In-situ heat treatment method for optimizing residual stress of selective laser melting additive nickel-based superalloy

An in-situ heat treatment method for optimizing residual stress of selective laser melting additive nickel-based superalloy comprises the steps that a cross remelting strategy is adopted, in-situ secondary scanning is conducted on a primary forming layer through laser, and a secondary scanning path is perpendicular to a primary scanning path; meanwhile, the interlayer rotation angle before and after powder laying in the material adding process is regulated and controlled, so that the powder is completely molten, the residual stress of a three-dimensional formed part is reduced, and meanwhile the porosity is reduced; the buckling deformation degree after forming is improved, and the fatigue performance is greatly improved. 一种优化激光选区熔化增材镍基高温合金残余应力的原位热处理方法，采用交叉重熔的策略，通过激光对一次成形层进行原位二次扫描，二次扫描路径与一次扫描路径相互垂直；同时通过调控在增材过程中铺粉前后的层间旋转角，使得粉末完全熔融，减小三维成形件残余应力同时降低孔隙率；本发明改善成形后翘曲变形程度，使得疲劳性能大幅提升。