The power industry has been faced with continued challenges around decarbonization and additive manufacturing (AM) has recently seen increased use over the last decade. The use of AM has led to significant design changes in components to improve the overall efficiency of gas turbines and more recently, hot-section components have been fabricated using AM nickel-base superalloys, which have shown substantial benefits. This paper will discuss and summarize extensive studies led by EPRI in a novel AM nickel-base superalloy (ABD·900-AM). A comprehensive high temperature creep testing study including >67,000 hours of creep data concluded that ABD-900AM shows improved properties compared to similar ~35% volume fraction gamma prime strengthened nickel-base superalloys fabricated using additive methods. Several different creep mechanisms were identified and various factors influencing high temperature behavior, such as grain size, orientation, processing method, heat treatment, carbide structure, chemistry and porosity were explored. Additional studies on the printability, recyclability of powder, wide range of process parameters and several other factors have also been studied and results are summarized. A summary on the alloy -by-design approach and accelerated material acceptance of ABD-900AM through extensive testing and characterization is further discussed. Numerous field studies and examples of field use cases in ABD-900AM are also evaluated to showcase industry adoption of ABD-900AM.

The advancement of additive manufacturing (AM) technology has heightened interest in producing components from nickel-based superalloys for high-temperature applications; however, developing high gamma prime (γ’) strengthened alloys suitable for AM at temperatures of 1000°C or higher poses significant challenges due to their “non-weldable” nature. Traditional compositions intended for casting or wrought processes are often unsuitable for AM due to their rapid heating and cooling cycles, leading to performance compromises. This study introduces ABD-1000AM, a novel high gamma prime Ni-based superalloy designed using the Alloys-by-Design computational approach to excel in AM applications at elevated temperatures. Tailored for AM, particularly powder bed fusion, ABD-1000AM demonstrates exceptional processing capability and high-temperature mechanical and environmental performance at 1000°C. The study discusses the alloy design approach, highlighting the optimization of key performance parameters, composition, and process-microstructure-performance relationships to achieve ABD-1000AM’s unique combination of processability and creep resistance. Insights from ABD-1000AM’s development inform future directions for superalloy development in complex AM components.