As humanity contemplates manned missions to Mars, strategies need to be developed for the design and operation of hospitable environments to safely work in space for years. The supply of spare parts for repair and replacement of lost equipment will be one key need, but in‐space manufacturing remains the only option for a timely supply. With high flexibility in design and the ability to manufacture ready‐to‐use components directly from a computer‐aided model, additive manufacturing (AM) technologies appear extremely attractive. For the manufacturing of metal parts, laser‐beam melting is the most widely used AM process. However, the handling of metal powders in the absence of gravity is one prerequisite for its successful application in space. A gas flow throughout the powder bed is successfully applied to compensate for missing gravitational forces in microgravity experiments. This so‐called gas‐flow‐assisted powder deposition is based on a porous building platform acting as a filter for the fixation of metal particles in a gas flow driven by a pressure difference maintained by a vacuum pump.

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The pore geometry of bone scaffolds has a major impact on their cellular response; for this reason, 3D printing is an attractive technology for bone tissue engineering, as it allows for the full control and design of the porosity. Calcium phosphate materials synthesized from natural sources have recently attracted a certain interest because of their similarity to natural bone, and they were found to show better bioactivity than synthetic compounds. Nevertheless, these materials are very challenging to be processed by 3D printing due to technological issues related to their nanometric size. In this work, bone scaffolds with different pore geometries, with a uniform size or with a size gradient, were fabricated by binder jetting 3D printing using a biphasic calcium phosphate (BCP) nanopowder derived from cuttlebones. To do so, the nanopowder was mixed with a glass-ceramic powder with a larger particle size (45–100 µm) in 1:10 weight proportions. Pure AP40mod scaffolds were also printed. The sintered scaffolds were shown to be composed mainly by hydroxyapatite (HA) and wollastonite, with the amount of HA being larger when the nanopowder was added because BCP transforms into HA during sintering at 1150 °C. The addition of bio-derived powder increases the porosity from 60% to 70%, with this indicating that the nanoparticles slow down the glass-ceramic densification. Human mesenchymal stem cells were seeded on the scaffolds to test the bioactivity in vitro. The cells’ number and metabolic activity were analyzed after 3, 5 and 10 days of culturing. The cellular behavior was found to be very similar for samples with different pore geometries and compositions. However, while the cell number was constantly increasing, the metabolic activity on the scaffolds with gradient pores and cuttlebone-derived powder decreased over time, which might be a sign of cell differentiation. Generally, all scaffolds promoted fast cell adhesion and proliferation, which were found to penetrate and colonize the 3D porous structure.

Radio frequency identification (RFID) applications are becoming more and more important in logistics, especially for the purpose of tracking and managing items. Real time tracking of medical instruments during a surgical operation belongs to the state-of-the-art applications of this technology. The metallic environment in the operating room represents a big challenge, hampering the readability of the RFID tag. Currently, transponders are joined to metal instruments by bonding or clamping them inside a polymer shell, containing as little metal as possible. Assembling the tags is a time consuming process, which changes the usual shape of the instrument. It also represents a point of failure because of the possibility of losing the tag during the instrument's life cycle. Selective laser melting (SLM) offers a way to integrate the entire RFID tag in a metallic instrument while keeping the original shape. Instrument manufacturing by SLM allows small wall thicknesses and a reduced temperature impact on the RFID tag during the building process. The production of trial components from IN718 nickel alloy is reported

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