Udimet 520の高温特性に及ぼす熱処理の影響

概要

論文の詳細を見る
From the studies of heat-treatment for a Ni-base superalloy “Udimet 520”, it was found that control-cooling from solution temperature was effective, comparing with conventional air cooling, to improve the mechanical properties. That is, as dcreasing the cooling rate from solution temperature, toughness and creep rupture elongation were increased and creep rupture strength was decreased. Therefore, it was suggested that the best combination of toughness, creep rupture elongation and creep rupture strength would be obtained by controlling the cooling rate from solution temperature and controlling the content of Al and Ti. The reasons for the improvement of toughness and creep rupture elongation by control-cooling was supposed to the changes in grain boundary structure. That is, after control-cooling, it was observed by TEM that grain boundary was irregular and gamma prime precipitated on grain boundaries.