Tensile and Fatigue Properties of Haynes ® 233 Manufactured by Wire-arc Additive Manufacturing

Abstract

Haynes® 233 is a newly developed nickel-based superalloy currently in the early stages of commercial adoption. With the growing interest in fabricating large and complex components using wire-arc additive manufacturing (WAAM), this alloy presents a promising option for industrial applications. This study investigates the microstructure, tensile, and fatigue properties of heat-treated (HT) WAAM Haynes ® 233 and compares them to its wrought counterpart. Yield strength (YS), ultimate tensile strength (UTS), and fatigue strength of WAAM Haynes ® 233 are 709.4 MPa, 890.1 MPa, and 253.8 MPa, respectively. These values indicate a 63.8 % increase in YS, a 1.11 % decrease in UTS, and a 21.7 % increase in fatigue strength compared to the wrought material. The slight decrease in UTS is attributed to process-induced defects, while the improved fatigue strength in the HT material is due to the increased volume fraction and spatial distribution of carbides in the microstructure. Fractography of the tensile fracture surfaces indicated ductile failure in the wrought material and brittle failure in the HT WAAM material, with defects acting as initiation sites for fatigue failure in both materials