Research Finds Mechanical Forces Accelerate Alloy Failure in High-Temperature Nickel-Based Alloys

Research published in Engineering Failure Analysis has revealed that mechanical forces significantly accelerate the failure of high-temperature nickel-based alloys through altered oxidation rates and enhanced chemical reactions. The study, conducted by researchers from Lanzhou University of Technology, used Reactive Force Field Molecular Dynamics (ReaxFF-MD) to simulate the mechanical behavior and chemical reactions of gamma'-Ni3Al alloys under coupled oxidation and stretching. Funding for the research was provided by the National Natural Science Foundation of China, Gansu Provincial Natural Science Foundation, and Gansu Provincial Department of Education.

Key Takeaways:

• The introduction of mechanical forces accelerates alloy failure by altering the oxidation rate of the alloy, with early oxidation resulting in decreased strength and ductility.
• The applied stress increases the oxidation rate, charge transfer, coordination number, and the number of atoms involved in the reaction of the alloy, with oxygen concentration exhibiting a positive correlation with these enhancements.
• Oxygen atoms preferentially accumulate in NiAl-rich regions, driving the formation of high-valent Al ions, and necking phenomena predominantly initiate in high-stress zones characterized by dynamic Al-O bond rupture/reformation.
• Subsequent re-oxidation leads to localized severe oxidation at necking sites.
• The exothermic phenomenon of stretching and oxidation promotes the participation of Ni in the oxidation.
• The research has significant implications for the development of high-temperature nickel-based alloys in fields such as aerospace and energy production.

Statistics:

• The study used Reactive Force Field Molecular Dynamics (ReaxFF-MD) simulations to model the mechanical behavior and chemical reactions of gamma'-Ni3Al alloys.
• The research was funded by the National Natural Science Foundation of China, Gansu Provincial Natural Science Foundation, and Gansu Provincial Department of Education.
• The study involved a team of researchers from Lanzhou University of Technology, including Zongxiao Zhu, Dingfeng Qu, Min Zheng, Weihua Chen, Chunli Lei, and Hui Tan.
• The research has been peer-reviewed and published in Engineering Failure Analysis.

Sources:

• NewsRx. Lanzhou University of Technology Details Findings in Chemicals and Chemistry (Effect of Tensile Strain On the Early Oxidation of the Nickel-based High-temperature Alloy G'-ni3al: Insights From Reaxff Molecular Dynamics). Journal of Physics Research. August 5, 2025; p 2130.