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Casting process simulation is nowadays established as a strategic tool in process optimisation to improve product quality. However, sometimes the required three-dimensional mathematical model of the casting is not available, because the original drawings are not-up-to date and parts are subjected to design changes. In these cases, reverse engineering (RE) is the most suitable method to reconstruct the geometrical model of the casting. In this paper, a RE-based procedure is proposed to obtain the three-dimensional CAD model of a casting from its physical equipment. The proposed procedure involves four phases: pre-digitising, digitising of equipment parts, surface reconstruction, and three-dimensional CAD modelling. An aeronautical part fabricated by sand casting is selected as case study to verify the feasibility of this approach. Outcomes prove that the RE methodology is adequate to virtually reconstruct the geometry of each single part of the equipment as well as the whole geometry of the assembled mould. [ABSTRACT FROM AUTHOR]

New brake-pad materials are inhomogeneous compounds with a variety of metallic and ceramic phases, whose interaction with the tool during the grinding operation is not fully understood. Yet, ground surface quality strongly influences the bedding-in phase. This research surveys how grinding operation affects the pad surface. The purpose is pursued by adopting an investigation protocol merging macroscopic outcomes with the study of chip-removal mechanisms and of the ground surface morphology in the microscale. A specific set of grinding tests is carried out on the friction material under different kinematic conditions. Macroscopic indicators of the process performances are measured and modeled. Al a closer look, the ground surface shows a complex morphology that cannot be completely described by roughness valuer, but depends on how the various phases are distributed in the material and how they are affected by the tool during abrasion. A multiscale inspection procedure is proposed to assess the performances of a machining operation on complex materials, where the descriptive power of standard technological tests becomes inadeauate. [ABSTRACT FROM AUTHOR]

The article presents the study on the human remains discovered at the Giants Tomb in Pedrera, Monastir, Italy as in late 2009-mid-2010. The remains were restored and cleaned before they were analyzed. The age, corresponding pathologies, and estimated statures of the remains were examined through morfological examinations.

Metal additive manufacturing is a major concern for advanced manufacturing industries thanks to its ability to manufacture complex-shaped parts in materials that are difficult to machine using conventional methods. Nowadays, it is increasingly being used in the industrial manufacturing of titanium-alloy components for aerospace and medical industries; however, the main weakness of structural parts is the fatigue life, which is affected by surface quality, meaning the micro-cracking of small surface defects induced by the manufacturing process. Laser finishing and Abrasive Fluidized Bed are proposed by the authors since they represent cost-effective and environment-friendly alternatives for automated surface finishing. A comparison between these two finishing technologies was established and discussed. Experimental tests investigated both mechanical properties and fatigue performances. The tests also focused on understanding the basic mechanisms involved in fatigue failures of machined Ti-6Al-4V components fabricated via Electron Beam Melting and the effects of operational parameters. X-ray tomography was used to evaluate the internal porosity to better explain the fatigue behaviour. The results demonstrated the capability of Laser finishing and Abrasive Fluidized Beds to improve failure performances. Life Cycle Analysis was additionally performed to verify the effectiveness of the proposed technologies in terms of environmental impact and resource consumption.

The literature on Orthorexia Nervosa (ON) rapidly grew in recent years, highlighting the perverse and paradoxical aspects of healthy eating. In this review, authors examine the different meanings of ON, the proposals of diagnostic criteria and evaluation tools, and the most promising research tracks that, if developed, will allow to fully understand the nature of ON, and therefore identify strategy for secondary and primary prevention.

Additive manufacturing allows for a great degree of design freedom and is rapidly becoming a mainstream manufacturing process. However, as in all manufacturing processes, it has its limitations and specificities. Equipping engineers with this knowledge allows for a higher degree of optimization, extracting the most out of this technology. Therefore, a specific part design was devised and created via L-PBF (Laser Powder Bed Fusion) using AlSi10Mg powder. Certain parameters were varied to identify the influence on material density, hardness, roughness, residual stress and microstructures. It was found that on heat treated parts laser pattern strategy is one of the most influential aspects, showing that chessboard and stripes 67° improved outcome; average R a roughness varied between 8-12 µm, residual stress was higher on vertical surfaces than horizontal surfaces, with the combination of support structures and stripes 67° strategies generating the lowest residual stress (205 MPa on a lateral/vertical face), hardness was non-orientation dependent and larger on samples with chessboard fabrication strategies, while microstructures were composed of α-Al dendrites surrounded by Si particles. The distribution and grain size of the microstructure is dependent on location regarding melt pool and HAZ area. Furthermore, Al-Mg oxides were encountered on the surface, along with pores generating from lack of fusion.

Directed Energy Deposition (DED) is one of the most promising additive manufacturing technologies for the production of large metal components and because of the possibility it offers of adding material to an existing part. Nevertheless, DED is considered premature for industrial production, because the identification of the process parameters may be a very complex task. An original hybrid analytic-numerical model, related to the physics of laser powder DED, is presented in this work in order to evaluate easily and quickly the effects of different sets of process parameters on track deposition outcomes. In the proposed model, the volume of the deposited material is modeled as a function of process parameters using a synergistic interaction between regression-based analytic models and a novel element activation strategy. The model is implemented in a Finite Element (FE) software, and the forecasting capability is assessed by comparing the numerical results with experimental data from the literature. The predicted results show a reasonable correlation with the experimental dimensions of the melt pool and demonstrate that the proposed model may be used for prediction purposes, if a specific set of process parameters that guarantees adequate adhesion of the deposited track to the substrate is introduced.

In this paper, a characterization of an AlSiMg alloy processed by direct metal laser sintering (DMLS) is presented, from the analysis of the starting powders, in terms of size, morphology and chemical composition, through to the evaluation of mechanical and microstructural properties of specimens built along different orientations parallel and perpendicular to the powder deposition plane. With respect to a similar aluminum alloy as-fabricated, a higher yield strength of about 40% due to the very fine microstructure, closely related to the mechanisms involved in this additive process is observed.

An innovative benchmark representing a dental arch with classic features corresponding to different kinds of prepared teeth is proposed. Dental anatomy and general rules for tooth preparation are taken into account. This benchmark includes tooth orientation and provides oblique surfaces similar to those of real prepared teeth. The benchmark is produced by additive manufacturing (AM) and subjected to digitization by a dental three-dimensional scanner. The evaluation procedure proves that the scan data can be used as reference model for crown restorations design. Therefore this benchmark is at the basis for comparative studies about different CAD/CAM and AM techniques for dental crowns., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The clinical usefullness of the CPK MB test (spectophotometric method) was evaluated on 139 patients admitted to a Cardiovascular Diseases Department with a diagnosis of suspected myocardial infarction. Serial determinations of serum MB isoenzyme creatine kinase, total creatine kinase, lacate dehydrogenase and hydrossibutirrate dehydrogenase were made at 1st, 2th, 3th, 4th, 5th, 6th, 7th day. Incidence of CPK MB false positive and false negative data were also determined and correlated with the electrocardiogram pattern and serum levels of other standard enzymes. Results indicate that the CPK MB kinetic test is highly specific (94%) and promptly available in the early diagnosis of acute myocardial infarction.

The behaviour of serum haemopexin was studied in patients with hyperhaemolysis after ingestion of fava beans. The linear increase in this substance after a crisis is particularly emphasized. This finding is of special importance for G-6-PD subjects with various haematological disorders.