) of unalloyed vanadium and V-Cr-Ti alloys were determined from Charpy-impact tests on 1 3 ASTM-standard-size specimens and from impact tests on 3-mm diameter discs. The tests were conducted on specimens containing < 30 appm hydrogen and 600–1200 appm hydrogen and on specimens after neutron irradiation to 28–46 atom displacements per atom at 420, 520, and 600°C. The DBTTs were minimum (< −220°C) for V-(1–5)Ti alloys and for V-4Cr- 4Ti alloy with < 30 appm hydrogen. The effect of 600–1200 appm hydrogen in the specimens was to raise the DBTTs by 60–100°C. The DBTTs were minimum (< −200°C) for V-(3–5)Ti and V-4Cr-4Ti alloys after neutron irradiation.