Research on Microstructural and Performance Evolution of IN783 Bolt in Service

Abstract In this paper, the evolution of the microstructural and performance of IN783 hightemperature bolts in service was studied. The results showed that under high-temperature service environment, with the increase of service time, the superalloy of IN783 bolt and the precipitation quantity of second phase increased. The second phase mainly existed in the form of particles and rods, which were distributed in an obvious oriented way. With the extension of service time, the strength of the alloy increased, but the hardness decreased, the plasticity and toughness decreased significantly, so it is difficult for the IN783 high-temperature bolts to reach the normal level of safe service. Therefore, the IN783 high-temperature bolts that have been in service for a long time should be strictly supervised and replaced appropriately to reduce losses.