The coarsening behavior of á phases in Ni-Al binary model single crystal superalloy at 1000 C

Ex-situ and quasi in-situ thermal exposure experiments have been conducted to explore the coarsening behavior of gamma ' phases in the Ni-Al binary model single crystal superalloy at 1000 degrees C. It is obtained in ex-situ experiments that the number density and volume fraction of gamma ' phases decrease with the exposure time increasing, while the average size increases. The coarsening of gamma ' phases in the width direction obeys the cubic law described by the LSW theory, while the average size change in length is much greater than that in width. In quasi in-situ experiments, it is observed that small gamma ' phases shrink or dissolute, the large ones tend to grow up. The coalescence of gamma ' phases is also observed, which induces a sharp increase in the length direction.(c) 2022 Elsevier B.V. All rights reserved.