Characterizing accelerated precipitation in proton irradiated steel

Laver, Mark; Connolly, Brian J.; Cooper, Christopher R.; Kohlbrecher, J.; Samothrakitis, Stavros; Wilford, K.

doi:10.1016/j.jnucmat.2021.153195

Cited by 4 publications

(1 citation statement)

References 116 publications

(274 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…When the time and/or temperature is insufficient, the alloy can form a metastable microstructure to relieve the supersaturation 5 . Irradiation can also accelerate the kinetics of phase transformation [6][7][8][9] . In any case, the parent microstructure is a supersaturated solid solution, and the product is the equilibrium microstructure but the pathway from parent to product can change depending on the imposed conditions.…”

Section: Introductionmentioning

confidence: 99%

Non-classical nucleation of ordered L12 precipitates in the FCC based Al0.25CoFeNi high entropy alloy

Dasari

Sharma

Gorsse

et al. 2023

Journal of Applied Physics

View full text Add to dashboard Cite

The complex interplay between competing phase stabilities of FCC, L12, BCC, and B2 phases in the Al0.25CoFeNi (7Al-31Co-31Fe-31Ni in at. %) high entropy alloy (HEA) leads to non-classical phase transformation pathways and resultant novel microstructures. Specifically, the competition between the homogenous precipitation of L12 and heterogenous precipitation of BCC/B2 can be studied at a temperature of 500 °C in the Al0.25CoFeNi alloy. Upon isothermally annealing the single FCC phase microstructure of this HEA at 500 °C up to 50 h, the transformation initiates with the formation of a transient ordered L12 phase with minor Ni–Al enrichment, which is far-from equilibrium, as revealed by atom probe tomography, and can be considered non-classical nucleation. The near equilibrium L12 phase eventually replaces the transient L12 during continued annealing at the same temperature. However, the resultant FCC + L12 microstructure is metastable because the true equilibrium for the Al0.25CoFeNi alloy at 500 °C is a mixture of L12 + B2 phases, as revealed by solution thermodynamics modeling. The higher nucleation barrier for the BCC-based ordered B2 phase coupled with the slower kinetics at 500 °C leads to the homogeneous precipitation of L12, while the B2 phase appears to sluggishly grow from grain boundaries acting as heterogeneous nucleation sites.

show abstract