Dynamic Compaction of Biomaterial Powders

Dynamic compaction which requires no external heating for consolidation was used to compact hydroxyapatite. Static precompaction of 3 MPa and dynamic compaction using a projectile velocity of 50 m/s resulted in compacts having a compaction degree of 65% and a tensile strength of 12.4 ± 2.7 MPa This strength was very close to that obtained with sintered compacts one and seemed to indicate that some interparticle boundaries had been created during dynamic compaction

Dynamic Behavior of Metals to Magnetic Field Pulses

Mono and/or polycrystalline ring-shaped specimens are submitted to magnetic induction of several Teslas in a field concentrator. In this conditions biaxial stresses are induced inside the specimen, due to radial compression, and lead to the dynamic deformation of metal at strain rates of about 103 s-1 to 104 s-1 and for plastic deformation up to 40%. The test ring geometry allows to get stress and strain states involved and, in particular, to deform the monocrystal (111) in shearing according to . During the magnetic impulsion period, the evolution of deformation has been observed with a high speed camera and then the paths of stress and strain states have been plotted for different field intensities. We compare those paths and energy levels of CFC copper mono and polycrystals with aluminum.Nous soumettons, dans un concentreur de champ, des mono et/ou polycristaux annulaires plans à des inductions magnétiques de quelques Teslas. La compression radiale induit des contraintes biaxiales avec une déformation dynamique de 40% à une vitesse de déformation moyenne de 104 s-1. Nous étudions l'évolution de la déformation notamment pour des monocristaux (111) en cisaillement selon . Durant la première impulsion nous observons par caméra ultra-rapide les échantillons de métaux CFC de cuivres et d'aluminium. Les déformations biaxiales sont présentées et un comparatif est établi entre les valeurs de seuils d'écoulement plastique

On the Use of the Hopkinson Bar for the Determination of the Transient Dynamic Behaviour of Pure Iron

The split Hopkinson pressure bar device is used to study the dynamic response of pure cold-drawn end annealing irons to a sudden decrease of strain rate. Different strain rate history effects are pointed up for the both cold-drawn end annealing states. Applying different unloads to several dynamic microstructural states, allows to access the internal stresses and to characterize the main deformation mechanisms. These mechanisms are firstly thermally-activated then they change into viscous-drag mechanisms when the internal stress saturates and the strain rate become high enough

On the Use of the Hopkinson Bar for the Determination of the Transient Dynamic Behaviour of Pure Iron

The split Hopkinson pressure bar device is used to study the dynamic response of pure cold-drawn end annealing irons to a sudden decrease of strain rate. Different strain rate history effects are pointed up for the both cold-drawn end annealing states. Applying different unloads to several dynamic microstructural states, allows to access the internal stresses and to characterize the main deformation mechanisms. These mechanisms are firstly thermally-activated then they change into viscous-drag mechanisms when the internal stress saturates and the strain rate become high enough.Le montage de compression par barres d'Hopkinson est utilisé pour étudier la réponse dynamique du fer pur écroui et recuit à une brusque variation de vitcsse de déformation. Des effets différents de l'histoire de la vitesse de déformation pour les états écrouis et recuits, sont mis en évidences. Différents déchargements appliqués à plusieurs états microstructuraux dynamiques permettent d'évaluer les contraintes internes et de montrer que les mécanismes de déformation prédominants d'abord activés thermiquement deviennent des mécanismes de frottement visqueux lorsque la contrainte interne est forte et que la vitesse de deformation est suffisamment élevée

The INTAQT project: stakeholders’ perceptions and points of view on products quality

The INTAQT project aims to characterize the links between husbandry systems and the quality of poultry meat, beef and dairy products after consulting at national and Europea levels the actors of each sector on their expectations. The first step was to identify their perceptions and points of view in terms of product quality and this communication focuses on results obtained with producers, processors, retailers and some representatives of citizens’ associations. In addition to the intrinsic quality criteria already foreseen in the project (health, nutrition, organoleptic), stakeholders spontaneously expressed the importance of considering extrinsic criteria related to sustainability (animal welfare, environment, socio-economic aspects) as well as technological quality. The other criteria were mentioned in a variable way depending on the type of stakeholder, the country and the sector concerned. These results are consistent with consumers’ views and they have been taken into account to include other quality criteria in the project

The INTAQT project: stakeholders’ expectations on husbandry systems and innovative practices

The INTAQT project aims to establish the relationship between intrinsic and extrinsic quality criteria of animal products and European husbandry systems. Another aim is to evaluate the impact of innovative husbandry practices on the quality of the products. In order to determine, which husbandry systems and practices the project should study, a European-wide stakeholder consultation of the chicken, beef and dairy value chains was conducted. Stakeholders were presented with a preselection of husbandry systems and were requested to modify or add systems according to their interest, and to name innovative practices to be tested. In total, 161 face-to-face interviews took place between October 2021 and March 2022, followed by 12 national and 3 European group meetings. Overall, stakeholders of all value chains were satisfied with the initially selected systems. Suggestions covered both mainstream systems as well as new, innovative ones, which are emerging due to the growing societal rejection of intensive farming practices. These included systems that improve the farms’ self-autonomy, use local resources or a circular economy, or improve animal welfare and environmental impact. Similarly, actors in all three value chains suggested innovative practices that centre on increased animal welfare and environmental sustainability, thus reflecting a willingness to respond to societal demands