To ensure the financial viability of powder-based additive manufacturing technologies, the recycling of powders is common practice. This paper shows the lifecycle of metal powder in additive manufacturing, investigating powder manufacture, powder usage, mechanisms of powder degradation and the usage of end-of-life powder. Degradation of powders resulting from repeated reuses was found to be a widespread problem; components produced from heavily reused powders are typically of a lower quality, eventually rendering the powder unusable in additive manufacturing. Powder degradation was found to be dependent on many variables, preventing the identification of a definitive end-of-life point for powders. The most accurate method of determining powder quality was found to be the production and analysis of components using these powders. Uses for degraded powder had not been previously identified in literature, warranting the investigation of potential solutions to prevent powder waste. Amongst other waste-reducing solutions, plasma spheroidisation was identified as a promising method to avoid powder disposal for approximately 12.5% of produced powders, creating particles similar to virgin powder from end-of-life powder. Returning end-of-life powders to the supplier for upcycling may be the only financially viable solution to reduce waste within the industry. The compilation of research within this paper aims to enable users of additive manufacturing to conduct further research and development into powder upcycling.

Traditional metal filters are manufactured from perforated plate which forms the filter support to withstand operational pressures and one or more layers of woven wire mesh to form the filter portion at the required level of filtration. The design freedoms and capabilities of additive manufacturing (AM) technology provide the opportunity to design novel filter media with integrated support and filter portions that have defined aperture size and strand diameter. Maximizing the open area of a filter increases filtration efficiency. AM integrated filter support and filter portion designs were optimized and the resultant filter media discussed have the potential to decrease the end users' pumping energy requirements and so reduce energy costs and the inherent carbon footprint.

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Wired mesh packings have seen increasing applications to multiphase processes in recent years. Despite the high surface area, open structure and thermal and chemical resistance, wired mesh packings have a complex geometry which hinders some chemical applications, including changes of surface properties through application of a uniformly adhesive coating.In this work, the sol-gel deposition method of alumina coating ceramics was investigated for the first time on stainless steel wired mesh by using Dixon rings as example. The kinetics of deposition during the hydrolysis and polycondensation was followed for a range of initial composition of the coating such as the ratios of Al2O3 to water, acid content, 2 polyethyleneimine binder content and the number of deposition cycles. Well-adhered alumina with a thickness up to 20 µm was successfully deposited. The molar ratios of acid to alumina and alumina to water of 0.25 and 0.01, respectively, 48 h of the aging time, 96 h of the mixing time and 2.1 g/L of polyethyleneimine binder formed a free of cracks coating of controlled thickness alumina on the Dixon rings.