The invention relates to a
process window screening method for
nickel-based high-temperature
alloy single crystal preparation. According to the method, based on a double-
ellipsoid molten pool analysis heat
source model and solidification condition calculation, the geometrical morphology and solidification behavior of the
molten pool caused by
electron beam scanning can be simulated in a multi-parameter space in a high-flux mode. The
grain orientation evolution trend of the material after the
powder bed is molten can be accurately predicted by calculating parameters such as the
penetration depth, the penetration width, the
molten pool leading edge angle and the
temperature gradient under different energy input conditions, and a
single crystal forming window suitable for the
nickel-based
superalloy is constructed. By adopting the method, process parameters such as energy input, scanning speed, scanning strategy and the like can be screened and optimized, and a multi-dimensional
process window is established so as to identify stable growth conditions required by
single crystal preparation. According to the method, the internal relation between the geometric behavior of the molten
pool and the preferred orientation of the
crystal grains can be disclosed, and
technical support is provided for realizing controllable forming of a single-
crystal structure, reducing the defect generation risk and improving the
structural integrity and performance of an additive manufacturing part.