Abstract:The crack propagation performance of the independently-developed 3rd-generation powder metallurgy superalloy FGH4113A was studied, including the effects of preparation process, temperature, and frequency on crack propagation performance, and a comparison was made with similar superalloys. The preparation process involved a combination of hot isostatic pressing, hot extrusion, isothermal forging (ITF), and heat treatment. Test temperatures included room temperature, 650 ℃, and 700 ℃, with test frequencies of 0.33 and 20 Hz. The effects of process, temperature, and frequency on the high-temperature crack propagation performance of the alloy were analyzed. The crack propagation performance of similar alloys with grades such as FGH95, FGH96, FGH97, FGH98, ME3, and LSHR was compared. The results show that prior particle boundary (PPB) and coarse primary γ′ phase around the grain boundary are unfavorable factors for the crack growth performance of the alloy, and increasing the grain size is beneficial to reducing the crack propagation rate. Extrusion and forging process can effectively eliminate PPB, thereby enhancing the crack propagation resistance of the alloy. The crack propagation rate at room temperature is much lower than that at 650 and 700 ℃, and the crack propagation rate at test frequency of 0.33 Hz is significantly higher than that at 20 Hz. Increasing the temperature and decreasing the test frequency will increase the crack propagation rate of the alloy. In the stable crack propagation stage, the FGH4113A alloy in ITF state exceeds FGH98, LSHR, and ME3 alloys, and reaches the advanced level of the 3rd-generation powder metallurgy superalloy.