MICROSTRUCTURAL AND MECHANICAL PROPERTIES OF CUCRCOFENI HEA COATINGS ON CU SUBSTRATES: AN ATOMIC-SCALE STUDY

Thanh Nga Trinh; Anh Son Tran; Anh Tuan Nguyen; Anh Tuan Chu

doi:10.65153/kpanw280

Các tác giả

Thanh-Nga Trinh, Anh-Son Tran*, Anh-Tuan Nguyen, Van-Tuan Chu Hung Yen University of Technology and Education Tác giả
Anh Son Tran Hung Yen University of Technology and Education Tác giả
Anh Tuan Nguyen Tác giả
Anh Tuan Chu Tác giả

DOI:

https://doi.org/10.65153/kpanw280

Từ khóa:

CuCrCoFeNi HEA coatings, Cu substrate, coefficient of friction, microstructure, nano scratching

Tóm tắt

High entropy alloys (HEA) are promising candidates for protective coatings owing to their superior mechanical and tribological properties. This study employs molecular dynamics (MD) simulations to examine the nano-scratch behavior of CuCrCoFeNi HEA coatings on crystalline Cu substrates at depths of 5, 10, 15, and 20 Å. The focus is placed on microstructural evolution, deformation mechanisms, and mechanical responses. Results indicate that stacking faults (SF) appear in the Cu substrate at shallow depths (5–15 Å) but shift to concentrate within the coating at 20 Å. This transition, coupled with the FCC to HCP phase transformation, plays a central role in strain hardening, enhancing coating strength, and reducing stress transfer into the substrate. Shear strain distributions confirm that deformation becomes more continuous and localized with increasing depth, while the number of atoms with shear strain > 0.5 grows significantly, peaking at 20 Å. In terms of forces, the normal forces (F_n) always exceed the tangential forces (F_t), with F_n increasing rapidly up to 10 Å and then stabilizing, whereas F_t increases nearly linearly with depth. Correspondingly, the coefficient of friction rises from 0.08 to 0.82. These findings demonstrate the effectiveness of CuCrCoFeNi HEA coatings in absorbing deformation and protecting Cu substrates, providing a theoretical basis for the design of advanced wear-resistant coatings.