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PMMA and PMMA/10 wt% nano-AlO fibre mats were produced by means of electrospinning and used as reinforcing phase of poly(ε-caprolactone) matrix. The composite films were fabricated by means of film-stacking technique. SEM observations showed good wettability of PMMA-based fibres by the PCL matrix, confirming that a strong interface was formed. The AlO nanoparticles were well-distributed along the polymeric fibres. The introduction of PMMA fibres as a reinforcement led to a clear benefit in terms of the mechanical strength (11.5 ± 0.5 MPa), the value for neat PCL being 8.2 ± 2.2 MPa. The tensile strength was further increased when the fibres were loaded with nano-AlO (14.4 ± 0.6 MPa) due to both the presence of the ceramic filler and the smaller diameter of the composite fibres. A less marked improvement was instead found on stiffness. [ABSTRACT FROM AUTHOR]

The effect of mix composition on foam morphology has been examined by image analysis carried out on metallographic sections of Al foams prepared by powder metallurgy. Two sets of samples have been prepared by using SiC particles with mean sizes of 37 and 60 µm. Each set consists of 16 groups of samples with different amounts of TiH2 (0.1, 0.2, 0.4, and 0.6 wt%) and SiC (0.8, 2.8, 6, and 9 wt%). The distribution of SiC particles on the internal walls of the bubbles has been investigated by scanning electron microscopy observations, which evidenced also the presence of particles of another phase, identified as Ti3Al by energy dispersion spectroscopy. Some tests, performed without SiC particles, showed that the Al foaming occurs also under these conditions, however foams exhibit few bubbles of very large size and irregular shape. Experimental data have been used for training two multi-layer feedforward artificial neural networks. The models represent useful tools for predicting morphologic features of foams for any given mix composition in the training range. [ABSTRACT FROM AUTHOR]