Julien MERIGEON ZHAO

Experience

• 

  Zodiac Aerospace

  Jul 2007 - Aug 2007

  Opérateur Assemblage

  Opérateur Assemblage de sous-ensemble

• 

  EUROCAST - Groupe GMD

  Jun 2010 - Jul 2010

  Opérateur Fonderie

  Opérateur sur presse de 1 000 t pour la fabrication de pièces automobiles en aluminium.Missions :- Réception et traitement des pièces en sortie de presse ;- Contrôle qualité et analyse dimensionnelle.

• 

  Birla Institute of Technology and Science, Pilani - Goa Campus

  Jun 2011 - Aug 2011

  Master's Internship in a Research Lab

  Topic: "Development of a novel aqueous solution based EDTA precursor for synthesis of MnNiZn nanoferrites and their electrical and magnetic properties".Mn-Ni–Zn ferrite shows high saturation magnetization, low coercivity, high resistivity and low dielectric losses. These properties make it a suitable candidate for numerous high frequency applications such as inductance coils, transformer cores, antennas, microwave absorbers.Duties:• Developed a simple chemical method to prepare a nanosized and single phase Mn0.2Ni0.3Zn0.5Fe2O4 powder ;• Investigated the effect of sintering, microstructure and the composition of Mn0.2Ni0.8-xZnxFe2O4 on the electrical resistivity and the magnetic properties.Results:• Synthesized nanostructured single phase Mn-Ni-Zn ferrite powders by an EDTA precursor based method;• Wide range of compositions can easily be prepared by varying the amount of aqueous solution of the starting materials;• Produced single phase, Mn-Ni-Zn ferrite nanopowders (i) at comparatively low temperature (525°C) (ii) by using inexpensive starting materials such as metal nitrates and distilled water as reaction medium and (iii) without using any elaborate experimental setup;• The microstructures of Mn-Ni-Zn ferrite nanopowders consisted of loosely bound agglomerates with large amount of open porosity;• Nanoferrites exhibited high resistivity (107 Ω.cm);• Room temperature magnetization measurements indicated a decrease in saturation magnetization with increase of zinc content in the samples. Show less

• 

  Université de Limoges, Science des Procédés Céramiques et de Traitements de Surface

  Mar 2012 - May 2012

  Master's Internship in a Research Lab

  Topic : “Modeling aggregation of colloidal particles in suspension".Duties :• Analyzed the kinetics of aggregation and aggregate reorganization by Brownian dynamics technique on colloids with a monomodal size distribution in function of the volume fraction of colloids. Results:• Modeled the kinetics of aggregation and reorganization of the aggregates by Brownian dynamics technique on colloidal suspensions of 500 silica particles with a radius of 300 nm;• Identified a significant effect of hydrodynamic interactions especially for higher volume fractions. This effect is limited to very short time because these interactions occured mostly with free particles;• No effect on the shape of aggregates has been exhibited with hydrodynamic interactions.Programming language:• Fortran Show less

• 

  CEA - Commissariat à l'énergie atomique et aux énergies alternatives

  Jun 2012 - Sept 2012

  Engineer's Assistant - Materials for nuclear applications

  Topic : "Correlation between properties and structure of SiC fibers under ion irradiation".Duties :• Developed a temperature control under LABVIEW;• Investigated in-situ mechanical behavior (tensile test, Young's modulus) of SiC fibers;• Explored microstrucutre with different characterization techniques (SEM, TEM, Raman spectroscopy, XRD).Results:• Real-time tensile tests were performed with an in-situ instrument directly in the irradiation line. SiC fibers were loaded with a tension of 300Mpa and a temperature of 1000°C;• Correlation was founded between mechanical behavior and microstructure (mechanical deformation is coupled with the flow and has exhibited a high-temperature radiation creep phenomenon). Show less

• 

  Université d'Angers

  Nov 2012 - Dec 2015

  PhD in Physics - Thin Film for Photovoltaics

  This PhD was carrying out in Laboratoire de Photonique d'Angers (LPhiA) under the supervision of Assoc Prof Mihaela GIRTAN and a starting point for a completely new topic in the laboratory.Topic: "Investigation of encapsulation glass for monocrystalline silicon solar cells"Duties:• Estimated losses due to encapsulation of solar cells;• Reduced degradation caused by UV light;• Performed AntiReflection Coatings (ARC) from TiO2 solution;• Used rare-earth-doped fluoride glass to shift the photon energy of solar spectrum;• Characterized :* Microstructure (XRD, SEM, TEM),* Surface (AFM, Stylus Profilometry),* Optical properties (UV-Vis-NIR, Ellipsometry, PL),* Electrical properties (J-V curve).Results:• ARC have been deposited on the silica glass by sol-gel method. They have exhibited the ideal refractive index for an optimum thickness in order to have zero reflection;• A two-layer system was successfully used as a UV shield on glass to improve efficiency of the cell by 1.3%;• Rare-earth doped glasses - fluorinated matrix ZLAG and ZBLA doped with Pr3+, Tm3+, Yb3+ -were used as front-encapsulation glasses. The effect of doping on electrical performances of encapsulated cells was studied correlated with physical and optical properties of glasses (energy transfer, luminescence, transmittance). Frequency conversion was demonstrated by luminescence for all of the rare-earth-doped samples. Then the most promising result was obtained for codoped Yb3+-Pr3+ ZBLA glass.>> MAJOR RESULT: the benefit of the frequency conversion was shown for the first time in J-V characteristics, codoped Yb3+-Pr3+ ZBLA glass improved the short-circuit current density (Jsc) of a c-Si solar cell by 1.8%.Trainings :• Transmission Electron Microscopy (TEM)• X-ray Photoelectron Spectroscopy (XPS)Other duties:• Contact Angle: designed a setup to measure the contact angle and analyzed the results. Show less

• 

  Istituto Italiano di Tecnologia

  Sept 2016 - Oct 2017

  Industrial Postdoctoral Research Fellow - Soundproofing coating

  Topic: "Formulation of a coating with soundproofing properties on flexible PVC substrates"Duties:• Formulated a coating with inorganic fillers to improve the sound-absorption and sound-reflection properties,• Designed a setup to measure the sound transmission loss of coated and uncoated flexible substrates.• Managed the project independently: Wrote reports with all the technical explanations, set a date and updated the parties about the results, presented Powerpoint presentations, lead the meetings.Results:• Gave a ready-to-apply composition of the coating with high performance fillers to the industrial partner,• Reduced by 70% the sound level transmitted through the substrate with a 1mm-coating. Show less

• 

  AKKA Technologies

  Feb 2019 - Aug 2020

  Engineer on Atmospheric Plasma Spraying process

  Located on Safran Aircraft Engines site.Topic: "Industrialization of Atmospheric Plasma Spraying (APS) coatings on aircraft engines components"Duties:• Developing & supporting APS process for industrialization of repairs on metallic parts (nickel, steel, titanium),• Verifying materials and processes performance,• Qualifying technical specifications,• Ensuring the engineering validation of the process.

• 

  CRMA Aero repair

  Aug 2020 - Mar 2022

  Ingénieur Projection Thermique

  Référent technique sur les activités de l’atelier projection thermique et du laboratoire suivant les missions suivantes :- Assurer le support technique des procédés :• Optimiser les procédés de projection thermique par l’utilisation d’outils d’amélioration continue :Lean, 6 sigma, Observation des postes et application des règles métier, Analyse pourquoi des écarts, pilotage plan d’action, Formation des équipes terrain, mesure des résultats...• Développer et pérenniser le procédé HVOF.• Dans le cadre des projets de développement de nouvelles réparations : accompagner le pilote de projet dans le développement, valider les choix et les orientations techniques, encadrer la phase d’application des process par un rôle de conseil, valider la structure documentaire.• Accompagner et former un back-up au sein de l’équipe.• Participer à des projets d’investissements sur des procédés techniques.• Participer à la veille technologique.- Assurer la structuration et la gestion documentaire :• Structurer la documentation technique de l’atelier et du laboratoire en lien avec les RTP métier et les agents du service (Mise à jour des procédures, création des guides de bonnes pratiques, des supports de formation…)• Mettre en place les cartes de contrôle de suivi du procédé• Mettre à jour réglementairement les gammes et fiches de travail.• Intégrer les Demandes de Modification (DMD) dans les gammes de travail.• Prendre en compte les nouvelles réparations transférées dans la documentation technique.• Assurer la formation et l’accompagnement au changement. Show less

• 

  Safran

  Mar 2022 - now

  Ingénieur Méthodes Projection Thermique

  Spécialiste Procédés de Projection Thermique, mes missions sont de développer, industrialiser et garantir un panel de réparations pour répondre aux besoins croissant des compagnies aériennes.A ce titre mon périmètre d'activité couvre :- La R&T : identifier des procédés nouveaux, des technologies en rupture et des optimisations de paramétrie sur la projection thermique en effectuant une veille active et capitalisant le retour d'expérience terrain ;- L'industrialisation : développer de nouvelles réparations par projection thermique en passant par une analyse détaillée des spécifications, un protocole de mise au point, une campagne d'essais pour ajuster la paramétrie procédé et des caractérisations des éprouvettes et pièces revêtues ;- Le support technique : accompagner les lignes de productions utilisant la projection thermique sur les difficultés techniques, qualifier les installations et garantir leur capabilité à réaliser les opérations, former le personnel pour utiliser les matériels et déceler les dérives ainsi que proposer des axes d'amélioration ;- La Maitrise Statistique des Procédés (MSP) : Suivre et développer la MSP sur les moyens de projection thermique. Show less