@article{Liu2025, 
author = {Shucheng Liu and Yue Pan and Bingtao Feng and Baoyin Xu and Kuo Hu and Xiaojun Xiang and Leiming Fang and Xiaohong Yuan and Qiang Tao and Pinwen Zhu and Zhaodong Liu and Hu Tang and Bingbing Liu},
title = {Toughening of silicon nitride ceramics through stress-induced phase transformation},
year = {2025},
journal = {Journal of Advanced Ceramics},
volume = {14},
number = {8},
pages = {9221125},
keywords = {silicon nitride, transformation toughening, high-pressure and high-temperature (HPHT), interface engineering},
url = {https://www.sciopen.com/article/10.26599/JAC.2025.9221125},
doi = {10.26599/JAC.2025.9221125},
abstract = {Ceramics, particularly covalently bonded ceramics, exhibit intrinsic brittleness resulting from the strong directional nature of their chemical bonds, significantly limiting their applications. Despite extensive research, effective strategies for substantially enhancing the toughness of covalently bonded ceramics without compromising their exceptional properties have remained elusive. Here, we present a breakthrough in the transformation toughening of dual-phase α/β-Si3N4 ceramics, driven by stress-induced β-to-α phase transformation. Through a nucleation and growth method, we successfully synthesized dense, dual-phase α/β-Si3N4 ceramics with coherent interfaces under high-pressure and high-temperature (HPHT) conditions. The dual-phase α/β-Si3N4 ceramics demonstrate exceptional toughness, reaching 7.30 MPa·m1/2, which is more than double that of β-phase silicon nitride. The significant toughening is attributed to localized plastic deformation caused by stress-induced phase transformation, which hinders crack propagation. This represents the demonstration of stress-induced transformation toughening in covalently bonded ceramics, highlighting the transformative potential of interface engineering for enhancing the toughness of brittle ceramics.}
}