Microstructural Evolution and Its Impact on Mechanical Properties of INCONEL 600 Under Thermomechanical Treatments

INCONEL 600 is extensively employed across various industries due to its remarkable resistance to both corrosion and elevated temperatures. The alloy’s superior high-temperature performance and extended service life are largely attributed to its stable single-phase microstructure, which remains intact up to 1703 K (1430 ℃). In this study, the microstructural evolution of INCONEL Alloy 600 was systematically examined under a range of thermal and thermomechanical treatments. These microstructural analyses were complemented by mechanical property assessments, including tensile and creep tests. Specimens were solutionized at 1200ºC for 1 h, resulting in a microstructure characterized by an average grain size distribution between 45–60 μm. Additionally, primary and secondary carbides rich in Cr, Nb, and Ti were observed within the γ matrix. The alloy was subsequently subjected to cold forging at room temperature, with varying levels of strain ranging from 20% to 50%, followed by post-deformation heat treatments. Microstructural features were analyzed using advanced electron microscopy techniques, while nanoindentation tests were employed to investigate indentation load-depth profiles at a finer scale, providing insight into localized mechanical behavior. Furthermore, analytical modelling was conducted to elucidate the micromechanisms governing plastic deformation, with a particular focus on the role of microstructural attributes, such as dislocation density and carbide distribution, in influencing the plasticity of the alloy.