Influence of recrystallization on high-temperature stress rupture property and fracture behavior of single crystal superalloy

摘要

A single crystal (SC) superalloy was shot peened and heat treated to induce surface recrystallization, and then the influence of surface recrystallization on the high-temperature stress rupture property and frac-ture behavior of the SC superalloy was investigated through high-temperature stress rupture tests. The results show that surface recrystallization greatly reduced the high-temperature stress rupture life of the SC superalloy, and the stress rupture life declined nearly linearly with the increase of the recrystallized fraction of the transverse section. At 1000℃/195MPa, the recrystallized specimens and the bare ones (without recrystallization) fractured in the same mode—microvoid coalescence fracture. The recrystal-lized layers cracked in the initial stage, so they nearly had no bearing capacity, which is the main cause for the remarkable decrease in the stress rupture life.