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Diamond/aluminum composites have the advantages of high thermal conductivity and low density, making them ideal cooling materials for aerospace electronic devices. However, there is a lack of comprehensive research on the factors influencing the thermal conductivity of diamond/aluminum composites, as well as their reliability. In view of the above problems, spark plasma sintering method was utilized to prepare diamond/aluminum composites with a thermal conductivity of 462 W/(m·K). It considered the effects of sintering temperature, holding time, and diamond particle size combination. Additionally, the heat spreader reliability of this diamond/aluminum composite in high and low temperature and vibration environment was studied. The results demonstrated that the diamond/aluminum composite effectively reduced the heat source temperature by 13 °C compared to aluminum alloy when subjected to a heat flux of 70 W/cm². Furthermore, diamond/aluminum composites can maintain stable physical properties and structural reliability in the high and low temperature and vibration environment, effectively exerting their heat dissipation capacity. Overall, diamond/aluminum composites can be presented as a reliable solution for heat dissipation in aerospace electronic devices. [ABSTRACT FROM AUTHOR]

Personal radiative cooling fabrics are a promising zero‐energy solution for creating a cool and comfortable microclimate for outdoor crowds. Despite significant progress, achieving efficient radiative cooling under some extreme situations, such as thermal shock and intensive physical activity, remains a challenge. Herein, a bioinspired metafabric with a dual‐gradient Janus design is reported for personal radiative and evaporative cooling. The hierarchical fiber structure allows for an excellent solar reflectance of 99.4% and mid‐infrared emittance of 0.94, inducing a skin temperature drop of 17.8 °C under intense sunlight. Mesoporous silica nanoparticles fixed in the fibrous network can store evaporative cooling capacity by atmospheric moisture‐absorption in the mild and humid nighttime and release such cooling capacity by moisture‐desorption in the hot daytime, providing an additional skin temperature drop of 2.5 °C. Dual‐gradient Janus design endows the metafabric with an outstanding sweat‐wicking effect and high‐performance sweat evaporative cooling capacity. In the steady‐state evaporation tests, a maximum sweat consumption of only 0.5 ml h−1 can cool the skin to a comfortable temperature, preventing harmful excessive sweating. Additionally, the bioinspired metafabric also possesses favorable wearability and color expansibility. Given these first‐rate features, the bioinspired metafabric will pave the way for the development of advanced functional fabrics. [ABSTRACT FROM AUTHOR]

As a temperature self-regulating heater material, the doped BaTiO3 exhibits an attractive application perspective in the thermal management of electrical devices. However, the high Curie temperature does not meet the requirement in the thermal control application. In this work, (Ba0.997−xCe0.003Srx)(TiNb0.002)O3 (x=0.2, 0.3, 0.35, abbreviated as BCSTNs) ceramics were prepared by the solid-state reaction method. The purpose of doping different content of strontium is to shift the Curie temperature of BaTiO3-based ceramic to the ambient temperature region, maintaining excellent PTC effect and low room-temperature resistivity by codoped cation ions in Ba- and Ti-site. The influences of sintering temperature and soak time on the microstructure as well as electrical properties of BCSTNs ceramics have been studied. The X-ray diffraction reveals that the composition with x=0.35 exhibits the coexistence of tetragonal and cubic lattice symmetries, confirmed by the Rietveld structure refinement. The dense microstructure with average grain sizes 0.84–7.87 μm was observed for BCSTN ceramics. Temperature-resistivity measurements demonstrate that TC of the ceramics with x=0.35 shifted to the room temperature region. Additionally, the BCSTN ceramic with heavy doping Sr exhibits relative low room-temperature resistivity and the resistance jump greater than 2.0 orders of magnitude. [ABSTRACT FROM AUTHOR]