@article{Wang2026, 
author = {Kaihang Wang and Yan Zhang and Guanshui Ma and Yuxi Xu and Zhenyu Wang and Aiying Wang},
title = {Exceptional mechanical properties of (Ti1−xZrx)2AlC MAX phase coatings with amorphous-nanocrystalline oxidation layers},
year = {2026},
journal = {Journal of Advanced Ceramics},
volume = {15},
number = {1},
pages = {9221201},
keywords = {solid solution, gradient structure, MAX phase coating, amorphous-nanocrystalline, hardness–toughness},
url = {https://www.sciopen.com/article/10.26599/JAC.2025.9221201},
doi = {10.26599/JAC.2025.9221201},
abstract = {The brittleness of hard ceramic materials poses a significant challenge to their practical application because of the trade-off between hardness and toughness. Here, we propose a hierarchical structure strategy that utilizes alloying and vacuum oxidation to fabricate MAX phase coatings with an amorphous-nanocrystalline oxidation layer on the surface. Hierarchical (Ti1−xZrx)2AlC coatings (x = 0.05–0.18) were prepared via magnetron sputtering followed by vacuum annealing, and the hardness and fracture toughness increased simultaneously with increasing Zr content. A maximum hardness of 19.4 GPa and fracture toughness of 4.1 MPa·m1/2 were achieved in the (Ti0.82Zr0.18)2AlC coating, significantly surpassing previously reported MAX phase coatings. The enhanced hardness primarily originated from the formation of solid solutions of Zr at the M-site and second phase Zr3Al2, whereas the exceptional toughness was attributed to the amorphous-nanocrystalline structure in the surface oxidation layer and the gradient structure of the coatings. These findings provide a pioneering approach based on alloying and oxidation for developing hard yet tough MAX phase coatings and other ceramic materials.}
}