Neutron diffraction measurements of residual stress in additive and subtractive hybrid manufactured (CoCrNi)94Ti3Al3 medium entropy alloy

(CoCrNi)94Ti3Al3 medium entropy alloy (MEA) exhibits excellent properties that are superior to traditional alloys and possess the potential for service under specific working conditions. However, high-technology developments have required the integrated complicated components (e.g. sharp corners, thin-walled structures and curved shapes) with high-quality surface roughness, and dimensional accuracy. With this in mind, additive and subtractive hybrid manufacturing (ASHM), in which additive manufacturing (AM) can generate raw parts with near-net-shape dimensional characteristics whereas subtractive machining (SM) operations achieve the desired dimensional accuracy and surface finish, maybe a superior manufacturing strategy of utilizing high-performance MEA parts. It is particularly noteworthy that the SM process complicates the residual stress generated by the thermal history of the AM process. The complex stress distribution may cause component warping and cracking, deteriorating the service performance. We therefore propose to study the distribution and evolution of the residual stress in the ASHM-fabricated MEAs, to lay a reliable theoretical foundation for manufacturing high performance components.