International Journal of Materials and Product Technology, 2008
This paper deals with a new numerical approach to simulate the machining process of the fibre-rei... more This paper deals with a new numerical approach to simulate the machining process of the fibre-reinforced composite materials. The main outcome of the paper is to predict cutting damage in terms of delamination phenomenon between fibres and matrix and matrix cracking. This can be used to compute and rate the influence of working parameters on the cutting forces and damage mechanisms. The characteristics of individual fibres, matrix and fibre/matrix interface are considered to be the most important factors for evaluating the cutting-induced damage in composite materials, from micromechanical viewpoint.
Progressive failure of unidirectional glass fiber-reinforced polymer composites (FRP) was studied... more Progressive failure of unidirectional glass fiber-reinforced polymer composites (FRP) was studied using finite element analysis in orthogonal machining. Chip formation process and damage modes such as matrix cracking, fiber–matrix debonding and fiber breaking were modelled by degrading the material properties. Damage analysis was carried out using Hashin, Maximum stress and Hoffman failure criteria. After damage was detected, selective stiffness degradation was applied to the workpiece material. The objective of this study is to better understand the chip formation process and to analyse the cutting-induced damage from initiation stage until complete chip formation. The effect of the fiber orientation on cutting forces and sub-surface damage was investigated with different failure criteria. The results were addressed in terms of cutting forces evolution and damage progression in the composite structure during machining. It was demonstrated that the use of the stiffness degradation concept with the appropriate failure criterion responds potentially in a predictable fashion to changes in chip formation process for machining of FRPs.
International Journal of Engineering Research in Africa
The fused deposition modeling (FDM) process is used increasingly in the manufacture of mechanical... more The fused deposition modeling (FDM) process is used increasingly in the manufacture of mechanical parts and more particularly in the automotive and aeronautical fields. The purpose of this work is to optimize build orientation for obtaining polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS) samples with the best mechanical properties, dimensional accuracy, surface quality, and minimal total cost. For achieving This, PLA and ABS specimens are fabricated by FDM technology with three build orientations (flat, on edge, upright) and three raster angles (0°, 45°, 90°).at first, the dimensions of the produced samples are measured .secondly, the tensile test, DETLAB equipment was used to obtain tensile stress. In addition, roughness testers were also used to measure surface quality. As a consequence, the findings indicate that the mechanical strength increases with decreasing raster angle and by aligning from upright to flat orientation for both materials due to the fracture me...
The design guidelines available in building codes for steel- and fibre-reinforced polymer (FRP) r... more The design guidelines available in building codes for steel- and fibre-reinforced polymer (FRP) reinforced concrete (RC) beams have been developed on the basis of empirical models. While these models are successfully used for practical purposes, they require continuous improvements with more experimental data. This paper aims to develop a general mathematical model derived from the intrinsic material properties of concrete and certain reinforcements to analyse the bending behaviour of reinforced concrete beams. The proposed model takes into account the effects of non-linearity and ductility on the real behaviour of concrete under compression as well as the concrete tension stiffening. The model focused on analysing the flexural behaviour of rectangular steel, FRP and hybrid FRP–steel RC beams, using the moment–curvature relationship. A general static equilibrium equation was developed and mathematically solved with precise methods to establish a moment–curvature relationship. The ef...
2019 5th International Conference on Optimization and Applications (ICOA)
In view of the modern society desires and requirements, innovation has actually become a crucial ... more In view of the modern society desires and requirements, innovation has actually become a crucial factor for a large sector of industrial companies. Also, competition is no longer only based on the production quality and quantity. For that issue, a significant fragment of research and development studies concentrates on innovation aid tools and methodologies integration amounts the various industry fields. In this context the paper presents a state of the art of the recent research studies exploiting the TRIZ theory, the Russian theory that has been successfully integrated in many fields and industry sectors, also proves its performances resolving innovative problems and improving creativity and ideation spirit in different fields. The presented state of the art is analyzed in terms of the TRIZ exploitation in product design, the field scoring the first level of the TRIZ theory exploitation.
International Journal on Interactive Design and Manufacturing (IJIDeM), 2021
The work presented in this article underlines the embodiment design phase aiming at the determina... more The work presented in this article underlines the embodiment design phase aiming at the determination of different possible architectures of a system according to the energy vision combined with the graph theory. Indeed, the embodiment design phase presents the difficulty of organizing the design alternatives. This difficulty is due to the fact that the various components of the system are not yet fully defined, and there are many arrangement possibilities. In this context, we seek to structure a methodology for the preliminary definition of the technical system architecture, while respecting the TRIZ law of completeness of the system parts. We consider the availability of the transmission elements of the principal energy flow (functional flow). The modeling of the system will concern the flow ensuring the positioning of the system principal component called (contact flow). The modeling of an optimal system composed of the main elements (converter, transmitter, operator, and reference) with a graph ensures the possibility to propose various architectures based on the combinations of these components. The proposed approach consists of three principal phases: appropriate graph-system model association, inappropriate solutions elimination, full system definition, and decision making. An illustration of the methodology is carried out on a wind system example.
The TRIZ theory has demonstrated its effectiveness in solving creative problems in the product de... more The TRIZ theory has demonstrated its effectiveness in solving creative problems in the product design field. However, its exploitation and the application of its various tools and techniques remain difficult for the nonexperts. Generally, the theory does not offer the necessary tools in the preprocessing phases, to support problem modeling. In this context the aim of many research studies is to make easier the TRIZ tools exploitation. The work developed in this paper deals with the TRIZ contradiction matrix exploitation difficulty, and focuses on technical contradictions established for a complex system prioritizing. The technical contradictions prioritizing will be achieved through induced effects impact evaluation on the different specified design objectives. The proposed approach allows analyzing and structuring the design problem in order to exploit the TRIZ contradiction matrix for the design problem resolving. The proposed approach responds to the main problems raised during TRIZ matrix exploitation, especially problems related to the abstraction process ie the standard contradiction formulation and their hierarchy. This aim is achieved through the decision-maker preferences (DMP) integration. An illustration of the proposed approach is carried out with a case study on the wind system.
This paper aims to evaluate the mechanical behavior, dimensional accuracy and total cost of fused... more This paper aims to evaluate the mechanical behavior, dimensional accuracy and total cost of fused deposition modeling (FDM) produced reinforced polyamide (RPA) parts; glass reinforced PA and Kevlar reinforced PA. First of all, the standard specimens are printed by varying three parameters, namely the layer thickness, the print speed and the extrusion temperature. Then, the weight and main dimensions of the obtained samples are measured before the mechanical characterization by tensile test. The results showed the effect of extrusion temperature and layer thickness on material properties is more significant than the impact of print speed. The influence of evaluated factors on the dimensional accuracy and total cost is also observed. Overall, this experimental investigation showed the advantage of reinforcement in enhancing mechanical performance (tensile and fatigue properties) and lead to improving the knowledge about geometrical tolerance of FDM printed reinforced polymer components.
International Journal on Interactive Design and Manufacturing (IJIDeM), 2018
One of the most important aspects of a product design project is innovation and creativity. There... more One of the most important aspects of a product design project is innovation and creativity. Therefore the future designer's ability to be creative and produce innovative and original ideas is inevitable. Training programs are the principle element to help improving ideation spirit in the product design activity. In this issue the paper proposes a design methodology supported by selected innovation tools of the TRIZ theory (an abbreviation of a Russian acronym "Teoriya Resheniya Izobretatelskikh Zadatch" meaning theory of inventive problem solving), subsequently aiming to the development of an interactive design approach. In this work innovation aspect emphasize the preliminary design phase supporting its conceptual design stage with scientific effects to generate ideas in the concept research activity, then the embodiment design stage with TRIZ physical and technical contradictions to resolve an innovative design problem. The proposed methodology adopts an energy vision mainly based on the TRIZ law of completeness of system parts. Results of the proposed methodology exploitation by engineering students in a didactical context are presented in two different case studies for the two preliminary design phases.
2014 International Renewable and Sustainable Energy Conference (IRSEC), 2014
In this paper, we propose to use small wind turbine in design education. The aim is to integrate ... more In this paper, we propose to use small wind turbine in design education. The aim is to integrate the TRIZ theory (Theory of Inventive Problem Solving) as an innovation support tool in the classical design process of Pahl and Beitz. The new proposed methodology is confronted to the design problem of regulation system. The proposed process enhances creativity in the concepts research activity and improves ideation spirit of engineering students.
This paper deals with the analyzing and comparing the thermal performance of heat dissipation sys... more This paper deals with the analyzing and comparing the thermal performance of heat dissipation system and other components in the design of E3D liquefier using Finite Element Modeling (FEM) for three different filaments namely Polycaprolactone (PCL), polylactic acid (PLA) and Acrylonitrile Butadiene Styrene(ABS). This work evaluates the influence of airflow generated by means of a fan coupled to the extruder. The printable materials are also taken as variable in this investigation. The heating process should ensure the balance between proper heating of the material and controlling the temperature along the extruding body, so it reaches above 140 degrees in function of raw material on the tip of the nozzle and must be lower at the top of the liquefier for the correct perseveration of the 3D printer and its durability.
2018 IEEE International Conference on Technology Management, Operations and Decisions (ICTMOD)
this work presents the optimization of the process parameters for the production of PolyLactic Ac... more this work presents the optimization of the process parameters for the production of PolyLactic Acid (PLA) parts by 3d printing. First of all, the standard specimens are printed by varying tree parameters, namely the layer thickness, the infill degree and the deposition orientation. Then, the obtained samples are characterized by tensile tests according to the associated standards. The results showed the significant effect of infill degree and orientation in the increasing of the ultimate tensile strength, and the influence of the layer thickness on the mechanical properties of the prints including how it dramatically changes the filling rate impact. The maximum resistance obtained is around 64 MPa. These tests demonstrated the potential of 3D printing to be exploited in fabrication of functional parts as other convential processes.
Within the context of resolving innovative design problems, this paper proposes an innovation aid... more Within the context of resolving innovative design problems, this paper proposes an innovation aid methodology comprises analysis, formulation and resolution of innovative design problems at the behavioral phase of preliminary design. The behavioral phase is characterized by the existence of induced effects, generally imposed by the technical system components structuring, often considered as a source of harmful effects that must be eliminated. Harmful effects are the sort of design problems frequently observed at the preliminary design behavioral phase, they could be formulated as one or more technical contradictions. Contradiction abstraction model has been developed in TRIZ theory (Russian acronym for "Teoriya Resheniya Izobretatelskikh Zadatch" Theory of Resolution of innovative problems). The contradiction model presents an effective resolution tool mostly used for innovative design problems resolution. The tool exploitation difficulty resides in the abstraction proces...
l'usinage des materiaux composites a matrice polymere et fibres longues induit souvent dans l... more l'usinage des materiaux composites a matrice polymere et fibres longues induit souvent dans la piece usinee des endommagements subsurfaciques comme la fissuration de la matrice, la rupture de la fibre et/ou le delaminage intralaminaire. Dans ce travail de these, deux approches numeriques ont ete developpees pour analyser les aspects micromecaniques et maromecaniques du processus d'usinage. Dans l'approche micromecanique, le materiau est suppose contenir deux phases en liaison parfaite, la fibre et la matrice. Les resultats montrent que les caracteristiques propres a chacun de ces constituants jouent un role determinant dans la reproduction de la formation du copeau, des efforts de coupe et de l'endommagement induit par l'usinage. Dans l'approche macromecanique, le materiau est considere comme homogene equivalent. Deux schemas numeriques ont ete choisis pour integrer le concept de chute de rigidites dans la loi de comportement du materiau usine. Un premier sch...
Je les remercie pour m'avoir guidé efficacement pendant ces années et de m'avoir permis de mener ... more Je les remercie pour m'avoir guidé efficacement pendant ces années et de m'avoir permis de mener à terme cette thèse. Je remercie Messieurs les Professeurs Mohamed Bouidida et Youssef Benghabrit, Directeurs et Directeur Adjoint de l'ENSAM de Meknès (Maroc), Messieurs René Doucet et Michel Herbin, Directeurs successifs du centre de Chalons en Champagne ; qui m'ont permis d'effectuer ce travail dans de bonnes conditions. L'encadrement d'une thèse conditionne bien sûr la qualité des travaux de recherche effectués mais également l'élévation scientifique et humaine du doctorant. Pour toutes ces raisons, j'exprime toute ma gratitude à mon Directeur de thèse, le Professeur Mohamed EL Mansori et mon co-directeur de thèse, le professeur Mohammed Nouari, pour leur implication dans cette tâche. Je tiens à remercier les membres du jury pour l'intérêt qu'ils ont manifesté pour ce travail. Je remercie également, Monsieur le Professeur C. Barlier, directeur de CIRTES et de GIP-INSIC d'avoir accepté de participer à mon jury de thèse ainsi que Monsieur M. J-L Lattaillade, Professeur des Universités aux Arts et Métiers PariTech qui m'a fait le plaisir et l'honneur de présider mon jury de thèse. Messieurs les Professeurs Khalid Lafdi et Francisco Chinesta qui m'ont fait l'honneur d'être rapporteurs de ma thèse, le temps consacré à l'évaluation de mon travail de recherche et l'intérêt qu'ils ont porté aux résultats obtenus. Je remercie également Messieurs Fabrice Pierron Professeurs des Universités aux Arts et Métiers ParisTech et Mohamed Bouidida, Directeur de l'ENSAM de Meknès en qualité de membres invités pour l'examen de mon travail et pour leurs remarques pertinentes. Je remercie aussi mes collègues enseignants et doctorants, qui ont séjourné ou séjournent encore au LMPF-E44106 ainsi que tous les membres du laboratoire, en particulier Alain Giraudeau, Laurence Fouilland, Patrick Ghidossi et Joël Dlvaque, Je leur exprime ma profonde sympathie et je leur souhaite de réussite sur le plan professionnel et privé. J'aimerais ensuite adresser mes plus vifs remerciements à Monsieur Arnauld Delamézier, Directeur des Etudes au GIP-INSIC et à toute l'équipe ERMEP de Saint-Dié des Vosges. IV 3.2.3. Effet de l'angle de dépouille…………………………………………………109 3.2.4. Effet de l'angle de coupe……………………………………………………..111 3.2.5. Effet de l'orientation des fibres………………………………………………112 4. Comparaison entre les approches macromécaniques explicite et implicite développés…………………………………………………………………………………116 4.1. Analyse des efforts de coupe…………………………………………………….116 4.2. Analyse de l'endommagement subsurfacique………………………………….117 5. Extension de l'approche macromécanique explicite pour la simulation de la formation de plusieurs copeaux………………………………………………………….120 5.1. Formation des microcopeaux…………………………………………………….120 5.2. Validation expérimentale des modèles explicites et implicite…………………125 6. Conclusion…………………………………………………….………………………...126 Conclusions et perspectives…………………………….…………………………….129 Références bibliographiques…………………………….…………………………….131 Annexes I…………………………….…………………………………………………….137 Production Scientifique dans le cadre de cette thèse………………………….…137 Revues internationale à comité de lecture…………………………………………...137 Communications dans des congrès Internationaux…………………………………137 Annexes II…………………………………………….……………………………………139 Processus de formation du copeau prédit par l'approche macromécanique implicite pour les différent angles d'orientation des fibres et avec les différents critères de rupture (critère de Hashin, Contrainte maximale et Hoffman)………………………..139 INTRODUCTION Cadre générale de la thèse et contexte scientifique 1 Compte tenu de la constitution de ces matériaux, les opérations de mise en forme par usinage génèrent non seulement une usure prématurée des outils coupants, mais également un endommagement important de la pièce usinée. En effet, le pulleuchage des fibres, la brûlure de la matrice et le délaminage à l'interface fibre/matrice entraînent des endommagements en
International Journal of Materials and Product Technology, 2008
This paper deals with a new numerical approach to simulate the machining process of the fibre-rei... more This paper deals with a new numerical approach to simulate the machining process of the fibre-reinforced composite materials. The main outcome of the paper is to predict cutting damage in terms of delamination phenomenon between fibres and matrix and matrix cracking. This can be used to compute and rate the influence of working parameters on the cutting forces and damage mechanisms. The characteristics of individual fibres, matrix and fibre/matrix interface are considered to be the most important factors for evaluating the cutting-induced damage in composite materials, from micromechanical viewpoint.
Progressive failure of unidirectional glass fiber-reinforced polymer composites (FRP) was studied... more Progressive failure of unidirectional glass fiber-reinforced polymer composites (FRP) was studied using finite element analysis in orthogonal machining. Chip formation process and damage modes such as matrix cracking, fiber–matrix debonding and fiber breaking were modelled by degrading the material properties. Damage analysis was carried out using Hashin, Maximum stress and Hoffman failure criteria. After damage was detected, selective stiffness degradation was applied to the workpiece material. The objective of this study is to better understand the chip formation process and to analyse the cutting-induced damage from initiation stage until complete chip formation. The effect of the fiber orientation on cutting forces and sub-surface damage was investigated with different failure criteria. The results were addressed in terms of cutting forces evolution and damage progression in the composite structure during machining. It was demonstrated that the use of the stiffness degradation concept with the appropriate failure criterion responds potentially in a predictable fashion to changes in chip formation process for machining of FRPs.
International Journal of Engineering Research in Africa
The fused deposition modeling (FDM) process is used increasingly in the manufacture of mechanical... more The fused deposition modeling (FDM) process is used increasingly in the manufacture of mechanical parts and more particularly in the automotive and aeronautical fields. The purpose of this work is to optimize build orientation for obtaining polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS) samples with the best mechanical properties, dimensional accuracy, surface quality, and minimal total cost. For achieving This, PLA and ABS specimens are fabricated by FDM technology with three build orientations (flat, on edge, upright) and three raster angles (0°, 45°, 90°).at first, the dimensions of the produced samples are measured .secondly, the tensile test, DETLAB equipment was used to obtain tensile stress. In addition, roughness testers were also used to measure surface quality. As a consequence, the findings indicate that the mechanical strength increases with decreasing raster angle and by aligning from upright to flat orientation for both materials due to the fracture me...
The design guidelines available in building codes for steel- and fibre-reinforced polymer (FRP) r... more The design guidelines available in building codes for steel- and fibre-reinforced polymer (FRP) reinforced concrete (RC) beams have been developed on the basis of empirical models. While these models are successfully used for practical purposes, they require continuous improvements with more experimental data. This paper aims to develop a general mathematical model derived from the intrinsic material properties of concrete and certain reinforcements to analyse the bending behaviour of reinforced concrete beams. The proposed model takes into account the effects of non-linearity and ductility on the real behaviour of concrete under compression as well as the concrete tension stiffening. The model focused on analysing the flexural behaviour of rectangular steel, FRP and hybrid FRP–steel RC beams, using the moment–curvature relationship. A general static equilibrium equation was developed and mathematically solved with precise methods to establish a moment–curvature relationship. The ef...
2019 5th International Conference on Optimization and Applications (ICOA)
In view of the modern society desires and requirements, innovation has actually become a crucial ... more In view of the modern society desires and requirements, innovation has actually become a crucial factor for a large sector of industrial companies. Also, competition is no longer only based on the production quality and quantity. For that issue, a significant fragment of research and development studies concentrates on innovation aid tools and methodologies integration amounts the various industry fields. In this context the paper presents a state of the art of the recent research studies exploiting the TRIZ theory, the Russian theory that has been successfully integrated in many fields and industry sectors, also proves its performances resolving innovative problems and improving creativity and ideation spirit in different fields. The presented state of the art is analyzed in terms of the TRIZ exploitation in product design, the field scoring the first level of the TRIZ theory exploitation.
International Journal on Interactive Design and Manufacturing (IJIDeM), 2021
The work presented in this article underlines the embodiment design phase aiming at the determina... more The work presented in this article underlines the embodiment design phase aiming at the determination of different possible architectures of a system according to the energy vision combined with the graph theory. Indeed, the embodiment design phase presents the difficulty of organizing the design alternatives. This difficulty is due to the fact that the various components of the system are not yet fully defined, and there are many arrangement possibilities. In this context, we seek to structure a methodology for the preliminary definition of the technical system architecture, while respecting the TRIZ law of completeness of the system parts. We consider the availability of the transmission elements of the principal energy flow (functional flow). The modeling of the system will concern the flow ensuring the positioning of the system principal component called (contact flow). The modeling of an optimal system composed of the main elements (converter, transmitter, operator, and reference) with a graph ensures the possibility to propose various architectures based on the combinations of these components. The proposed approach consists of three principal phases: appropriate graph-system model association, inappropriate solutions elimination, full system definition, and decision making. An illustration of the methodology is carried out on a wind system example.
The TRIZ theory has demonstrated its effectiveness in solving creative problems in the product de... more The TRIZ theory has demonstrated its effectiveness in solving creative problems in the product design field. However, its exploitation and the application of its various tools and techniques remain difficult for the nonexperts. Generally, the theory does not offer the necessary tools in the preprocessing phases, to support problem modeling. In this context the aim of many research studies is to make easier the TRIZ tools exploitation. The work developed in this paper deals with the TRIZ contradiction matrix exploitation difficulty, and focuses on technical contradictions established for a complex system prioritizing. The technical contradictions prioritizing will be achieved through induced effects impact evaluation on the different specified design objectives. The proposed approach allows analyzing and structuring the design problem in order to exploit the TRIZ contradiction matrix for the design problem resolving. The proposed approach responds to the main problems raised during TRIZ matrix exploitation, especially problems related to the abstraction process ie the standard contradiction formulation and their hierarchy. This aim is achieved through the decision-maker preferences (DMP) integration. An illustration of the proposed approach is carried out with a case study on the wind system.
This paper aims to evaluate the mechanical behavior, dimensional accuracy and total cost of fused... more This paper aims to evaluate the mechanical behavior, dimensional accuracy and total cost of fused deposition modeling (FDM) produced reinforced polyamide (RPA) parts; glass reinforced PA and Kevlar reinforced PA. First of all, the standard specimens are printed by varying three parameters, namely the layer thickness, the print speed and the extrusion temperature. Then, the weight and main dimensions of the obtained samples are measured before the mechanical characterization by tensile test. The results showed the effect of extrusion temperature and layer thickness on material properties is more significant than the impact of print speed. The influence of evaluated factors on the dimensional accuracy and total cost is also observed. Overall, this experimental investigation showed the advantage of reinforcement in enhancing mechanical performance (tensile and fatigue properties) and lead to improving the knowledge about geometrical tolerance of FDM printed reinforced polymer components.
International Journal on Interactive Design and Manufacturing (IJIDeM), 2018
One of the most important aspects of a product design project is innovation and creativity. There... more One of the most important aspects of a product design project is innovation and creativity. Therefore the future designer's ability to be creative and produce innovative and original ideas is inevitable. Training programs are the principle element to help improving ideation spirit in the product design activity. In this issue the paper proposes a design methodology supported by selected innovation tools of the TRIZ theory (an abbreviation of a Russian acronym "Teoriya Resheniya Izobretatelskikh Zadatch" meaning theory of inventive problem solving), subsequently aiming to the development of an interactive design approach. In this work innovation aspect emphasize the preliminary design phase supporting its conceptual design stage with scientific effects to generate ideas in the concept research activity, then the embodiment design stage with TRIZ physical and technical contradictions to resolve an innovative design problem. The proposed methodology adopts an energy vision mainly based on the TRIZ law of completeness of system parts. Results of the proposed methodology exploitation by engineering students in a didactical context are presented in two different case studies for the two preliminary design phases.
2014 International Renewable and Sustainable Energy Conference (IRSEC), 2014
In this paper, we propose to use small wind turbine in design education. The aim is to integrate ... more In this paper, we propose to use small wind turbine in design education. The aim is to integrate the TRIZ theory (Theory of Inventive Problem Solving) as an innovation support tool in the classical design process of Pahl and Beitz. The new proposed methodology is confronted to the design problem of regulation system. The proposed process enhances creativity in the concepts research activity and improves ideation spirit of engineering students.
This paper deals with the analyzing and comparing the thermal performance of heat dissipation sys... more This paper deals with the analyzing and comparing the thermal performance of heat dissipation system and other components in the design of E3D liquefier using Finite Element Modeling (FEM) for three different filaments namely Polycaprolactone (PCL), polylactic acid (PLA) and Acrylonitrile Butadiene Styrene(ABS). This work evaluates the influence of airflow generated by means of a fan coupled to the extruder. The printable materials are also taken as variable in this investigation. The heating process should ensure the balance between proper heating of the material and controlling the temperature along the extruding body, so it reaches above 140 degrees in function of raw material on the tip of the nozzle and must be lower at the top of the liquefier for the correct perseveration of the 3D printer and its durability.
2018 IEEE International Conference on Technology Management, Operations and Decisions (ICTMOD)
this work presents the optimization of the process parameters for the production of PolyLactic Ac... more this work presents the optimization of the process parameters for the production of PolyLactic Acid (PLA) parts by 3d printing. First of all, the standard specimens are printed by varying tree parameters, namely the layer thickness, the infill degree and the deposition orientation. Then, the obtained samples are characterized by tensile tests according to the associated standards. The results showed the significant effect of infill degree and orientation in the increasing of the ultimate tensile strength, and the influence of the layer thickness on the mechanical properties of the prints including how it dramatically changes the filling rate impact. The maximum resistance obtained is around 64 MPa. These tests demonstrated the potential of 3D printing to be exploited in fabrication of functional parts as other convential processes.
Within the context of resolving innovative design problems, this paper proposes an innovation aid... more Within the context of resolving innovative design problems, this paper proposes an innovation aid methodology comprises analysis, formulation and resolution of innovative design problems at the behavioral phase of preliminary design. The behavioral phase is characterized by the existence of induced effects, generally imposed by the technical system components structuring, often considered as a source of harmful effects that must be eliminated. Harmful effects are the sort of design problems frequently observed at the preliminary design behavioral phase, they could be formulated as one or more technical contradictions. Contradiction abstraction model has been developed in TRIZ theory (Russian acronym for "Teoriya Resheniya Izobretatelskikh Zadatch" Theory of Resolution of innovative problems). The contradiction model presents an effective resolution tool mostly used for innovative design problems resolution. The tool exploitation difficulty resides in the abstraction proces...
l'usinage des materiaux composites a matrice polymere et fibres longues induit souvent dans l... more l'usinage des materiaux composites a matrice polymere et fibres longues induit souvent dans la piece usinee des endommagements subsurfaciques comme la fissuration de la matrice, la rupture de la fibre et/ou le delaminage intralaminaire. Dans ce travail de these, deux approches numeriques ont ete developpees pour analyser les aspects micromecaniques et maromecaniques du processus d'usinage. Dans l'approche micromecanique, le materiau est suppose contenir deux phases en liaison parfaite, la fibre et la matrice. Les resultats montrent que les caracteristiques propres a chacun de ces constituants jouent un role determinant dans la reproduction de la formation du copeau, des efforts de coupe et de l'endommagement induit par l'usinage. Dans l'approche macromecanique, le materiau est considere comme homogene equivalent. Deux schemas numeriques ont ete choisis pour integrer le concept de chute de rigidites dans la loi de comportement du materiau usine. Un premier sch...
Je les remercie pour m'avoir guidé efficacement pendant ces années et de m'avoir permis de mener ... more Je les remercie pour m'avoir guidé efficacement pendant ces années et de m'avoir permis de mener à terme cette thèse. Je remercie Messieurs les Professeurs Mohamed Bouidida et Youssef Benghabrit, Directeurs et Directeur Adjoint de l'ENSAM de Meknès (Maroc), Messieurs René Doucet et Michel Herbin, Directeurs successifs du centre de Chalons en Champagne ; qui m'ont permis d'effectuer ce travail dans de bonnes conditions. L'encadrement d'une thèse conditionne bien sûr la qualité des travaux de recherche effectués mais également l'élévation scientifique et humaine du doctorant. Pour toutes ces raisons, j'exprime toute ma gratitude à mon Directeur de thèse, le Professeur Mohamed EL Mansori et mon co-directeur de thèse, le professeur Mohammed Nouari, pour leur implication dans cette tâche. Je tiens à remercier les membres du jury pour l'intérêt qu'ils ont manifesté pour ce travail. Je remercie également, Monsieur le Professeur C. Barlier, directeur de CIRTES et de GIP-INSIC d'avoir accepté de participer à mon jury de thèse ainsi que Monsieur M. J-L Lattaillade, Professeur des Universités aux Arts et Métiers PariTech qui m'a fait le plaisir et l'honneur de présider mon jury de thèse. Messieurs les Professeurs Khalid Lafdi et Francisco Chinesta qui m'ont fait l'honneur d'être rapporteurs de ma thèse, le temps consacré à l'évaluation de mon travail de recherche et l'intérêt qu'ils ont porté aux résultats obtenus. Je remercie également Messieurs Fabrice Pierron Professeurs des Universités aux Arts et Métiers ParisTech et Mohamed Bouidida, Directeur de l'ENSAM de Meknès en qualité de membres invités pour l'examen de mon travail et pour leurs remarques pertinentes. Je remercie aussi mes collègues enseignants et doctorants, qui ont séjourné ou séjournent encore au LMPF-E44106 ainsi que tous les membres du laboratoire, en particulier Alain Giraudeau, Laurence Fouilland, Patrick Ghidossi et Joël Dlvaque, Je leur exprime ma profonde sympathie et je leur souhaite de réussite sur le plan professionnel et privé. J'aimerais ensuite adresser mes plus vifs remerciements à Monsieur Arnauld Delamézier, Directeur des Etudes au GIP-INSIC et à toute l'équipe ERMEP de Saint-Dié des Vosges. IV 3.2.3. Effet de l'angle de dépouille…………………………………………………109 3.2.4. Effet de l'angle de coupe……………………………………………………..111 3.2.5. Effet de l'orientation des fibres………………………………………………112 4. Comparaison entre les approches macromécaniques explicite et implicite développés…………………………………………………………………………………116 4.1. Analyse des efforts de coupe…………………………………………………….116 4.2. Analyse de l'endommagement subsurfacique………………………………….117 5. Extension de l'approche macromécanique explicite pour la simulation de la formation de plusieurs copeaux………………………………………………………….120 5.1. Formation des microcopeaux…………………………………………………….120 5.2. Validation expérimentale des modèles explicites et implicite…………………125 6. Conclusion…………………………………………………….………………………...126 Conclusions et perspectives…………………………….…………………………….129 Références bibliographiques…………………………….…………………………….131 Annexes I…………………………….…………………………………………………….137 Production Scientifique dans le cadre de cette thèse………………………….…137 Revues internationale à comité de lecture…………………………………………...137 Communications dans des congrès Internationaux…………………………………137 Annexes II…………………………………………….……………………………………139 Processus de formation du copeau prédit par l'approche macromécanique implicite pour les différent angles d'orientation des fibres et avec les différents critères de rupture (critère de Hashin, Contrainte maximale et Hoffman)………………………..139 INTRODUCTION Cadre générale de la thèse et contexte scientifique 1 Compte tenu de la constitution de ces matériaux, les opérations de mise en forme par usinage génèrent non seulement une usure prématurée des outils coupants, mais également un endommagement important de la pièce usinée. En effet, le pulleuchage des fibres, la brûlure de la matrice et le délaminage à l'interface fibre/matrice entraînent des endommagements en
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