Abbas Tcharkhtchi

Ecole Nationale Supérieure d'Arts et Métiers | ENSAM · M2P

Despite the application of the Additive Manufacturing process and the ability of parts’ construction directly from a 3D model, particular attention should be taken into account to improve their mechanical characteristics. In this paper, we present the effect of individual process variables and the strain-rate sensitivity of Onyx (Nylon mixed with c...

Stereolithography (SLA) is becoming an important fabrication method among the different additive manufacturing techniques. This study investigates the effect of high strain rate on mechanical behavior, considering the fact that materials can be shown different mechanical properties under rapid straining compared to quasi-static loading. In addition...

Several process variables can be taken into account to optimize the Fused Filament Fabrication (FFF) process, a promising Additive Manufacturing technique. To take into account the most important variables, a numerical-experimental roadmap toward the optimization of FFF process by taking into account some physico-chemical and mechanical characteris...

The use of additive manufacturing has been widely developed in the industry due to its ability to make complex shapes. The use of reinforcing fibers has provided a wider design capability in this field. Due to the effect of the number of fibers reinforced used on the mechanical properties, the study of the obtained mechanical properties is of great...

Bonding of parts produced by fused filament fabrication (FFF) significantly depends on the temperature profile of filaments depositing one top of each other. It is necessary to evaluate the temperature profile during fabrication of structures using both theoretical and experimental approaches. This work describes the overall heat transfer (using fi...

The non-isothermal crystallization of the isotactic Polypropylene (iPP) was studied using differential scanning calorimetry and polarizing optical microscopy. Jeziorny’s model and Ozawa’s theoretical approaches were applied to study the non-isothermal kinetics of the iPP. Jeziorny’s approach proved to be the most relevant model to the present mater...

The microstructure deformation of semi-crystalline isotactic polypropylene (iPP) has been studied at a multiscale under a polarizing optical microscope. Using an original machine, the evolution of the microstructure as a function of stress, during a tensile test, was monitored with several photos. Images were captured using a numeric camera every s...

Shape memory effect (SME) of polymers is a property that concerns both, macroscopic and microscopic changes. The variation of internal polymer properties such, as molecular weight (Mw), rigidity, and viscoelasticity could alter its SME. In this study, a bi-parabolic model with six parameters is used to describe the viscoelastic behavior of a shape...

Fused filament fabrication (FFF), an additive manufacturing technique, unlocks alternative possibilities for the production of complex geometries. In this process, the layer-by-layer deposition mechanism and several heat sources make it a thermally driven process. As heat transfer plays a particular role and determines the temperature history of th...

L'étude a pour objet de modéliser les caractéristiques rhéologiques des pièces imprimées en 3D. Pour atteindre cet objectif, une étude bibliographique a été réalisée sur les effets des principales variables du processus de l'évolution de la température et leur impact sur les caractéristiques rhéologiques. Puisque les caractéristiques rhéologiques t...

The paper presents optimization of Fused Deposition Modeling process parameters to improve the cylindricity of 3d printed parts with the Taguchi optimization method. The effect of thickness, infill pattern, number of walls, and Layer height was investigated as variable parameters for experiments on cylindricity. Parts were manufactured by the MarkF...

In this review paper, recent developments in the Fused Filament Fabrication (FFF) approach are provided for composite materials. Influencing parameters in FFF process such as road width, print speed, layer thickness, feed rate and build temperature of the model (both liquefier and envelope temperature), fiber orientation, the layer position, volume...

3D printing, an additive manufacturing process, draws particular attention due to its ability to produce components directly from a 3D model; however, the mechanical properties of the produced pieces are limited. In this paper, we present, from the experimental aspect, the fatigue behavior and damage analysis of polylactic acid (PLA)-Graphene manuf...

Advanced sheet molding compounds (A-SMC) are a new generation of alternative materials to steels for applying in automotive structures. It contains a thermoset matrix involving mineral charge (CaCO3) reinforced with a high fraction of discontinuous bundles of glass fibers (around 50% in mass) compared to the other types of SMC composites. The crash...

In this paper, glass fiber-reinforced polypropylene (GF50-PP) composite composed of long fibers was prepared by the thermo-compression process for the very first time. This composite presents high mechanical strength and is used in infrastructures, which demand resistance against severe conditions. Mechanical strength and multi-scale damage analysi...

The fused filament fabrication (FFF) process of polymer-based composites has been developed due to its capability to make complex geometries and shapes with reasonable mechanical properties. However, the improvement of mechanical properties of the obtained parts and products are still under study and are interesting for designers. There are several...

Drug-eluting stents are desirable platforms for local medicine delivery. However, the incorporation of drugs into polymers can influence the mechanical and physicochemical properties of said matrix, which is a topic that is still poorly understood. In fact, this is more noticeable since the apposition is most often accompanied by mechanical stresse...

Short Fiber Reinforced Composite (SFRC) structures exhibit multiple microstructures (due to material flow during the process). They are generally subjected to variable amplitude loadings. In this context, a robust model is needed to predict fatigue life as a function of microstructure. In this paper, we propose a predictive micromechanical damage-b...

In this study, we aim to evaluate the shape memory effect of a Poly (Caprolactone) (PCL) (40%) and a Styrene-Butadiene-Styrene (SBS) (60%) blend. Shape memory cycle tests are performed at different temperatures to detect the best recovery rate. Under appropriate temperature, the blend recovers substantially its original shape. To study the recovery...

3D printing, an Additive Manufacturing process, comprises the construction of parts by the deposition of extruded filaments, while moving in successive X-Y planes toward Z direction to fabricate 3D parts layer-by-layer. Since filament adhesion relies on several parameters, it is necessary to investigate both experimentally and numerically the physi...

Filament adhesion in 3D printing relies on their temperature profile. It is crucial to evaluate this issue both experimentally and numerically. Using the proposed setup for in-process monitoring of temperature profile, our developed finite volume code indicated very good agreement for the obtained results.

The study purposes to establish the influence of some settings of the conventional rotational-molding process on the aeromechanical performance of a hollow-blade axial fan. It is recognized that the surface state quality, the material characteristics and the blades design have an effect on the performances of the turbomachines. The use of conventio...

In this study, we present a method for prediction of the drug-release profile based on the physical mechanisms that can intervene in drug release from a drug-carrier. The application presented here incorporates the effects of drug concentration and Reynolds number defining the circulating flow in the testing vein. The experimental data used relate...

The microstructural properties and rheological behavior of the long‐glass‐fiber‐reinforced polypropylene (GF50‐PP) composite produced by the compression molding process were studied and modeled. Composite plates of GF50‐PP with different thicknesses of 4, 12, and 24 mm have been used to study the effect of glass fiber distribution and various thick...

The present study aims to assess and characterize the effect of processing parameters including infill pattern and reinforcement type on the dimensional accuracy of products manufactured by Fused Filament Fabrication (FFF) process as well as on the mechanical properties of the printed components. The reinforcements used were carbon, Kevlar and glas...

The original publication of this article unfortunately contains error. The word “extrusion” was spelled incorrectly as “extrussion” in the article title.

The importance of manufacturing of hydrogen fuel tanks due to the application of hydrogen fuels in clean and recyclable energy is one of the most important issues of substituting the petroleum fuels. They consist of two main parts: Plastic liner, as a barrier escape of hydrogen and Carbon Fiber Reinforced Polymer (CFRP) layer to strengthen tanks. T...

Physical and mechanical properties of the drug-incorporated polymer play a significant role in the release behavior from the drug carriers. Understanding the relative extent of variation in the physical and mechanical properties of the polymer makes it possible to improve the design of polymer carriers to obtain better release profile and increase...

Nowadays, polyamide 12 (PA-12) is considered as an interesting polymer in the rotomolding process to manufacture different pieces like the liner part in the storage hydrogen tank (type IV). In this study, the pure polyamide-12 and PA12 pieces, incorporated with 0.5%, 1% and 3% wt Nano Carbon Black (NCB), were manufactured by the rotomolding process...

This paper presents an investigation on the effects of hydrothermal aging on Sheet Molding Compound (SMC) composite. Two different techniques were carried out to study the inner structure of aged SMC composite. Firstly, X-ray micro computed tomography (XµCT) was used to evaluate the changes using 3D images. The results showed cracks in all the comp...

Purpose Fused deposition modeling (FDM) draws particular attention due to its ability to fabricate components directly from a CAD data; however, the mechanical properties of the produced pieces are limited. This paper aims to present the experimental aspect of multi-scale damage analysis and fatigue behavior of polylactic acid (PLA) manufactured by...

In this study, polyurethane‐films loaded with diclofenac were used to analyze the drug release kinetics and mechanisms. For this purpose, the experimental procedures were developed under static and dynamic conditions with different initial drug loads of 10, 20, and 30%. In the dynamic condition, to better simulate the biological flow, drug release...

Fused filament fabrication (FFF), which is an additive manufacturing technique, opens alternative possibilities for complex geometries fabrication. However, its use in functional products is limited due to anisotropic strength issues. Indeed, the strength of FFF fabricated parts across successive layers in the build direction (Z direction) can be s...

The mastering of product reliability is essential for industrial competitiveness. If for metallic materials the topic is well-known, especially in automotive industry, Original Equipment Manufacturers are expecting strong support of their suppliers to full-fill the lack data. This paper presents a new original approach, using a micromechanical base...

Fused filament fabrication, an additive manufacturing technique, is used to produce prototypes and a gradually more important processing route to get final products. Due to the layer-by-layer deposition mechanism involved, bonding between adjacent layers is controlled by the thermal energy of the material being printed. Thus, it is strongly in conj...

The masks have always been mentioned as an effective tool against environmental threats. They are considered as protective equipment to preserve the respiratory system against the non-desirable air droplets and aerosols such as the viral or pollution particles. The aerosols can be pollution existence in the air, or the infectious airborne viruses i...

Sheet Moulding Compounds (SMC) are high strength thermoset moulding materials reinforced with glass treated with thermos-compression. SMC composites combine fibreglass resins and polyester/ phenolic/ vinyl and unsaturated acrylic to produce a high strength moulding compound. These materials are usually formulated to meet the performance requirement...

Short fiber‐reinforced polypropylene is largely used in the automotive industry. Fatigue failure is one of the most failure modes observed in this class of materials. In order to better understand the damage mechanisms and plasticity evolution, this article provides an overall experimental investigation of the mechanical properties of a PPGF40 comp...

Influence of loading temperature on the damage mechanism of polyphenylene sulfide (PPS) reinforced by glass fiber (PPS/GF30) under tension was experimentally studied from quasi-static (QS) to high strain rates. Two kinds of PPS/GF30 samples were prepared: PPS-0° and PPS-90° (correspond to fibers oriented parallel and perpendicular to the injection...

The Shape Memory Effect (SME) does not only concern the macroscopic structure. It concerns also the polymer structure at morphological, macromolecular and molecular scales. This effect may depend on different physicochemical properties like morphology heterogeneity, chain rigidity, steric hindrance, chain polarity, free volume, cross-linking or ent...

Fused Filament Fabrication (FFF) is an additive manufacturing (AM) technique that is used to produce prototypes and a gradually more important processing route to obtain final products. Due to the layer-by-layer deposition mechanism involved, bonding between adjacent layers is controlled by the thermal energy of the material being printed, which st...

Passive safety, particularly in the transport industry, requires maximizing the dissipation of energy and minimizing the decelerations undergone by a vehicle following a violent impact (crash). This paper proposes a strategy for identifying an anisotropic local damage criterion in a moderate dynamic loading for Advanced Sheet Molding Compound (A-SM...

The majority of fatigue life prediction models which have been proposed for the Short Fiber Reinforced Composite (SFRC) materials have been developed for constant temperature. However, in real situations, SFRC structures are subjected to variable temperature. This study focus on the response of SFRC composites subjected to different sequences (or b...

Fused Filament Fabrication is classified as one of the most used processes in Additive Manufacturing rapid prototypes out of polymeric material. Poor strength of the deposited layers is still one of the main critical problems in this process, affecting the mechanical properties of the final parts. To improve the mechanical strength, investigation o...

Fused Filament Fabrication is classified as one of the most used processes in Additive Manufacturing rapid prototypes out of polymeric material. Poor strength of the deposited layers is still one of the main critical problems in this process, affecting the mechanical properties of the final parts. To improve the mechanical strength, investigation o...

Because of the high variability of SMC microstructure due to material flow during thermoforming, fatigue life prediction in real automotive structure represents a huge challenge. In this paper, we present a two-step microstructure selection involving an original ultrasonic method which is briefly presented. Then, on the basis of four selected micro...

To reinforce the environmental standards, we need to strengthen the lightening of vehicles and to generalize new composite materials in order to reduce weight. To use these innovative composite materials in the mass production of automotive parts, it is essential to propose a predictive approach of the S-N curves, which must be established for each...

In this study, the main purpose is to systematically evaluate isothermal and non-isothermal crystallization behavior of short glass fiber-reinforced polyphenylene sulfide polymer composites (PPS/GF) by a wide range of commonly applied models and also to preciously discuss the crystallization evolution and dynamic mechanical properties together with...

Drug-eluting implants with a polymeric matrix are currently widely used and the interest of modeling their behavior is increasing. This article aims to present preliminary results of an in vitro under steady flow, study the behavior of drug-loaded polyurethane samples used as drug delivery matrices. Polyisocyanate and polyol synthesis supplied the...

In this paper, a multi-scale approach is proposed to predict the stiffness reduction of a Sheet-Molding-Compound (SMC) composite submitted to low cycle fatigue (until 2.10⁵ cycles). Strain-controlled tensile fatigue tests (R = 0.1) are carried out at various strain ranges. Damage is investigated at both macroscopic and microscopic scales through th...

In this study, virgin and thermal aged PPS samples were prepared and tested using different techniques such as thermogravimetric analysis (TGA), coupled TGA–Fourier transform infrared spectroscopy (FTIR), and FTIR as well as optical microscopy. Some interesting research results can be summarized as follows: TGA results prove the PPS composite sampl...

The objective of this work is to initiate the discussion about multiphysics relationships between the molten and solid states of high‐density polyethylene (HDPE). The extrusion and the injection processes are employed to prepare samples, and the experimental procedures, using differential scanning calorimetry, dynamic thermomechanical analysis (DMT...

The purpose of this article is to investigate the effect of an initial pre-damage induced by a fatigue loading on the tensile dynamic behavior of Advanced Sheet Molding Compounds (A-SMC). Tension-tension fatigue preloading at a frequency of 30 Hz is performed at various applied stress levels prior to subject the A-SMC specimens to tensile tests at...

Fiber metal laminates (FMLs) are a group of hybrid composite materials consisting of metal and fiber-reinforced polymer layers. In this study, the effects of multi-walled carbon nanotubes (MWCNTs) on the flexural and high-velocity impact behavior of FMLs made up of aluminum 2024-T3 and basalt fibers/epoxy layers were investigated. The fracture surf...

Shape memory polymers (SMPs) gained a high amount of attention during the last decades due wide field of use. The main goal is to produce blends with efficient shape recovery. For this it is essential to simulate the shape memory cycle. Main goals of this work is to find a fast development of viscoelastic models, to consider the effect of stress re...

In this study, we aim to evaluate the effect of enzymatic hydrolysis on aliphatic polyester and on its shape memory blend. Therefore, the hydrolysis of poly (ɛ-caprolactone) (PCL) and of its shape memory polymer (SMP) blend [40% PCL/60% styrene–butadiene–styrene (SBS)] in a solution containing an Amano lipase from pseudomonas fluorescence and a pho...

This paper deals with the development of a numerical scheme to predict the growth of a bubble within a molten polymer. The model consists of one single bubble which expands through the decomposition of a foaming agent in a limited amount of polymer due to the steadily increasing temperature of the melt. The studied process refers to the foaming dur...

In this work, the rotational molding process is developed to manufacture in one piece an axial-flow turbomachine rotor with hollow blades. Giving to our knowledge, this process has never been employed in the making of these turbomachine components. Indeed, the blades of these rotors are typically solid blades and are making by injection molding, ma...

Sheet molding compound (SMC) composite has been studied under humid‐aging conditions. Diffusion of water within the material, as measured by gravimetry, was found to be in good agreement with the “Langmuir‐type” diffusion model developed by Carter and Kibler. In their theory, Carter and Kibler consider the existence of two types of water molecules...

Fused filament fabrication (FFF) is an additive manufacturing (AM) process that provides physical objects commonly used for modeling, prototyping and production applications. The major drawback of this process is poor mechanical property due to the porous structure of final parts. This process requires careful management of coalescence phenomenon....

Shape memory polymers (SMP) are smart materials that have the capacity to deform into a temporary shape and to recover their permanent shape upon exposure to a stimulus like temperature [1]. These materials are used in many field such as the design of biomedical devices and aero-spatial equipment [2]. In this context, we studied the evolution of th...

Poly (phenylene sulfide) (PPS) is one kind of high‐performance polymer with high thermal stability that can be used widely in different industrial domains. However, according to an investigation of the literature, few reviews have comprehensively focused on the continuous development of PPS applications in the past decade. To meet this demand, this...

The main aim of this work is to study the effect of thermal aging on damage mechanisms of a totally recycled composite. The studied material was elaborated by injection molding from a mixture of both recycled matrix (polypropylene‐polyethylene blend) and reinforcement (short carbon fibers). Damage mechanisms analysis was carried out using scanning...

Sheet Molding Compounds (SMCs) with special microstructures are very attractive to use in automobile structures especially when they are accidentally subjected to collision type accidents because of their high energy absorption capacity. These are materials designated as standard SMC, Advanced Sheet Molding Compounds (A-SMC), Low-Density SMC (LD-SM...

Enzymatic Hydrolysis of Poly (ɛ-Caprolactone) (PCL) and of its Shape Memory Polymer (SMP) blend (40%PCL / 60%SBS), in a solution containing a phosphate buffered saline (PBS) and an enzyme from Pseudomonas fluorescens, is realized. The effect of this hydrolytic degradation on crystallinity and thermal properties is investigated using Differential Sc...

In this article, the overall mechanical properties of a short glass fiber‐reinforced polyphenylene sulfide (PPS) composite were tested after oxidation at different temperatures (140, 160, 180, and 200°C), with a maximum oxidation time of approximately 5,300 h. In aspect of thermal aging process, the oxidation rates in 200 and 180°C are considerably...