Mechanical, structural and dissolution properties of heat treated thin-film phosphate based glasses

Here we show the deposition of 2.7 μm thick phosphate based glass films produced by magnetron sputtering, followed by post heat treatments at 500 °C. Variations in degradation properties pre and post heat treatment were attributed to the formation of Hematite crystals within a glass matrix, iron oxidation and the depletion of hydrophilic P-O-P bonds within the surface layer. As deposited and heat treated coatings showed interfacial tensile adhesion in excess of 73.6 MPa; which surpassed ISO and FDA requirements for HA coatings. Scratch testing of coatings on polished substrates revealed brittle failure mechanisms, amplified due to heat treatment and interfacial failure occurring from 2.3 to 5.0 N. Coatings that were deposited onto sandblasted substrates to mimic commercial implant surfaces, did not suffer from tensile cracking or trackside delamination showing substantial interfacial improvements to between 8.6 and 11.3 N. An exponential dissolution rate was observed from 0 to 2 h for as deposited coatings, which was eliminated via heat treatment. From 2 to 24 h ion release rates ordered P > Na > Mg > Ca > Fe whilst all coatings exhibited linear degradation rates, which reduced by factors of 2.4–3.0 following heat treatments

Effects of Fe2O3 addition and annealing on the mechanical and dissolution properties of MgO- and CaO-containing phosphate glass fibres for bio-applications

This paper investigated the preparation of phosphate glass fibres (PGFs) in the following systems: i) 45P2O5-5B2O3-5Na2O-(29-x)CaO-16MgO-(x)Fe2O3and ii) 45P2O5-5B2O3-5Na2O-24CaO-(21-x)MgO-(x)Fe2O3(where x = 5, 8 and 11 mol%) for biomedical applications. Continuous fibres of 23 ± 1 μm diameter were prepared via a melt-draw spinning process. Compositions with higher Fe2O3content and higher MgO/CaO ratio required higher melting temperature and longer heating time to achieve glass melts for fibre pulling. The effects of Fe2O3 addition and annealing treatment on mechanical properties and degradation behaviours were also investigated. Adding Fe2O3 was found to increase the tensile strength from 523 ± 63 (Ca-Fe5) to 680 ± 75 MPa (Ca-Fe11), improve the tensile modulus from 72 ± 4 (Ca-Fe5) to 78 ± 3 GPa (Ca-Fe11) and decrease the degradation rate from 4.0 (Mg-Fe5) to 1.9 × 10-6kg m-2s-1(Mg-Fe11). The annealing process reduced the fibre tensile strength by 46% (Ca-Fe5), increased the modulus by 19.6% (Ca-Fe8) and decreased the degradation rate by 89.5% (Mg-Fe11) in comparison to the corresponding as-drawn fibres. Additionally, the annealing process also impeded the formation of precipitate shells and revealed coexistence of the precipitation and the pitting corrosion as fibre degradation behaviours

Characterisation of CorGlaes (R) Pure 107 fibres for biomedical applications

A degradable ultraphosphate (55 mol % P2O5) quinternary phosphate glass composition has been characterised in terms of its chemical, mechanical and degradation properties both as a bulk material and after drawing into fibres. This glass formulation displayed a large processing window simplifying fibre drawing. The fibres displayed stiffness and strength of 65.5 ± 20.8 GPa and 426±143 MPa. While amorphous discs of the glass displayed a linear dissolution rate of 0.004 mg cm−2 h−1 at 37 °C, in a static solution with a reduction in media pH. Once drawn into fibres, the dissolution process dropped the pH to <2 in distilled water, phosphate buffer saline and corrected-simulated body fluid, displaying an autocatalytic effect with >90 % mass loss in 4 days, about seven times faster than anticipated for this solution rate. Only cell culture media was able to buffer the pH taking over a week for full fibre dissolution, however, still four times faster dissolution rate than as a bulk material. However, at early times the development of a HCA layer was seen indicating potential bioactivity. Thus, although initial analysis indicated potential orthopaedic implant applications, autocatalysis leads to accelerating degradation in vitro

Introducing a novel manufacturing process for automotive structural/semi structural composite components

Potential uses of composite materials are currently being investigated by the automotive industry to reduce vehicle weight and CO2 emissions. Existing composite production processes are however, low volume and high cost. The aim of the present study was to develop a novel end-to-end production process to produce a light weight, cost effective polymer composite with reduced TAKT time and potential for structural applications. Components were produced from discontinuous random fibres mixed with an epoxy resin system. Static and dynamic mechanical testing as well as durability tests are in progress to evaluate the performance of these materials. Initial results were compared to Sheet Moulding Compound (SMC) as the benchmark composite material

LA CONSTRUCTION D'UNE CARRIERE INTERNATIONALE (JOUEUR DE TENNIS PROFESSIONNEL. APPROCHE SOCIOLOGIQUE D'UNE PROFESSION AU SEIN DE NEUF PAYS)

CETTE THESE ANALYSE LE CHEMINEMENT QUI MENE A LA PROFESSION DE JOUEUR DE TENNIS PROFESSIONNEL A TRAVERS UNE APPROCHE COMPARATIVE ENTRE NEUF PAYS (ALLEMAGNE, ANGLETERRE, AUSTRALIE, ESPAGNE, ETATS-UNIS, FRANCE, HOLLANDE, REPUBLIQUE TCHEQUE ET SUEDE). LA METHODOLOGIE S'EST AXEE SUR LA COLLECTE D'INFORMATIONS SUR LES DEUX PREMIERES PHASES D'UNE CARRIERE, AU SENS DE GOFFINAN DANS ASILES, C'EST-A-DIREL'APPRENTISSAGE, LA PHASE PRE-PROFESSIONNELLE, ET L'EXERCICE DE LA PROFESSION, LA PHASE PROFESSIONNELLE LES DEBUTS DE LA CARRIERE SE DEROULENT AU SEIN D'UN ESPACE LOCAL (LA FAMILLE, LE CLUB ET L'ECOLE DE LA VILLE DE RESIDENCE) PUIS LES CONTRAINTES QU'EXIGE LA PRATIQUE DU TENNIS DE HAUT NIVEAU OBLIGENT LES JOUEURS LES PLUS TALENTUEUX A SE DIRIGER VERS DES ESPACES DE PRODUCTION DES ELITES. LES DEBUTS DE LA PROFESSIONNALISATION SE FONT SENTIR TANT SUR LE PLAN SUBJECTIF PAR LA TRANSFORMATION DES INDIVIDUS, QUE SUR LE PLAN DES STRUCTURES OBJECTIVES, NOTAMMENT, PAR UNE INTERRUPTION PREMATUREE DE LA SCOLARITE ET UN ELARGISSEMENT DE LEUR ESPACE DE COMPETITION. L'ETAPE SUIVANTE CONCERNE LES DEBUTS PROFESSIONNELS DE LA CARRIERE DE JOUEURS DE TENNIS, C'EST-A- DIRE LES PREMIERES EXPERIENCES DE JOUEURSUR LES TOURNOIS PROFESSIONNELS QUE SONT LES CIRCUITS SATELLITES ET LES FUTURES, LES CATEGORIES D'EPREUVES OUVERTES AUX JOUEURS CLASSES AU-DELA DE LA CINQ-CENTIEME PLACE MONDIALE. DANS LE DERNIER CHAPITRE, NOTRE APPROCHE TRAITE DE LA VIE QUOTIDIENNE DES JOUEURS DE TENNIS PROFESSIONNELS >, CEUX QUI FONT PARTIE DE L'ELITE DES CENT PREMIERS JOUEURS MONDIAUX. QUATRE MODELES DE TRAJECTOIRES SE SONT DEGAGES ET PLUSIEURS CARACTERISTIQUES FORMELLES (LE COACH, LES DEPLACEMENTS, LE PROGRAMME, ETC ) ONT ETE ANALYSEES. CETTE RECHERCHE TRANSNATIONALE DE LA CARRIERE DES JOUEURS DE TENNIS PROFESSIONNELS SOULIGNE QUE LES FORMATIONS SONT ORGANISEES SELON DES LOGIQUES NATIONALES QUI CONFERENT DES CARACTERISTIQUES SPECIFIQUES AU NIVEAU DU SENS PRATIQUE TENNISTIQUE. ENSUITE, L'ESPACE DU TENNIS PROFESSIONNEL ET INTERNATIONAL QU'EST LE CIRCUIT ATP CONTRIBUE A IMPOSER UNE CERTAINE DYNAMIQUE QUI HOMOGENEISE LES COMPORTEMENTS, LA GESTION DU TEMPS, LA NECESSITE D'UN COACH, ETC., MAIS LES STYLES DE JEU VARIES ET DIVERS APPORTENT UNE CERTAINE HETEROGENEITE A CETTE CORPORATION CONSTITUEE D'UNE AGGLOMERATION D'INDIVIDUALITES.NANTES-BU Lettres (441092102) / SudocRENNES2-Sc./Techn.Act.Sportives (352382237) / SudocSudocFranceF

Reconstructing Gladiator Combat: A Multisensory Virtual Reality Training Environment

International audienceThis study presents a research project focused on designing, implementing, and evaluating a multisensory virtual environment to simulate gladiatorial training. The aim is to analyze how immersive experiences impact the acquisition and refinement of technical skills in armed singular dueling. Conducted collaboratively by teams in virtual reality, biomechanics, and history, the project developed a historically contextualized environment centered on the provocator, a specific gladiator type. The virtual environment allows users to train in typical offensive maneuvers, offering a testbed for hypotheses about Roman combat and the effects of external conditions on performance. It serves as both a historical reconstruction tool and an experimental platform for studying ancient martial techniques. Built on rigorous historical and visual research, it uses motion capture technology to accurately recreate combat sequences, enhancing the authenticity and educational value of the simulation. A key contribution of this work lies in advancing the study of gladiatorial techniques, an area often distorted by popular culture. By integrating passive haptic and auditory feedback, the environment enhances sensory immersion, contributing to a deeper and more accurate understanding of gladiatorial practices. This multisensory approach not only supports the preservation of ancient techniques but also sheds light on the physical and cognitive demands faced by historical fighters. Ultimately, this research bridges disciplines-combining historical scholarship, biomechanics, and virtual reality-to offer an innovative way of exploring Roman gladiatorial training. The findings may inform broader discussions on the role of immersive technologies in skill development and historical interpretation within virtual environments

Gladiator training in XR

International audienceThe aim of the work in progress presented here is to design, implement and evaluate a multisensory virtual environment representing a gladiatorial practice context in order to understand the effects of immersion on the training of technical skills related to the field of armed singular duelling. This work, carried out in collaboration between a virtual reality research team, a biomechanics research team and a historian, has produced a virtual environment that puts gladiatorial combat into context. This environment offers training in typical attacks on a specific combatant, the provocator. The aim is to test certain hypotheses about the conduct of gladiatorial combat in Roman times and the impact of external conditions on the performance of these fighters.</div

Gladiator training in XR

International audienceThe aim of the work in progress presented here is to design, implement and evaluate a multisensory virtual environment representing a gladiatorial practice context in order to understand the effects of immersion on the training of technical skills related to the field of armed singular duelling. This work, carried out in collaboration between a virtual reality research team, a biomechanics research team and a historian, has produced a virtual environment that puts gladiatorial combat into context. This environment offers training in typical attacks on a specific combatant, the provocator. The aim is to test certain hypotheses about the conduct of gladiatorial combat in Roman times and the impact of external conditions on the performance of these fighters.</div