STUDY OF RECOVERY IN DEFORMED Ni-Cr-Co SUPERALLOYS USING POSITRON ANNIHILATION

The recovery recrystallization of 3 deformed Ni-Cr-Co superalloys with different Co con- tents has been studied using positron annihilation technique and TEM.The alloys with low Co content have more defects occurred than ones with high Co content,and the former may be faster in dislocation recovery than the latter.Thus,the apparent activation energy of recrystallization increases with the increase of their Co content in alloys.The relationship be- tween apparent activation energy and stacking fault energy together with their effect on re- covery were also discussed.