RECOVERY AND RECRYSTALLIZATION OF VANADIUM ALLOYS

A vanadium alloy containing 4 wt% Cr and 4 wt% Ti has been identified as a promising candidate structural alloy for liquid metal-cooled blan kets in fusion power reactors. Studies of recovery, recrystallization and precipitation kinetics are in progress to provide the metallurgica l basis for the development of improved properties. Recovery and recry stallization behavior has been examined using conventional slow heatin g/cooling cycles, rapid heating and quenching, and differential scanni ng calorimetry. The reduction in hardness is a two-stage process with the first stage associated with recovery due to cell formation and ann ihilation of dislocations, and the second stage involving the growth o f recrystallization nuclei. This is consistent with the results of the differential scanning calorimetry which exhibit a broad exothermic pe ak at low temperature range due to recovery followed by a sharp exothe rm associated with recrystallization.