The design of oxidation resistant Ni superalloys for additive manufacturing

Abstract

To design new oxidation resistant Ni superalloys adapted for additive manufacturing, a computational design approach has been constructed in this work. A series of selection criteria and optimization criteria were defined and validated for composition screening, and the genetic algorithm was incorporated into the model to effectively explore the compositional search domain. Accordingly, A new Ni superalloy, AMS-OR, has been developed with the optimal combination of printability, oxidation resistance and mechanical properties. Experimental results show that AMS-OR exhibits excellent printability, achieving crack-free samples across a rather wide range of printing parameters. The strength and ductility of AMS-OR alloy can well outperform the existing Ni commercials as well. After oxidation test, a complete and stable Al₂O₃ oxide layer forms in the inner layer of the oxide scale with no spallation, demonstrating the favorable oxidation resistance of this alloy which is comparable to the commercial counterparts. The experimentally validated properties in additive manufacturing, mechanical properties and oxidation resistance of novel alloy confirm the effectiveness of the alloy design model in developing high-performance Ni superalloys, which provides a new pathway for developing novel printable alloys with excellent service performance.