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The stability under dynamic mechanical solicitation and with the temperature of the elastomagnetic composite made of Sm2Co7 particles embedded in a silicone matrix is investigated. The thermal stability was examined by DSC measurements. The thermal (up to congruent to 340 degrees C) and mechanical ageing effects on the material elastomagnetic response were investigated by measuring the amplitude, V-0, of the electromotive force induced in a pick-up coil during the dynamic mechanical solicitation of the sample. It was found that for the whole investigation range of temperatures, the V, dependence on the frequency, v, and amplitude, D, of the externally induced deformation is linear and its amplitude is not changing for treatments up to 150 degrees C; for higher temperature treatments the response amplitude is decreasing. The analysis of the response signal (registered at 1 h intervals) after dynamic mechanical solicitation carried out during 48 h, shows the excellent output reliability and no decrease in amplitude with time.

The recent growth of interest of teachers to introduce the use of computer as educational tool encourages the development of didactic environments so that the use of computer classrooms and the resources of the web become daily tools. An aspect of distance education not currently supported by most support environments – commercial and experimental – is related to the possibility of performing laboratory exercises remotely. In the present paper, we illustrate on-going research activities and experimentations within the project LABNET2 of the Italian Interuniversity Computer Science Consortium (CINI) in the National Laboratory for Multimedia and Telematics (ITEM) in Naples. ITEM runs a set of projects, called LABNET, for the experimentation of technologies of remote access to laboratories. Such projects foresee the creation of laboratories, into which real technical-scientific equipments are remotely accessible to teachers and students. Such objective is achieved through the realization of a suitable computer and network infrastructure and the development of necessary software applications. The research activities described here are aimed at remote management of a physics laboratory. By taking advantage of telematics and multimedia technologies, some experiments available in the Physics laboratory (called LAFIDIN) of the Engineering Faculty of the Federico II University of Naples have been made controllable remotely over the Internet. The remote management allows students to perform experimentations, control equipments and visualize the results of the experiments as if these were performed locally. The access to a real laboratory, even if realized through remote control, aims at a greater didactic effectiveness when compared to conventional techniques of virtual laboratories, supported by advanced environments for distance learning. In this paper, we discuss also results of trials run in cooperation with 10 high school institutes of the district of Naples and Avellino. Students performed physics experiments on remote equipments through Internet connection from their schools. During the execution of the experiments, students had the possibility to have a complete vision of what happens in the laboratory through a remote controlled video camera. The camera helps to improve the pedagogical effectiveness of the experiments, remarking the difference with computer simulated experiments.

The coupling between elastic and magnetic properties of composite materials made of magnetic particles uniformly dispersed into an elastic matrix was revised. The influence of particles content and size was considered. A unified simple model of the direct and inverse elastomagnetic effect was furnished explaining the experimental results in different experimental conditions. Some applications of elastomagnetic materials in both sensors and actuators are reported and their potentiality is discussed. The correlation between strain and electric conduction in this kind of materials is also presented and the first experimental results on this topic are reported.

Starting from the basic phenomena of direct and inverse magnetostriction, the status of art of actual application and material development are critically reviewed. Important developments in noise detection and control are pointed out and several innovations are also reported. On the other hand, the crucial improvements to be performed in material performance, devices techniques and modeling are clearly discussed. In particular the first characterization of a new device, based on a novel composite material made of magnetic particles dispersed in an elastic matrix, able of self-attenuation of vibrations also at the resonance frequency, is reported and discussed. Since some problems in vibration control are related to the induction of a spontaneous acoustic mode in the core of the device used for the oscillations detection and/or attenuation, this new system appears to be very interesting for the researchers community involved in noise control and monitoring.

When a constant magnetizing field is applied to a Terfenol sample at a fixed temperature, a small fraction (

Recently, a new ferromagnetic amorphous alloy Fe62.5Co6Ni7.5Zr6Cu1Nb2B15 was produced which was used as core in new magnetoelastic wave resonators. In particular, the achievement of the following innovative properties were obtained: (1) low dimension; (2) zero polarising magnetic field in standard working condition; (3) high sensitivity to local change of magnetic field; (4) low costs. A very high sensitivity to little changes of magnetic field was obtained; it can be used to detect vibrations in the range of mechanical oscillations (1–500 Hz).