Recently aluminum foaming has been of much interest due to its characteristics properties of light weight structure. Metallic foams are highly porous materials which present complex structure of three-dimensional open cells. This aspect causes strong limitations in mass transport due to electro-deposition technology. In this work, the electro-deposition of copper on aluminum open-cell foams substrates was developed, in order to enhance the thermal and mechanical properties of these cellular materials. The mechanical and thermal characterization of the produced samples was lead through compression and conductivity tests. On the basis of the experimental results, analytical models are proposed to predict the quantity and the quality characteristics of the coatin

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a Austenitic stainless steels are characterized by good corrosion resistance in different environments, but their use is limited because of low hardness and poor wear resistance. Conventional thermochemical surface treatments for improving the mechanical strength of steels induce Cr carbide precipitation and thus are detrimental to corrosion resistance. A low-temperature (<470 C) plasma treatment has been developed to overcome this problem and to reduce simultaneously the costs and the time of process. This paper reports the results of a microstructural characterization performed on a series of AISI 316L steel samples treated by plasma-assisted low-temperature carburization in different conditions. Microhardness tests and X-ray diffraction indicated that the best results are achieved by employing a gas mixture with 2% of CH 4 in H 2 . XPS and AES were used to examine the chemical composition of the 20-mm-thick hardened layer. The results revealed that this layer is not homogeneous because a 2-mm-thick overlayer of graphitic nature forms on the surface. Furthermore, only the plasma treatment with 2% of CH 4 guarantees that the whole carbon remains in solid solution, whereas for higher CH 4 amounts in the gas mixture, carbide precipitation takes place.

In this study, laser surface treatment of CFRP made of PPS thermoplastic matrix by means of Q-switched Yb:YAG fiber laser is investigated with the aim to improve CFRP adhesive bonding. Two set of experimental tests were developed. In the first, laser treatments were executed fixing the average power (Pa) and changing: the pulse power, the scanning speed, the hatch distance, and the scanning strategy. These tests were performed to individuate the laser-material interaction mechanisms and the process window. The treated surfaces were investigated using optical microscopy. It was found that the treatment is able to remove the outer layer of the matrix up to the exposure of underlying reinforcement. However, depending to the released energy, incomplete cleaning or excessive damage may occur. Then, the operating window was experimentally determined. In the second experimental tests, single lap shear tests were performed on samples treated under the most promising process conditions, to verify the laser treatment effectiveness. It was found that the laser treatment, compared to the untreated samples, is able to increase the apparent shear strength up to three times