Le centre associé au Cetim dans le Grand-Est souffle ses 40 bougies le 6 octobre 2017 à Mulhouse. L’occasion pour les participants de découvrir ses installations, ses savoir-faire et d’inaugurer sa nouvelle plateforme d’expérimentation R&D et de démonstration « matériaux composites et recyclage ».
Créé en 1977, le centre régional d’innovation et de transfert de technologie (CRITT) Cetim-Cermat, centre associé au Cetim, est labellisé centre de ressources technologiques (CRT) en mécanique avancée et membre de l’institut Carnot Mica.
Retrouvez plus d’information sur l’antenne de Metz du Centre sur notre site, rubrique « Actualité », et sur le site Internet du Cetim-Cermat.
A paper published un « Case Studies ni Engineering Failure Analysis », april 2014.
Evaluating and analyzing the risk in the mining industry is a new approach for improving the machinery performance. We use fault tree analysis for modeling occurrence of undesired events (failures) in cement factory. In this model, The authors use fault tree analysis for modeling occurrence of undesired events (failures) in cement factory. They focused on crushing and mixing bed hall department. Analysis of case study extended to system and subsystem levels for each department.
A paper published on « Case Studies in Ingineering Failure Analysis », on april 2014.
This paper investigated the brittle fracture mechanism of a grade E cast steel knuckle that is one of the key components of the coupler for railway wagon. The fracture morphology mainly shows the characteristic of cleavage, quasi-cleavage fracture as well as a little ductile fracture, so the failure of the knuckle can be attributed to brittle fracture distinctly. Moreover, a welding repair area with high hardness is also found in the fracture region, which might initiate micro-cracks on the surface of the knuckle. As a result, it can be inferred that under an impact load that did not exceed material fracture limit, the micro-cracks initiated from weld repair zone propagated rapidly into the inner matrix by continuously fracturing the dendrites along shrinkage porosity regions until the knuckle failed instantly.
In this essay, we will make a thorough study of the technical and administrative factors that contributed to the failure of the Shuttle Challenger project. Starting from paying attention from the planning stage, the implementation of the project, and even the consequences and further investigations, to be able to identify the lessons to be learned in both areas. It is expected that by completing this task, we can notice the critical factors that we need to pay particular attention to approaching ourselves as students that can develop projects successfully.
This paper, published on Engineering Failure Analysis, august 2017, présents corrosion failure analysis of an underground natural gas pipeline. The pipeline material grade is API 5L X65 with 10-in ID. The pipeline transfers multiphase fluid (gas, condensate, and water) from a gas well to a gas gathering plant, located 4200 m away from the well site. A portion of the line failed due to pitting corrosion under unknown circumstances. Based on visual and microscopic analyses and reviewing the background information, the following pitting corrosion sequences were identified: the oversized pipeline changed the dominant flow regime to “stratified”. In the stratified flow regime, the accompanying water phase accumulated in the pipelines’ low points. Considerable concentration of calcium ions along with high pH in CO2 media favored precipitation of calcium carbonate. The relatively thick scales adhered to the pipe surface were partially loosened and removed by the regional turbulent flow. This exposed the fresh steel surface to the corrosive media. The uncovered areas acted as the preferential anodic sites coupled with nearby large cathodic sites which were covered by scales and/or corrosion products. Under such conditions, pits emerged on the steel surface until one of them grew faster and failed the gas pipeline.
A thesis published by Conerstone : A Collection of Scholarly and Creative Works for Minnesota State University, Mankato.
Additive manufacturing (AM) also known as 3D printing has tremendous advancements in récent days with a vast number of applications in industrial, automotive, architecture, consumer projects, fashion, toys, food, art, etc. Composite materials are widely used in structures with weight as a critical factor especially in aerospace industry. Recently, additive manufacturing technology, a rapidly growing innovative technology, has gained lot of importance in making composite materials. The properties of composite materials depend upon the properties of constituent’s matrix and fiber. There is lot of research on effect of fiber orientation on mechanical properties of composite materials made using conventional manufacturing methods. It will be interesting and relevant to study the relationship between the fiber orientation and fiber volume with mechanical properties of additively manufactured composite materials. This thesis work presents experimental investigation of mechanical behavior like tensile strength and fatigue life with variation in fiber orientation and fiber volume fraction of 3D printed composite materials. The aim is to study the best combination of volume fraction of fiber and fiber orientation that has better fatigue strength for additive manufactured composite materials. Using this study, they can decide the type of orientation and volume percent for desired properties. This study also finds the range of fatigue limits of 3d printed composite materials .
An interesting article about failure analysis of impact on glass laminated, published on « Composites Part B »,april 2017.
Laminated glass is a simple sandwiched composite structure, while being widely used in the automotive industry as windshield glazings. It is considered to be safety glass due to its excellent performance in absorbing impact energy and bonding glass fragments. Meanwhile, the impact failure patterns of an automotive windshield glazing contribute to the traffic accident reconstruction. In recent decades, a growing interest has been devoted to the impact failure analysis of automotive laminated glass by means of numerical simulations. The purpose of this work is to present a comprehensive review concerning this aspect. We start by introducing six numerical algorithms for the modeling of the principal damage pattern, glass-ply cracking, followed by the introduction of material models for the plastic interlayer, PVB, and then address three numerical techniques for the adhesion modeling. Three kinds of laminated glass models are summarized. Finally, the performance of the numerical algorithms on the impact failure analysis of laminated glass in terms of glass-ply cracking and acceleration history is thoroughly discussed.
An article published on the JOURNAL OF THE EGYPTIAN SOCIETY OF TRIBOLOGY (VOLUME 14, No. 2, April 2017).
Sand erosion of epoxy resin reinforced by randomly distributed glass fibres and filled by synthetic, paraffin and glycerine oils is studied. The effect of inclination of impact angle and oil content contained in the matrix of epoxy resin is investigated. In addition, the electrostatic charge generated on the eroded surface is measured. Reinforced epoxy demonstrates low erosion resistance compared to unreinforced epoxy. SEM surface examination reveals the effect of inclination angle on wear. Specimens filled by oil lose the electrostatic charge generated from sand erosion in earlier time compared to the unfilled test specimen.