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The Powder Bed Fusion-Laser Beam/Metals (PBF-LB/M) is a promising additive manufacturing process that can be used to directly produce functional components with a complex shape for a wide variety of applications. However, the layer-by-layer scanning and high cooling rates result in a high thermal gradient and thus, in thermally induced stresses. The stresses developed during the additive process could lead to undesirable cracking and delamination phenomena that can seriously affect the performance of the final component. The alloy composition can exacerbate crack and delamination formation, however, the need to expand the portfolio of high-strength materials processable for PBF-LB/M makes the resolution of these undesirable phenomena a primary challenge in the additive manufacturing field. This works aims to systematically investigate some strategies to make processable non-standard compositions. As no standard compositions, the promising pre-alloyed AlSi10Cu8Mg composition was chosen for the present work. Based on the results obtained from a condition of severe delamination, the synergetic use of appropriate process parameters and support structures can lead to crack-free and fully dense specimens also when platform heating is not allowed. The developed approach could also be applied to adapt other cracking-sensitive alloys for PBF-LB/M production.

In this study bioactive and bioresorbable porous scaffolds for bone tissue regeneration, based on poly(3-hydroxybutyrate) (PHB), are presented. The porous structure is obtained by thermally induced phase separation (TIPS) technique, whereas the osteoinductivity and osteoconductivity are enhanced through the incorporation of hydroxyapatite (HA). The HA particles are generated in PHB using an innovative filler in situ synthesis, and the properties of the composite scaffolds are then compared to scaffolds obtained by conventional mechanical dispersion of ex situ synthesized HA particles. The in situ synthesis leads to composite materials with improved porosity, even at high filler content, without any degradation of the polymeric matrix as confirmed by GPC and DSC measurements. On the contrary, the samples prepared by ex situ method show a suppressed porosity by increasing the inorganic filler content, therefore limiting the amount of HA that can be loaded in PHB and the resulting bioactivity. The possibility to use PHB/HA porous composites as scaffolds for bone tissue regeneration, is assessed by preliminary cell viability in vitro studies. In particular, it is observed that the composites are fully cytocompatible and able to sustain MC3T3-E1 mouse pre-osteoblast cells adhesion and proliferation. Investigations on cell morphology reveal, for all PHB/HA scaffolds, the presence of differentiated cells with a predominance of osteocyte-like morphology, which are not observed for neat PHB scaffolds. Moreover, the MC3T3-E1 cells differentiation towards osteoblastic phenotype is further supported by the evaluation of the early osteogenic markers. In particular, samples loaded with HA in situ synthesized showed the highest ALP production and typical morphology of the terminal differentiation stages of osteoblasts., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Recently, there has been a rise in the interest in nanotechnology due to its enormous potential for the development of new products and applications with higher performance and new functionalities. However, while nanotechnology might revolutionize a number of industrial and consumer sectors, there are uncertainties and knowledge gaps regarding toxicological effects of this emerging science. The goal of this research concerns the implementation into Life Cycle Assessment (LCA) of preliminary frameworks developed to evaluate human toxicity and exposure factors related to the potential nanoparticle releases that could occur during the life cycle steps of a functionalized building material. The present LCA case study examines the ecodesign of nanoTiO 2 functionalized porcelain stoneware tile production. The aim of this investigation is to manufacture new eco-friendly products in order to protect human health and ecosystem quality and to offer the market, materials with higher technological properties obtained by the addition of specific nanomaterials., (Copyright © 2016 Elsevier B.V. All rights reserved.)

In this work the screening results of the scientific activity conducted on laboratory scale to valorise chromium(III) contained in the galvanic sludge as chromium precursor for ceramic pigments are reported. The valorisation of this waste as a secondary raw material (SRM) is obtained by achievement of thermal and chemical stable crystal structures able to color ceramic material. Two different pigments pink CaCr(0.04)Sn(0.97)SiO(5) and green Ca(3)Cr(2)(SiO(4))(3) were synthesized by solid-state reactions using dried Cr sludge as chromium oxide precursor. The obtained pigments were characterized by X-ray diffraction and SEM analysis. Furthermore the color developed in a suitable ceramic glaze was investigated in comparison with the color developed by the pigments prepared from pure Cr(2)O(3). The characterization carried out corroborates the thermal and chemical stability of the synthesized pigments and, especially for the Cr-Sn pink pigment, the powders develop an intense color that is very similar to the color developed by the pigments obtained starting from pure Cr(2)O(3).