Additive manufacturing nickel-based superalloy heat treatment process

The invention provides a heat treatment process for additive manufacturing of nickel-based superalloy, and belongs to the field of superalloy. According to the method, a proper amount of Sc is introduced to be matched with proper 3D printing parameters, and pre-annealing and solution treatment or pre-annealing, solution treatment and aging treatment are performed, so that the heat treatment cracking problem is effectively solved, and the high-quality nickel-based high-temperature alloy with the tensile strength larger than 1500 MPa is obtained. According to the method, pre-annealing treatment at the temperature of 660-760 DEG C is tried for the first time, then solution treatment at the temperature of 1150-1170 DEG C is carried out, the solution treatment time is controlled to be 1-6 h, and a crack-free solid-solution-state product with the tensile strength exceeding 1500 MPa and the elongation larger than 20% is obtained; and finally, a product with high yield strength and tensile strength and the elongation