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ZrO2‐whisker‐reinforced Ti(C,N)‐based cermets were designed and prepared via a vacuum hot‐pressing process. The ZrO2 whisker characteristics and the phase, microstructure and mechanical properties of the cermets were investigated, and the relevant toughening mechanisms were examined. The results indicate that the ZrO2 whiskers retain their morphology and significantly improve the mechanical properties of the cermets. The relative density and hardness decreased slightly with increasing ZrO2 whisker content. At a whisker content of 7.5 wt.%, the fracture toughness and flexural strength reached their maximum values of 7.825 MPa·m1/2 and 1094 MPa, respectively. This enhancement in the mechanical properties is due to stronger bonding between the interfaces through dimples, tearing ridges and whisker pull‐out, in addition to the inhibition of crack propagation via crack deflection, crack branching and crack bridging. [ABSTRACT FROM AUTHOR]

Simultaneously tuning light absorption wavelength and absorbance is a critical challenge in photoelectric detection, mimic of photosynthesis, and simulation of photoreceptors in some animals' retinas. Here, highly ordered hexagonal nanostructured Si arrays are fabricated using monolayer colloid crystal templates. A quantitative relationship between geometric size and light absorption is unveiled in the Si arrays, namely double‐quarter‐wavelength resonance (DQWR). Based on the DQWR model, the absorption wavelength can be readily tuned from 200 to 2400 nm, and the absorbance can be enhanced from ≈80% to above 99% in the full spectrum. Due to the hemisphere‐shell structural feature of the Si arrays, excellent omnidirectional antireflective performance can also be realized. Most importantly, the outstanding antireflection performance of the nanostructures is independent of the substrate. The results not only have important implications for understanding the antireflective mechanism of the nanostructured arrays, but also endow the approach promising in diverse applications, including biomimicry, antireflective film, infrared imagery, and other optoelectronic devices. [ABSTRACT FROM AUTHOR]