BEGIN:VCALENDAR VERSION:2.0 PRODID:-//Memento EPFL// BEGIN:VEVENT SUMMARY:MechE Colloquium: High performance bonding by substrate and/or adh esive texturing DTSTART:20200218T121500 DTEND:20200218T131500 DTSTAMP:20260408T020058Z UID:3ec38dc9c29165ebb59272615d59813b988f0afbd3549fe366af6952 CATEGORIES:Conferences - Seminars DESCRIPTION:Prof. Gilles Lubineau\, King Abdullah University of Science an d Technology (KAUST)\, COHMAS Laboratory\nAbstract:\nTo reducing emissions of pollutants\, automotive and aerospace industries are seeking new solut ions to create lighter structures. Extreme lightweight structures can toda y be obtained by using high-performance composites based on continuous fib ers and polymeric matrices. Assembling composite parts is however still a challenge that often jeopardizes the energy efficiency (e.g. bolting or ri veting). Integral adhesive bonding is not used for primary structure today \, because of its extreme sensitivity to the quality of the substrate prep aration that can largely modify the intrinsic performance of the joint. Mo re important for us\, the failure of adhesive joints is often unstable: th e joint behaves well until the development of a catastrophic crack that wo uld propagate throughout the whole joint.\n\nOur objective is here to intr oduce new strategies to equip by design adhesive interfaces with crack arr est features. From a practical point of view\, we are manipulating the R-c urve of the interface by introducing non-local dissipative mechanisms\, su ch as bridging\, that will add to the classical cohesive energy of the adh esive.\n\nTwo different technologies are introduced to realize this toughe ning objective.\nIn the first approach [1-3]\, we are introducing heteroge neous interfacial properties (strength and toughness) between the adhesive layer and the substrate. The introduction of inclusions with higher stren gth results in separating the main crack into two sub-cracks that are prop agating simultaneously and are increasing the effective toughness. In a se cond approach [4]\, bridging ligaments are triggered by introducing a non- symmetric thermoplastic inclusion inside the thermoset based adhesive laye r. The progressive stretch of the thermoplastic ligaments results in an ex tra dissipation that participates in toughening the joints (see figure 1b) .\n\nFor each approach\, this presentation will cover the fundamental conc ept via simulation of the joint failure. Guided by these\, an extensive ex perimental campaign has been performed in which we successfully demonstrat ed that controlling ligament bridging is possible via simple manufacturing techniques or structuration of the interface. These strategies open new d irections towards more trustable adhesive bonding-based solutions.\n\nREFE RENCES\n[1] R. Tao\, M. Alfano and G. Lubineau (2018). Laser-based surface patterning of composite plates for improved secondary adhesive bonding. C omposites Part A: Applied Science and Manufacturing\, v. 109\, pp. 84-94.\ n[2] R. Tao\, M. Alfano and G. Lubineau (2019). In situ analysis of interf acial damage in adhesively bonded composite joints subjected to various su rface pretreatments. Composites Part A\, v. 116\, pp. 216-223.\n[3] R. Tao \, X. Li\, A. Yudhanto\, M. Alfano and G. Lubineau. On controlling interfa cial heterogeneity to trigger bridging in secondary bonded composites: an efficient strategy to introduce crack-arrest features. Submitted.\n[4] A. Yudhanto\, M. Almulhim\, L. Fatta\, O. Alqahtani\, R. Tao\, M. Alfano and G. Lubineau. Enhancement of fracture toughness using 3D-printed thermoplas tic carriers in secondary bonding of CFRP laminate. In preparation.\n\n\nB io:\nProf. Gilles Lubineau is professor of Mechanical Engineering and Chai r of the Faculty of Mechanical Engineering at KAUST. He is principal inves tigator for COHMAS (COmposite and Heterogeneous Materials Analysis and Sim ulation\, an integrated environment for composite engineering that he crea ted in 2009 when joining KAUST).\n\nFollowing his “aggregation” in the oretical mechanics\, Prof. Lubineau earned a PhD degree in Mechanical Engi neering from École Normale Supérieure de Cachan (ENS-Cachan)\, France.  Before joining KAUST\, Pr. Lubineau was a faculty member at the École No rmale Supérieure of Cachan\, and a non-resident faculty member at the Éc ole Polytechnique\, France. He also served as a visiting researcher at UC- Berkeley.\n\nHis fields of research include: integrity at short and/or lon g-term of composite materials and structures\, inverse problems for the id entification of constitutive parameters\, multi-scale coupling technique\, nano and/or multifunctional materials. He covers a wide expertise related to most fields of composite materials\, with over 200 published papers in journal spanning from material science (Advanced Materials\, Macromolecul es\, etc..) all the way to theoretical mechanics (JMPS\, CST\, Scientific Reports) and applied maths (IJNME\, CMAME\, etc.).\n\nHe is also board mem ber for various journals\, including the International Journal of Damage M echanics. Prof. Lubineau is an elected Member of the European Academy of S ciences and Arts. LOCATION:MED 0 1418 https://plan.epfl.ch/?room==MED%200%201418 STATUS:CONFIRMED END:VEVENT END:VCALENDAR