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Mampaey F.,Sirris | Habets D.,Heraeus Holding GmbH | Plessers J.,Heraeus Holding GmbH | Seutens F.,Heraeus Holding GmbH
International Journal of Metalcasting | Year: 2010

Lately, the present authors published a study where oxygen activities were measured using a commercial sensor, which became recently available. In ductile cast iron melts with ferritic and pearlitic structure, optimal properties occur for a well-defined oxygen activity. Castings poured in these circumstances present maximal nodularity, elongation and ferrite content combined with lowest hardness. Additionally, the first results for compacted graphite cast iron were published. The present contribution examines in much more detail the effect of sulfur and oxygen activity on several phenomena important during production of compacted graphite cast iron. These phenomena are the limit for which mechanical properties as defined in ISO16112 are met, the transition from compacted graphite to lamellar graphite and the point at which 20 percent nodularity occurs. Taking into account that the oxygen activity measurement is obtained in about 12 seconds, the sensor seems to be very promising for compacted iron process control. Copyright © 2010 American Foundry Society. Source

Kinet D.,University of Mons | Garray D.,Sirris | Megret P.,University of Mons | Caucheteur C.,University of Mons
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2013

Fibre Bragg gratings (FBGs) are strain sensors that can be embedded into composite materials, without affecting their mechanical performances. In this study, we report the use of a short and weakly tilted FBG inscribed in a single mode highly germanium doped photosensitive optical fibre to discriminate, with a good spatial resolution, strain and temperature effects for structural health monitoring (SHM) application. The transmission spectrum of a weakly tilted FBG (TFBG) presents three regions of interest: the Bragg resonance, the ghost mode resonance and all other cladding mode resonances that are not exploited in this work. We make use of the differential temperature sensitivity of the Bragg mode and the ghost mode to discriminate between temperature and strain effects inside composite materials. © 2013 SPIE. Source

Rahier A.H.,Belgian Nuclear Research Center | Lunardi S.,Belgian Nuclear Research Center | Nicolle F.,National Graduate School of Chemistry, Rennes | George S.M.,Sirris
Talanta | Year: 2010

The sensitive differential pulse anodic stripping voltammetry (DPASV) proposed originally by Ishiyama et al. (2001) has been revised and improved to allow the accurate measurement of silicon on a hanging mercury drop electrode (HMDE) instead of a glassy carbon electrode. We assessed the rate of formation of the partially reduced β-silicododecamolybdate and found that metallic mercury promotes the reaction in the presence of a large concentration of Fe3+. The scope of the method has been broadened by carrying out the measurements in the presence of a constant amount of Fe3+. The limit of detection (LOD) of the method described in the present paper is 100 μg Si g-1 of steel, with a relative precision ranging from 5% to 12%. It can be further enhanced to 700 ng Si g-1 of steel provided the weight of the sample, the dilution factors, the duration of the electrolysis and the ballast of iron are adequately revised. The tolerance to several interfering species has been examined, especially regarding Al3+, Cr3+ and Cr VI species. The method was validated using four low-alloy ferritic steels certified by the National Institute of Standards and Technology (NIST). Its application to nickel base alloys as well as to less complicated matrixes is straightforward. It has also been successfully applied to the determination of free silicon into silicon carbide nano-powder. © 2010 Elsevier B.V. Source

Guo Y.,Catholic University of Leuven | Loenders J.,Sirris | Duflou J.,Catholic University of Leuven | Lauwers B.,Catholic University of Leuven
Procedia CIRP | Year: 2012

Energy reduction in industry has become one of the main objectives for achieving environment friendly manufacturing. In practice, optimization of energy consumption should be implemented while taking into consideration other parameters such as the obtained surface quality. In this paper, an approach which incorporates both energy consumption and surface roughness is presented for optimizing the cutting parameters in finish turning. Based on a new energy model and a surface roughness model, derived for a given machine tool, cutting parameters are optimized to accomplish a precise surface finish with minimum energy consumption. © 2012 The Authors. Source

Patent information service activities cannot always easily be outsourced. External patent information consultants, in spite of their expertise, are sometimes not satisfying the customer's need for high quality searches. The cause of the inadequacy may be the consultant's lack of in-depth knowledge of a particular field of technology and insufficient acquaintance with the subject of study. Customers can cope with this by training the consultant and intensely reviewing the first assignments. If however the customer has limited knowledge of how patent information research is done, training and instructing the consultant and assessing performance may not be practicable. This article illustrates a collaborative approach that a technical consulting organisation which is also a PATLIB centre, having available a multitude of technical research consultants and a small team of patent information specialists, can apply, in association with the customer's own technical and/or product expert, to deal with these possible shortcomings. Sirris launched a pilot project to develop and implement a collaborative model. The article gives an account of how the model was created and implemented, and describes the lessons learnt after 2 years in use. © 2012 Elsevier Ltd. Source

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