Computational Analysis of Deformation Mechanisms in Cold-Sprayed Cantor Alloy

High-entropy alloys (HEAs), particularly the Cantor alloy (CoCrFeMnNi), exhibit exceptional mechanical properties, making them promising for advanced applications. However, their deformation mechanisms in cold spray deposition are still not fully understood. This study investigates the deformation mechanisms of cold-sprayed Cantor alloy at 950°C and 4.9 MPa. A computational fluid dynamics (CFD) model was implemented to gain further insights into these mechanisms and predict particle velocity and temperature upon impact. A finite element method (FEM) model and molecular dynamics (MD) simulations were conducted to study thermal softening, and analyze generalized stacking fault energy (GSFE), respectively.
The critical resolved shear stress (CRSS) for slip and twinning was determined using different models: the Kibey equation for calculating twinning stress in single-crystal Cantor alloy, the Hall-Petch equation for polycrystalline twinning stress estimation, and the Peierls-Nabarro (P-N) model for slip stress calculation. Electron backscatter diffraction (EBSD) and high-resolution transmission electron microscopy (HRTEM) confirmed that slip dominates near the interface, while twinning occurs farther from the interface due to the higher strain-hardening rate of slip.

Keywords: CoCrFeMnNi; Molecular dynamic; Critical resolved shear stress; Twinning; slip