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We describe a methodology to obtain three-dimensional models of engineered surfaces using scanning electron microscopy and multi-view photogrammetry (3DSEM). For the reconstruction of the 3D models of the surfaces we used freeware available in the cloud. The method was applied to study the surface roughness of metallic samples patterned with parallel grooves by means of laser. The results are compared with measurements obtained using stylus profilometry (PR) and SEM stereo-photogrammetry (SP). The application of 3DSEM is more time demanding than PR or SP, but it provides a more accurate representation of the surfaces. The results obtained with the three techniques are compared by investigating the influence of sampling step on roughness parameters.

DMLS (Direct Metal Laser Sintering) Additive manufacturing allows building topological optimized geometries with good mechanical properties and low weight. These features are appropriated for the aeronautical industry because the reduction of weight involves saving costs per trip. However, the manufacturing cost using SLM (Selective Laser Melting) or DMLS, is also high since titanium alloys powder is expensive. Therefore, this work aims to explore the possibility of using 15-5PH stainless steel powder to balance the mechanical properties, weight and cost of the part.

MnOx–CeO2 and Pt(2%)/MnOx–CeO2 catalysts were prepared and investigated in the catalytic wet oxidation (CWO) of phenol. The reaction was carried out in a high-pressure autoclave reactor operating at 140 °C and oxygen partial pressure of 2 MPa. The effect of a reduction pre-treatment at 350 °C on the catalytic performance of both, the platinum catalyst and the bare oxide was studied. Higher activities were found for the reduced catalysts, independently of the presence or absence of Pt. Formation of carbonaceous deposits on the catalytic surface and leaching of manganese was confirmed as the two major deactivation mechanisms occurring in CWO of phenol. The amounts of deposits formed and manganese leached were higher in the case of reduced samples. Different techniques (XRD, HREM, HAADF, EDS, ICP) were used to characterise the chemical and structural changes experimented by the catalysts during reaction. The behaviour of reduced catalysts was found to be associated to the presence of MnO. The formation of this manganese oxide phase during the reduction pre-treatment significantly influenced the catalytic performance and stability of the catalysts under operation conditions.