Phase field modeling of shearing processes of a dual-lobed γ″|γ′|γ″ coprecipitate
Feng L, Shi R, Zenk C, Mills MJ, Wang Y (2023)
Publication Type: Journal article
Publication year: 2023
Journal
Book Volume: 246
Article Number: 118693
DOI: 10.1016/j.actamat.2023.118693
Abstract
The Ni-based superalloy IN718 is one of the most widely used commercial alloy in the aerospace industry since its development in 1960s. The excellent mechanical properties have been attributed in a great deal to strengthening by coherent γ′ and γ″ precipitates. The deformation mechanisms of these two phases have been well studied individually. Recent experimental characterization has shown coprecipitates of these two phases in a variety of morphologies and it was argued that these coprecipitates may lead to improved strengthening as compared to their monolithic counterparts. However, the deformation mechanisms of these coprecipitates are still not well understood. In this study, we performed microscopic phase field simulations, with generalized-stacking-fault (GSF) energy surfaces from ab initio calculations as inputs, to systematically study the shearing processes of a periodical array of dual-lobed coprecipitates as well as monolithic precipitates. We found that the coupling between the γ′ and γ″ phases in the coprecipitates forces dislocations to take high energy shearing pathways in both phases that would not occur if they were in monolithic forms. The coupling also creates stacking fault configurations in the coprecipitates that require high stress to form. Thus, the presence of coprecipitates in general should increase the resistance to dislocation shearing and lead to higher strength levels. Various fault configurations observed during the shearing process are documented as a reference for future comparison with experimental observations. The link between stacking fault shearing and microtwinning is also discussed. The mechanisms analyzed in this study deepens our understanding of coprecipitation effects on alloy strength and may form a cornerstone for multi-precipitate strengthened alloy design strategies.
Authors with CRIS profile
Involved external institutions
Ohio State University
United States (USA) (US)
Harbin Institute of Technology (HIT) / 哈工大
China (CN)
United States (USA) (US)
Harbin Institute of Technology (HIT) / 哈工大
China (CN)
How to cite
APA:
Feng, L., Shi, R., Zenk, C., Mills, M.J., & Wang, Y. (2023). Phase field modeling of shearing processes of a dual-lobed γ″|γ′|γ″ coprecipitate. Acta Materialia, 246. https://dx.doi.org/10.1016/j.actamat.2023.118693
MLA:
Feng, Longsheng, et al. "Phase field modeling of shearing processes of a dual-lobed γ″|γ′|γ″ coprecipitate." Acta Materialia 246 (2023).
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