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This paper aims to examine customized NiTi jewels with functional properties fabricated through four-dimensional (4D)-printing.

Two opened rings are fabricated through selective laser melting starting from 55.2Ni-Ti (wt.%) micrometric powder. After the additive process the two rings present the one-way shape memory effect (OWSME). A specific training is accomplished on one of the two printed rings to promote the two-way shape memory effect (TWSME). Both the samples, namely, the rings, respectively, presenting the OWSME and TWSME property, follow a series of post-processing routes to improve the surface finish. Furthermore, a thermal treatment at high temperature is used to create a thin colored oxide layer on the sample surface.

Results show that the change of shape owing to the OWSME and TWSME properties allows the customized 4D-printed rings to be adaptable to environmental changes such as load and temperature variations. This adaptability improves comfort and fit of the jewels.

To the best of the authors’ knowledge, in this work, first cases of additively manufactured NiTi jewels are reported to propose innovative solutions in the design and processing industry of jewels.

This paper aims to investigate the microstructural anisotropy of Ti-6Al-4V samples fabricated by selective laser melting.

Specimens are fabricated through a Renishaw AM400 selective laser melting machine. Three microstructures (as-built, 850°C annealed and 1,050°C annealed) and two building orientations, parallel (PA) and perpendicular (PE) to the building platform, are considered. Starting from in-depth microscopic observations and comprehensive electron backscattered diffraction imaging, the study addresses non-conventional techniques such as internal friction and electrical resistivity measurements to assess the anisotropy of the fabricated parts.

Microscope observations highlight a fine texture with columnar grains parallel to the building direction in the as-built and 850°C annealed samples. Besides, coarse grains characterized the 1,050°C annealed specimens. Internal friction measurements pointed out the presence of internal stress while storage modulus analyses appear sensitive to texture. Electrical resistivity is resulted to be dependent on grain orientation.

The work uses some novel characterization techniques to study the anisotropy and internal stresses of Ti-6Al-4V samples processed by selective laser melting. Mechanical spectroscopy results suitable in this kind of study, as it mimics the operating conditions of the material.