Microstructure evolution of an Inconel 718 alloy prepared by electron beam smelting

A new electron beam smelting technology was employed to prepare the Inconel 718 alloy, and microstructure evolution nucleation coarsening mechanisms of γ', γ″ δ phase this alloy investigated. The microstructures can be refined by means smelting, good stability is observed at 700 °C, which least 20 °C beyond limiting temperature that sustain for prolonged periods. γ' precipitates could formed in less than 1 h when aged 800 follows conventional Lifshitz-Wagner theory, while Lifshitz-Slyozov encounter Modified theory. When thermal 900 both are absent. arised from stacking faults induced formation a/6 〈211〉 Shockley partial dislocations or lattice distortion lower temperature. While higher temperature, arrangement a/2 〈110〉 matrix responsible phase. discontinuous during exposure. growth rate lath controlled lengthwise direction first, then intermittent length width nucleated matrix, determined its thickening firstly, coherent occurs along with aging proceeding