Research on Creep Behaviors of GH3230 Superalloy Sheets with Side Notches.

In order to study the effects of notches on the creep behaviors of GH3230 superalloy, a series of creep tests were conducted on GH3230 superalloy sheets with edge notches at 900 °C and 1000 °C. The creep strain curves and creep life of smooth flat plate specimens were predicted based on the θ parameter method. The results indicated that the second stage of steady-state creep of smooth flat plate specimens dominated the creep process, while the strain rate of notched specimens increased significantly in the third stage. The creep fracture strain gradually decreased with increasing creep load. The creep strain curves obtained based on the θ parameter method were in good agreement with the experimental creep strain curves. The predicted creep life of the smooth flat plate specimens and notch specimens were in good agreement with the experimental results, and all experimental results were within the double dispersion band of the predicted life. Notches exhibited a creep life enhancing effect on GH3230 superalloy under the same net stress level. Both stress concentration factor and the experimental net stress collectively determined the notch life enhancement factor. The higher the experimental net stress, the more pronounced the notch life enhancement effect.