The multifunctional superhydrophobic surfaces incorporated with Fe3O4 exhibit excellent anti-icing and active deicing properties.

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Hydroxyapatite (HA) bioceramic scaffolds were fabricated by using digital light processing (DLP) based additive manufacturing. Key issues on the HA bioceramic scaffolds, including dispersion, DLP fabrication, sintering, mechanical properties, and biocompatibility were discussed in detail. Firstly, the effects of dispersant dosage, solid loading, and sintering temperature were studied. The optimal dispersant dosage, solid loading, and sintering temperature were 2 wt%, 50 vol%, and 1250 ℃, respectively. Then, the mechanical properties and biocompatibility of the HA bioceramic scaffolds were investigated. The DLP-prepared porous HA bioceramic scaffold was found to exhibit excellent mechanical properties and degradation behavior. From this study, DLP technique shows good potential for manufacturing HA bioceramic scaffolds.

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Silicon carbide (SiC) ceramic and related materials are widely used in various military and engineering fields. The emergence of additive manufacturing (AM) technologies provides a new approach for the fabrication of SiC ceramic products. This article systematically reviews the additive manufacturing technologies of SiC ceramic developed in recent years, including Indirect Additive Manufacturing (Indirect AM) and Direct Additive Manufacturing (Direct AM) technologies. This review also summarizes the key scientific and technological challenges for the additive manufacturing of SiC ceramic, and also forecasts its possible future opportunities. This paper aims to provide a helpful guidance for the additive manufacturing of SiC ceramic and other structural ceramics.

Eliminating the leakage current is one of the most important issues for transformerless three phase photovoltaic (PV) systems. In this paper, the leakage current elimination of a three-phase four-leg PV inverter is investigated. With the common mode loop model established, the generation mechanism of the leakage current is clearly identified. Different typical carrier-based modulation methods and their corresponding common mode voltages are discussed. A new modulation strategy with Boolean logic function is proposed to achieve the constant common mode voltage for the leakage current reduction. Finally the different modulation methods are implemented and tested on the TMS320F28335 DSP +XC3S400 FPGA digital control platform. The experimental results verify the effectiveness of the proposed solution.Index Terms-Transformerless photovoltaic system, three-phase four-leg inverter, pulse width modulation, leakage current

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In this work, silicon nitride ceramic components with simple cuboid and complex honeycomb and lattice structures from preceramic polymers were fabricated by using digital light processing (DLP) based additive manufacturing and pyrolysis. The photosensitive precursor for DLP based additive manufacturing was prepared by mixing high ceramic yield polysilazane with commercial acrylic resin and photoinitiator. The material formulation and the structure of the green body were characterized by using FTIR. Si3N4 ceramic cuboid, 2D‐structured Si3N4 ceramic honeycomb, and 2D‐structured Si3N4 ceramic lattice with high precision were fabricated. The DLP‐prepared specimens were pyrolyzed at different temperatures, and the crystalline phases after pyrolysis were analyzed by using XRD. The optimal pyrolysis temperature was found to be 1400°C.microstructures were characterized by using SEM. The compressive behavior of the complex‐shaped Si3N4 ceramic structures was measured and discussed in detail.