Influence of Heat Treatment on Microstructure and Mechanical Properties at Elevated Temperatures of Nonweldable Ni‐Based Alloy Printed by Fused Filament Fabrication

The microstructure and mechanical properties of printed specimens of nonweldable MAR‐M247 alloy in the sintered state and after different heat treatments are investigated. Specimens are produced using the fused filament fabrication process, which enables the fabrication of crack‐free components. The microstructure is characterized by scanning electron microscopy, electron backscatter diffraction, and X‐ray diffraction. Tensile tests are conducted at room temperature, 500, 600, and 700 °C. All heat‐treated specimens exhibit the formation of γ′ (gamma prime) precipitates larger than 500 nm, along with various carbides and equiaxed grain structures. The as‐heat‐treated specimens at the high subsolvus temperature of 1220 °C show the highest tensile strength with the highest elongation and stable tensile strength up to 700 °C.