2013

The paper presents the tensile behavior of sintered steels developed through a new process called gascarbusintering (GCS), consisting of carburizing in gas (CH4) of a set of iron based powder compacts followed by sintering. The influence of compaction pressure and dwell time at the carburizing temperature on the tensile properties of steels processed by GCS is investigated.

The paper is focused on the processing of aluminum alloy chips using powder metallurgy. Chips obtained from recycled AlSi5Cu2 alloy were ball milled with the addition of silicon carbide powder with an average size of 2um. Mechanical alloying process was employed to obtain homogeneous composite powder. The effect of processing time (0 - 40h) on the homogeneity of the system was evaluated, as well as a detailed study of the microstructure of AlSi5Cu2 aluminum chips and SiC particles during MA was carried out.

The paper describes an experimental research activity on the application of a polymeric resin reinforced with carbon nanotubes on an ancient timber structures belonging to cultural heritage (Bertolini Cestari et al. in Proc. of SAHC2008. VI International Conference, pp. 941-947, 2008; Marzi in Ph.D. Thesis, 2010; Bertolini Cestari et al. in Proc. of ICRACM- 2010—3rd International Conference on Recent Advances in Composite Materials, 2011). The proposed approach aims at the conservation of a specific wooden joint belonging to traditional constructions.

The conservation of the historical finishes represents a difficult issue, due to their aesthetical and functional roles. In particular, the investigation on surfaces (external o internal) with wall paintings represent a typical case where researchers has some difficulties to apply non invasive diagnostic technique about the detachment of these surfaces. The method here described is aimed at the definition of a scientific method for the evaluation of the adhesion between the fresco and the wall.

The aim of this work is to study the sensing behavior of Sr-doped hematite for soil water content measurement. The material was prepared by solid state reaction from commercial hematite and strontium carbonate heat treated at 900 °C. X-Ray diffraction, scanning electron microscopy and mercury intrusion porosimetry were used for microstructural characterization of the synthesized powder. Sensors were then prepared by uniaxially pressing and by screen-printing, on an alumina substrate, the prepared powder and subsequent firing in the 800–1,000 °C range.

Many materials have a cellular structure, cork, wood, sponge and trabecular bone are natural cellular solids, while engineered honeycombs and foams are now made from polymers, metals, ceramics and glasses. Materials containing tailored porosity exhibit unique properties and features. Therefore, porous materials find nowadays many applications as end products in several technological processes. Contrary to metallic and polymeric porous structures, pores have been traditionally avoided in ceramic components because of their intrinsic brittle nature.

Nanosized powders of La0.80Sr0.20Fe0.95Cu0.05O3−w were investigated in terms of structural, morphological, chemical and surface properties by using several characterization techniques. The XPS and IR measurements showed the presence of surface hydroxide and carbonates species. After calcination of the powders at 900 °C the amount of carbonates decreased but was still significant.

The aim of this paper is to illustrate a multidisciplinary approach to selecting, designing, and evaluating sustainable solutions for energy-efficient buildings that are integrated into their neighborhoods at the early design stage. The paper discusses the Strategic Choice Approach (SCA), a tool which supports decision-makers in shaping problems in complex contexts.

An experimental study was conducted on lab-scale masonry systems constituted by traditional hand-made bricks coupled with external layers of de-humidifying mortar, damaged by means of salt crystallization. The evolution of damage was followed by means of a non-destructive technique denoted as scaling subtraction method (SSM), which is based on the detection and post-processing of the nonlinear response of the system to prescribed ultrasonic excitations.