Hf xTa 1-xC-based ceramics exhibit exceptional thermodynamic stability under extreme temperatures. However, their intrinsic brittleness raises significant concerns about their safe service in extreme environments. Her...Hf xTa 1-xC-based ceramics exhibit exceptional thermodynamic stability under extreme temperatures. However, their intrinsic brittleness raises significant concerns about their safe service in extreme environments. Here, we designed and fabricated HfTaC/W_(2) dual-phase ceramics with robust interface bonding through induction plasma spheroidization. During in situ transmission electron microscopy(TEM) mechanical testing, the dual-phase ceramics exhibited plastic deformation with a fracture strength of(7.6 ± 1.2) GPa and a strain of 23.8% ± 0.18% in nanopillar compression, and a fracture strain of 6.2% under tensile loading. The mechanism of plastic deformation in both compression and tensile tests is attributed to the interactions between dislocations and dual-phase interfaces, as well as the dislocation movement inside the W phase. Thus, our work demonstrates the enhanced plasticity of dual-phase HfTaC_(2)/W with a W network embedded in the HfTaC_(2) matrix than singlephase HfTaC_(2) and provides a paradigm for the development of advanced ceramics that combine strength with enhanced ductility for both functional and structural applications.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos.12202330,52501055)the Fundamental Research Funds for the Central Universities and the Innovation Fund of Xidian University (Grant No.YJSJ25017)the Natural Science Basic Research Program of Shaanxi (Grant No.2024JC-YBQN-0459)。
文摘Hf xTa 1-xC-based ceramics exhibit exceptional thermodynamic stability under extreme temperatures. However, their intrinsic brittleness raises significant concerns about their safe service in extreme environments. Here, we designed and fabricated HfTaC/W_(2) dual-phase ceramics with robust interface bonding through induction plasma spheroidization. During in situ transmission electron microscopy(TEM) mechanical testing, the dual-phase ceramics exhibited plastic deformation with a fracture strength of(7.6 ± 1.2) GPa and a strain of 23.8% ± 0.18% in nanopillar compression, and a fracture strain of 6.2% under tensile loading. The mechanism of plastic deformation in both compression and tensile tests is attributed to the interactions between dislocations and dual-phase interfaces, as well as the dislocation movement inside the W phase. Thus, our work demonstrates the enhanced plasticity of dual-phase HfTaC_(2)/W with a W network embedded in the HfTaC_(2) matrix than singlephase HfTaC_(2) and provides a paradigm for the development of advanced ceramics that combine strength with enhanced ductility for both functional and structural applications.
