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The electronic power meter sensor module was developed as a part of a global intelligent management system for domestic power consumption management (TELEC) 1 for energy optimisation, both in terms of client costs and energy saving. Abs ract tThere is an increasing concern for the intelligent management of domestic power consumption based on intelligent sensors and actuators (attached to domestic appliances). This paper describes the electronic power meter sensor module of an intelligent management system being developed which is based on a network of functionally independent intelligent sensor and actuator modules. The actuator architecture has different modules to interface and read values from sensors and to communicate with other actuators.The management process is based in data acquired by intelligent sensors and actuators and controls home appliances based on environmental conditions and energy profiles, as well as several factors related to the comfort, commodity and security of users.The main project strategy was the development of a generic system composed of independent functional units (sensor and actuator modules) that can operate in a distributed control mode or under central controller supervision. This configuration gives the user a larger set of control options, as the control of a single appliance, a single space or division or the whole house.The electronic power meter sensor module is responsible for measuring energy and instantaneous and average power. Its functionalities allow it to be used for simple domestic electric power measurement applications. Moreover, it can store power consumption profiles and automatically identify and detect malfunctions of home appliance connected to the network at a given moment. The communication with external devices is implemented using standard serial interfaces.The block diagram of an actuator is illustrated in Fig. 1.

A nanostructured oxide dispersion strengthened (ODS) copper alloy powder, containing an alumina dispersion (about 1% vol.) was prepared by mechanical alloying and subsequently consolidated by hot extrusion. The high temperature stability of the nanostructured and consolidated powders was studied. The stability of the nanostructure was checked with 1 hour heat treatments in the range 400-800ºC. Powders were vacuum encapsulated in copper cans and extruded at temperatures in the range 500-600ºC. The crystallite size of both the as-milled and the heat treated powders was determined with X-ray diffraction (XRD). The line broadening was used to calculate grain (crystallite) size. Two methods were used: the Scherrer equation (SE) and the Williamson-Hall plot (WH). The microstructures of both loose powders and extruded powders were characterised with Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The mechanical properties were assessed with microhardness measurements. The results obtained via XRD with both methods are within the same order of magnitude. A reasonable agreement is also obtained with SEM and TEM observations. The X-ray determination of grain size and the microhardness measurements indicate negligible grain coarsening up to 800ºC. On the other hand, the consolidated powders showed lower hardness values than those of the as-milled and annealed powders. The nanostructured copper alloy studied shows good thermal stability at temperatures up to 800ºC.

Dispersing nanodiamond (nD) particles in metallic matrices can be achieved by ball milling resulting in metal-diamond composite powders. The matrices have been selected considering the whole range of carbon affinity: copper that shows extremely reduced affinity towards carbon phases, potentially compromising the composite interfaces, and nickel and tungsten that are mild and strong carbide formers, respectively, displaying thus intermediate and strong carbon affinities. For the latter matrices, dispersing carbon phases represent a challenge due to carbide conversion.The materials produced are designated as Cu-10nD, Ni-10nD and W-20nD (where 10 and 20 indicate the atomic fraction of nD). Close monitoring of the milling conditions enabled to homogeneously disperse the carbon phases and obtain nanostructured matrices (Figures 1 (a-c)), as well as to minimize milling media contamination and carbide formation, especially in the case of the W-based composite. Apparent interfacial bonding could be inferred the from transmission electron microscopy (TEM) images.The metallic matrices have been subsequently dissolved to allow for a detailed analysis of nanodiamond. Electron diffraction demonstrated that its crystalline structure was preserved during milling (Figure 2). Microhardness measurements revealed remarkable strength enhancements of the nanostructured composites over that of pure metals of comparable grain sizes (Table 1). The strengthening mechanisms that justify the hardness increments in Cu-10nD and Ni-10nD include second-phase reinforcement (due to the potential load bearing ability of diamond), as well as Orowan and solid solution strengthening. The hardening effect observed in the W-20nD composite over that of pure milled tungsten is probably related to the nanodiamond reinforcement, nevertheless the influence of a fine dispersion of carbides cannot be ruled out.This work has been performed under the Contract of Association between EURATOM and Instituto Superior Tecnico. Financial support was also received from the Fundação para a Ciência Tecnologia (FCT) grants with references PTDC/CTM/100163/2008, Pest-OE/SADG/LA0010/2011 and PEST-OE/CTM-UI0084/2011.

Copper has widespread use as engineering material, because of its structural and functional properties, notably high thermal and electrical conductivity. A major drawback of this base metal and its alloys is a relatively low hardness. This precludes its utilization in applications in which both high conductivity and high strength/hardness are needed, e.g. in injection moulds for plastics. Nanostructured metals and nanocomposites are ways to address the low hardness problem, provided the nanostructured material is thermally stable during processing and service. In the present research, composite powders, with 5 to 30 at % nanodiamond, were consolidated into bulk samples. The copper-nanodiamond composite powders were vacuum encapsulated and extruded at 600°C. A significant proportion of the initial hardness in the powders is retained after extrusion. Transmission electron microscopy (TEM) of the extruded material indicates good bonding between the nanodiamond particles and the copper matrix. Raman spectroscopy on the consolidated samples evidences the presence of graphite, possibly due to partial disintegration of ultradisperse nanodiamond agglomerates.