Incipient melting phase and its dissolution kinetics for a new superalloy
(1. School of Metallurgy, Northeastern University, Shenyang 110819, China;
2. Aero Engine Corporation of China, Beijing Institute of Aeronautical Materials, Beijing 100095, China)
2. Aero Engine Corporation of China, Beijing Institute of Aeronautical Materials, Beijing 100095, China)
Abstract: Based on XRD, SEM and EDS analyses, the phases in GH4151 alloy were identified. Differential scanning calorimetry (DSC) experiment and metallographic method were carried out to determine the incipient melting temperature (IMT) of the alloy. The result shows that the IMT of alloy is situated between 1150 and 1160 °C. Subsequently, the dissolution process of Laves phase was carried out, and the dissolution kinetic equations were obtained at different temperatures. And then based on the verification of experiments, the model was confirmed to be credible to predict the fraction of the Laves phase dissolution. Finally, the results of diffusion coefficients indicate that the diffusion of Nb element is a critical factor for homogenization process of GH4151 alloy.
Key words: GH4151 ingot; homogenization; incipient melting; Laves phase; kinetics