Additive manufacturing is a promising and emerging technology that can transform the global manufacturing and logistics by cutting costs and times of production. Localized corrosion resistance properties of 0°, 45°, and 90° build-up orientations of 17-4 PH as-sintered samples, manufactured by means of Bound Metal Deposition (BMD), have been investigated by electrochemical and morphological investigations. The cyclic potentiodynamic polarization curves and the open circuit potential monitoring, together with potential drop analysis, revealed that the BMD localized corrosion resistance properties were lowered if compared to a wrought 17-4 PH: a characteristic anodic behavior and many drops in potential were recorded for BMD, whilst the wrought specimens presented a typical passive behavior with pitting corrosion. Morphological investigations by scanning electron microscopy and energy-dispersive X-ray analysis revealed the presence of porosities and defects, especially for the 90° build-up orientation, and inclusions of SiO2. The 45° build-up orientation showed the best corrosion resistance properties among all the BMD specimens, even though defects and porosities were observed, suggesting that their morphology and geometry influenced the overall corrosion behavior.

Scanning microwave microscopy (SMM) is a novel metrological tool that advances the quantitative, nanometric, high-frequency, electrical characterization of a broad range of materials of technological importance. In this work, we report an inverted near-field scanning microwave microscopy (iSMM) investigation of a graphene oxide-based epoxy nanocomposite material at a nanoscopic level. The high-resolution spatial mapping of local conductance provides a quantitative analysis of the sample’s electrical properties. In particular, the electrical conductivity in the order of ∼10−1 S/m as well as the mapping of the dielectric constant with a value of ∼4.7 ± 0.2 are reported and validated by the full-wave electromagnetic modeling of the tip–sample interaction.

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Phase change materials (PCMs) with a solid-solid phase transition are receiving increasing attention as promising materials for thermal energy storage (TES) systems. Unlike the more well-known and widespread solid-liquid PCMs, they generally have negligible volume change during phase transition, no contamination, and long cyclic life. Among the most studied solid-solid PCMs, a group of organic materials known as plastic crystals and their mixtures seem to show energy storage properties suitable for solar thermal systems at low-medium temperatures (80-150℃). In this study, to deeply analyze their suitability for these applications, the thermophysical properties and thermal stability of two promising plastic crystals, pentaerythritol (PE) and pentaglycerine (PG), and their mixture are reviewed. The phase transition properties of these two pure substances were also assessed in this study through differential scanning calorimetry (DSC). The experimental measurements showed good agreement with the data collected from literature. The analysis showed that various properties and characteristics of these materials should be further investigated since a limited number of studies related to their properties is available. However, if their drawbacks are adequately addressed, the studied plastic crystals seem suitable for TES applications.