Al-Li-Cu-Mg-Zr合金の変形中のアコースティック・エミッション挙動に及ぼす時効の影響

概要

論文の詳細を見る
The acoustic emission (AE) method is one of the most noticeable methods of late used to detect the dynamic behaviour of the microstructure in materials. In this paper, the tensile test of an aged Al-Li-Cu-Mg-Zr alloy was carried out to clarify the relation between the detected AE activities and the dynamic behaviour of the microstructures including dislocations, precipitates and secondary phases. The AE activities had the maximum value in the underaged condition near the yield point of the stres-sstrain curves. Afterward, the AE activities decreased progessively with aging. The AE did not occur in the post-and overaged conditions. Both the continuous type and the burst type signals which depend upon the avalanche of the dislocation motion and the shear of precipitates, respectively, have been detected at the same time. By the transmission electron microscopy, superlattice dislocations, metastable δ' phases and the increase of dislocation density were observed in the underaged condition where the AE activities showed a peak. According to these results, it was estimated that the AE sources of this alloy during tensile deformation were the shear of metastable ' phases and the avalanche of dislocation motion.
一般社団法人日本機械学会の論文
1989-05-25