Exceptional High‐Temperature Strength and Creep Properties of a Weldable Ni‐Based Wrought Superalloy

Herein, the tensile and creep properties of a weldable Ni‐based wrought superalloy specifically engineered to endure service temperatures surpassing 800 °C have been investigated. The alloy overcomes the dilemma of conflicting welding and mechanical properties, showcasing remarkable weldability alongside sustained superior mechanical performance. At ambient temperature, the alloy boasts a tensile strength of 1390 MPa, while maintaining a commendable strength of 850 MPa at 800 °C. The creep response under 800 °C/200 MPa conditions unfolds in three stages, marked by an extended period of steady‐state stage spanning over 210 h. Notably, both the minimum steady‐state creep rate and creep rupture strength surpass those of other conventional wrought, weldable superalloys, such as Haynes 282. The superior creep resistance is likely due to the synergistic effect of the Orowan looping and the shearing of stacking faults. The electron backscattered diffraction analysis shows that during the creep process of the alloy, the proportion of high Schmid factors increases, allowing more grains to meet the conditions for dislocation slip and leading to the acceleration of plastic deformation. After creep, the proportion of twin boundaries decreases, and the obstacle effect of the alloy on dislocations is significantly weakened.