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TiC/Al–Cu nanocomposites were fabricated in Al–Ti–C powder systems using carbon black, a mixture of C and carbon nanotubes (C + CNTs), and CNTs via an in-situ method involving combustion synthesis and hot pressing. As the carbon source changed from pure carbon black to the C + CNT mixture and pure CNTs, the size of the TiC nanoparticles decreased gradually. The nanocomposites synthesized based on the C + CNT mixture exhibited the most uniform dispersion of TiC nanoparticles. The 30 vol% TiC/Al–Cu nanocomposite prepared from the C + CNT mixture had the best comprehensive mechanical properties (yield strength (411 MPa), compressive strength (712 MPa), fracture strain (17.2%), hardness (206.8 HV), and wear resistance under the experimental conditions due to having the most uniformly dispersed TiC nanoparticles. The wear mechanism was a combination of plastic deformation, abrasion, and adhesion. This method may be a low-cost and convenient means to control the sizes of in-situ TiC nanoparticles and prepare high-performance TiC/Al–Cu nanocomposites. [ABSTRACT FROM AUTHOR]

Hydrogel nanocomposites have been enthusiastically researched as promising candidates with cost-effectiveness and sustainability for solar steam generation and flexible electronics. Based on conductivity derived from salt ions and superior photo-vapor conversion of photothermal nanoparticles, hydrogel nanocomposites hold great potentials for ionotronics and desalination. Here, we report a mechanically robust and multifunctional gel-nacre nanocomposite based on carbon black (CB) nanoparticles strategically embedded in gel-nacre matrix, a physical crosslinked hydrogel reinforced via freeze–thaw and salting out with microphase separation structures. The CB nanoparticles play double roles of acting as nano-crosslinks and providing photothermal conversion capability, coupling gel-nacre matrix with shrinking tendency in saline, contributing to synergistical reinforcement of mechanical performances under saline conditions. The consequent CB@gel-nacre nanocomposite achieves comprehensive mechanical advantages (large strength, high toughness, ductility, and rapid self-recoverability), excellent electrical properties (good conductivity, high sensitivity, fast strain response) as well as photothermal conversion capability. Such versatile gel-nacre nanocomposite provides new opportunities for flexible devices in various scenarios such as ionotronics and desalination. [ABSTRACT FROM AUTHOR]

This paper presents the design, fabrication, and electromagnetic testing of a frequency selective surface (FSS)-based novel hybrid nanocomposite absorber for enhanced electromagnetic absorption. The proposed hybrid absorber consists of an FSS pattern printed over a dielectric substrate backed by aluminum foil, which is integrated together with a customized dielectric nanocomposite sheet. The dielectric sheet comprises the conducting carbon black (CB) nanopowders embedded into the epoxy matrix. The fabricated nanocomposite sheet is first characterized for the effective complex permittivity using the free-space measurement technique, and the measured electromagnetic properties are then used for the design of a hybrid absorber. The proposed hybrid absorber having overall thickness of 2.6 mm shows enhanced −10-dB absorption bandwidth of 3.5 GHz, which is much higher than that of the FSS and CB nanocomposite samples measured individually. The proposed work provides an effective way to combine the absorption properties of FSS with that of a customized dielectric absorber sheet in order to design an efficient hybrid absorber having reduced thickness with enhanced absorption bandwidth for stealth technology and various strategic applications. [ABSTRACT FROM AUTHOR]