https://sam.ensam.eu:443 The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material. Mon, 08 Jun 2026 14:22:17 GMT 2026-06-08T14:22:17Z http://hdl.handle.net/10985/8094 High Speed Blanking: An Experimental Method to Measure Induced Cutting Forces GAUDILLIERE, Camille; LARUE, Arnaud; LORONG, Philippe; RANC, Nicolas; MAILLARD, André A new blanking process that involves punch speed up to 10 ms −1 has obvious advantages in increased productivity. However, the inherent dynamics of such a process makes it difficult to develop a practical high speed punch press. The fracture phenomenon governing the blanking process has to be well understood to correctly design the machine support and the tooling. To observe this phenomenon at various controlled blanking speeds a specific experimental device has been developed. The goal is to measure accurately the shear blanking forces imposed on the specimen during blanking. In this paper a new method allowing the blanking forces to be measured and taking into account the proposed test configuration is explained. This technique has been used to determine the blanking forces experienced when forming C40 steel and quantifies the effect of process parameters such as punch die clearance, punch speed, and sheet metal thickness on the blanking force evolution. Lien vers la version éditeur: http://link.springer.com/article/10.1007/s11340-013-9738-1 Tue, 01 Jan 2013 00:00:00 GMT http://hdl.handle.net/10985/8094 2013-01-01T00:00:00Z GAUDILLIERE, Camille LARUE, Arnaud LORONG, Philippe RANC, Nicolas MAILLARD, André A new blanking process that involves punch speed up to 10 ms −1 has obvious advantages in increased productivity. However, the inherent dynamics of such a process makes it difficult to develop a practical high speed punch press. The fracture phenomenon governing the blanking process has to be well understood to correctly design the machine support and the tooling. To observe this phenomenon at various controlled blanking speeds a specific experimental device has been developed. The goal is to measure accurately the shear blanking forces imposed on the specimen during blanking. In this paper a new method allowing the blanking forces to be measured and taking into account the proposed test configuration is explained. This technique has been used to determine the blanking forces experienced when forming C40 steel and quantifies the effect of process parameters such as punch die clearance, punch speed, and sheet metal thickness on the blanking force evolution. http://hdl.handle.net/10985/9956 Simulation numérique du perçage laser par la méthode C-NEM ILLOUL, Lounès; BERTHE, Laurent; LORONG, Philippe; RANC, Nicolas; SCHNEIDER, Matthieu; FAVIER, Véronique; GIRARDOT, Jeremie Ces travaux présentent une alternative numérique au problème de simulation du procédé de perçage par laser. L’utilisation des éléments finis pour modéliser la propagation du trou au cours du temps montre des limites face à un problème de frontières mobiles induit par un changement de phase rapide et des forts gradients thermiques. L’utilisation d’un code C-NEM a donc été testé avec comme objectif de résoudre ces difficultés numériques et d’utiliser le fort potentiel de cette méthode originale. Le principe physique du perçage laser sera rappelé et le modèle mathématique choisi pour le modéliser sera précisé. Un cas test de simulation a été réalisé avec les grandeurs physiques du fer pur afin de valider le choix du code C-NEM. Sun, 01 Jan 2012 00:00:00 GMT http://hdl.handle.net/10985/9956 2012-01-01T00:00:00Z ILLOUL, Lounès BERTHE, Laurent LORONG, Philippe RANC, Nicolas SCHNEIDER, Matthieu FAVIER, Véronique GIRARDOT, Jeremie Ces travaux présentent une alternative numérique au problème de simulation du procédé de perçage par laser. L’utilisation des éléments finis pour modéliser la propagation du trou au cours du temps montre des limites face à un problème de frontières mobiles induit par un changement de phase rapide et des forts gradients thermiques. L’utilisation d’un code C-NEM a donc été testé avec comme objectif de résoudre ces difficultés numériques et d’utiliser le fort potentiel de cette méthode originale. Le principe physique du perçage laser sera rappelé et le modèle mathématique choisi pour le modéliser sera précisé. Un cas test de simulation a été réalisé avec les grandeurs physiques du fer pur afin de valider le choix du code C-NEM. http://hdl.handle.net/10985/9954 Simulation of the laser drilling process with the Constraint Natural Element Method ILLOUL, Lounès; BERTHE, Laurent; LORONG, Philippe; RANC, Nicolas; SCHNEIDER, Matthieu; FAVIER, Véronique; GIRARDOT, Jeremie These works present a numerical alternative to the simulation of the laser drilling process. The use of the finite element method to modeling the hole creation during a laser pulse shows difficulties in front of a moving boundary problem. This moving boundary is induced by a fast phase transformation and also by high thermal gradient. The C-NEM (Constraint Natural Element Method) was tested in order to solve these numerical difficulties and to use the high potential of this original method. The physical interaction of the laser drilling will be reminded and the chosen mathematical model will be specified. A simulation was made with the data for pure iron in order to validate the numerical choice. Sun, 01 Jan 2012 00:00:00 GMT http://hdl.handle.net/10985/9954 2012-01-01T00:00:00Z ILLOUL, Lounès BERTHE, Laurent LORONG, Philippe RANC, Nicolas SCHNEIDER, Matthieu FAVIER, Véronique GIRARDOT, Jeremie These works present a numerical alternative to the simulation of the laser drilling process. The use of the finite element method to modeling the hole creation during a laser pulse shows difficulties in front of a moving boundary problem. This moving boundary is induced by a fast phase transformation and also by high thermal gradient. The C-NEM (Constraint Natural Element Method) was tested in order to solve these numerical difficulties and to use the high potential of this original method. The physical interaction of the laser drilling will be reminded and the chosen mathematical model will be specified. A simulation was made with the data for pure iron in order to validate the numerical choice. http://hdl.handle.net/10985/9746 Prediction of milling-induced vibrations in machining complex parts : numerical and experimental investigation DUCHEMIN, Jérôme; LORONG, Philippe; GUSKOV, Mikhail Avoiding vibrations during machining is an important issue for industry. When dealing with chatter prediction with a numerical approach, several models are required: dynamical models of the workpiece and tool, cutting interaction law and surface representation. The resulting model is a trade-off between the complexity of the above-mentioned ingredients in the context of given solution strategy of equations of motion. Classically, one or two of the above mentioned modeling triad are kept rather rudimentary. These simplifications are often justified depending on the relative importance of phenomena at stake in concrete system. Nevertheless, there are cases when neglecting one of these aspects can lead to considerable alteration in the results (dynamical behavior and resulting machined surface). In the present work, an integrated approach is proposed in order to combine the use of relatively advanced developments along each modeling aspect: a reduced finite element model (using a basis of modes) of the part and tool for the dynamics, segment-wise analytical cutting laws on discretized matter-erasing cutting edges for tool/workpiece interaction, and at last dexel-based geometrical model for the surface evolution. The present work is concerned with a face milling operation of an automobile exhaust manifold. Due to the complexity of the geometry of machined surface, this operation takes place under continuously varying conditions in terms of length of tooth path, of number of engaged teeth and of local workpiece dynamic stiffness. Observations of final surface on actual parts include several zones with considerable vibration-induced defects. Different levels of detail, such as workpiece or tool compliance and damping, are applied in order to appreciate their impacts. The results show that only when flexibility of the part and of the tool are accounted for, the surface defects are close to the reality. Wed, 01 Jan 2014 00:00:00 GMT http://hdl.handle.net/10985/9746 2014-01-01T00:00:00Z DUCHEMIN, Jérôme LORONG, Philippe GUSKOV, Mikhail Avoiding vibrations during machining is an important issue for industry. When dealing with chatter prediction with a numerical approach, several models are required: dynamical models of the workpiece and tool, cutting interaction law and surface representation. The resulting model is a trade-off between the complexity of the above-mentioned ingredients in the context of given solution strategy of equations of motion. Classically, one or two of the above mentioned modeling triad are kept rather rudimentary. These simplifications are often justified depending on the relative importance of phenomena at stake in concrete system. Nevertheless, there are cases when neglecting one of these aspects can lead to considerable alteration in the results (dynamical behavior and resulting machined surface). In the present work, an integrated approach is proposed in order to combine the use of relatively advanced developments along each modeling aspect: a reduced finite element model (using a basis of modes) of the part and tool for the dynamics, segment-wise analytical cutting laws on discretized matter-erasing cutting edges for tool/workpiece interaction, and at last dexel-based geometrical model for the surface evolution. The present work is concerned with a face milling operation of an automobile exhaust manifold. Due to the complexity of the geometry of machined surface, this operation takes place under continuously varying conditions in terms of length of tooth path, of number of engaged teeth and of local workpiece dynamic stiffness. Observations of final surface on actual parts include several zones with considerable vibration-induced defects. Different levels of detail, such as workpiece or tool compliance and damping, are applied in order to appreciate their impacts. The results show that only when flexibility of the part and of the tool are accounted for, the surface defects are close to the reality. http://hdl.handle.net/10985/10174 Solving Stefan problem through C-NEM and level-set approach DAL, Morgan; MONTEIRO, Eric; LORONG, Philippe Numerical methods to solve problems involving discontinuities (jumps, kinks or singularities) on moving internal boundaries have received much attention over the last decade. Among them, the most suitable is probably the extended finite element method (XFEM) in tandem with the level-set technique due to its ability to take into account these discontinuities without matching meshes [1]. The present contribution aims to elaborate a numerical approach to model interfacial discontinu- ities within a meshless context. This approach couples the constrained natural element method (C-NEM) [2] and the level-set technique. In the former, the natural neighbours interpolation, based on a Voronoi diagram, is locally enriched through the partition of unity concept. This enrichment is built from level-set functions that represent and track implicitly discontinuities inside the domain [3]. Like in XFEM, key features of the proposed approach is (i) to determine the intersection between Voronoi cells and discontinuities and (ii) to integrate numerically the weak form over cells containing discontinuities. After testing the proposed method on classical benchmarks, both accuracy and efficiency are examined on the two phase Stefan problem that deals with heat flow involving a solid-liquid phase boundary on which a jump condition must be satisfied [4]. [1] Chessa J., Smolinski P. and Belytschko T. The extended finite element method (XFEM) for solidification problems. Int. J. Numer. Meth. Engng 53:1959–1977 (2002). [2] Yvonnet J., Chinesta F., Lorong P. and Ryckelynck D. The constrained natural element method (C-NEM) for treating thermal models involving moving interfaces. Int. J. Therm. Sci. 44:559–569 (2005). [3] LiuJ.T.,GuS.T.,MonteiroE.andHeQ.C.Aversatileinterfacemodelforthermalconduc- tion phenomena and its numerical implementation by XFEM. Comp. Mech. 53:825–843 (2014). [4] Carslaw H.S. and Jaeger J.C. Conduction of Heat in Solids. 2th Edition, Clarendon Press, (1959). Thu, 01 Jan 2015 00:00:00 GMT http://hdl.handle.net/10985/10174 2015-01-01T00:00:00Z DAL, Morgan MONTEIRO, Eric LORONG, Philippe Numerical methods to solve problems involving discontinuities (jumps, kinks or singularities) on moving internal boundaries have received much attention over the last decade. Among them, the most suitable is probably the extended finite element method (XFEM) in tandem with the level-set technique due to its ability to take into account these discontinuities without matching meshes [1]. The present contribution aims to elaborate a numerical approach to model interfacial discontinu- ities within a meshless context. This approach couples the constrained natural element method (C-NEM) [2] and the level-set technique. In the former, the natural neighbours interpolation, based on a Voronoi diagram, is locally enriched through the partition of unity concept. This enrichment is built from level-set functions that represent and track implicitly discontinuities inside the domain [3]. Like in XFEM, key features of the proposed approach is (i) to determine the intersection between Voronoi cells and discontinuities and (ii) to integrate numerically the weak form over cells containing discontinuities. After testing the proposed method on classical benchmarks, both accuracy and efficiency are examined on the two phase Stefan problem that deals with heat flow involving a solid-liquid phase boundary on which a jump condition must be satisfied [4]. [1] Chessa J., Smolinski P. and Belytschko T. The extended finite element method (XFEM) for solidification problems. Int. J. Numer. Meth. Engng 53:1959–1977 (2002). [2] Yvonnet J., Chinesta F., Lorong P. and Ryckelynck D. The constrained natural element method (C-NEM) for treating thermal models involving moving interfaces. Int. J. Therm. Sci. 44:559–569 (2005). [3] LiuJ.T.,GuS.T.,MonteiroE.andHeQ.C.Aversatileinterfacemodelforthermalconduc- tion phenomena and its numerical implementation by XFEM. Comp. Mech. 53:825–843 (2014). [4] Carslaw H.S. and Jaeger J.C. Conduction of Heat in Solids. 2th Edition, Clarendon Press, (1959). http://hdl.handle.net/10985/9873 Dynamic Study of Thin Wall Part Turning LARUE, Arnaud; PERE-DUARTE, Alexis; LORONG, Philippe The numerical simulation of machining process is a key factor in the control of parts machining process. Its development aims at improving the process reliability and reduces the time spent during the process planning stage. In this context, we use a specific time domain simulation allowing modeling the dynamics of a thin wall part turning operation. After having introduced the basics of the proposed approach we present a specific cutting test that has been designed to specifically measure and control the dynamics of the part and the cutting conditions of a finishing toolpath. The influences of the cutting speed and damping coefficient on the chatter occurrence are discussed. In order to better control the simulation uses, an analysis of the simulation parameters influences on the simulated results is proposed. Sat, 01 Jan 2011 00:00:00 GMT http://hdl.handle.net/10985/9873 2011-01-01T00:00:00Z LARUE, Arnaud PERE-DUARTE, Alexis LORONG, Philippe The numerical simulation of machining process is a key factor in the control of parts machining process. Its development aims at improving the process reliability and reduces the time spent during the process planning stage. In this context, we use a specific time domain simulation allowing modeling the dynamics of a thin wall part turning operation. After having introduced the basics of the proposed approach we present a specific cutting test that has been designed to specifically measure and control the dynamics of the part and the cutting conditions of a finishing toolpath. The influences of the cutting speed and damping coefficient on the chatter occurrence are discussed. In order to better control the simulation uses, an analysis of the simulation parameters influences on the simulated results is proposed. http://hdl.handle.net/10985/7598 Spindle position influence on milling operation stability SELMI, Jaouher; COSTES, Jean-Philippe; LORONG, Philippe; POULACHON, Gerard; CARRAS, Patrice Machine tool is the most used manufacturing means in automotive industry. This kind of manufacturing machine is very expensive and has immediate influence on produced workpiece quality. During machining process design, a tool machine specification sheet is written for each machining operation depending on workpiece required quality, material hardness and cutting conditions. In this way, in order to optimize investments, new machining center should be able to manufacture the quality set by workpiece specification sheet. The main aim of the work presented in this paper is to define and test a new method for spindle dynamic stiffness comparing. The used approach is firstly based on dynamic criteria attained through FRF (Frequency Response Function) measured experimentally on machining center spindle. Secondly, stability limits are calculated and then obtained experimentally. In this case the criterion of st eady state limit is used to compare different spindle configurations regarding the tool. Tue, 01 Jan 2013 00:00:00 GMT http://hdl.handle.net/10985/7598 2013-01-01T00:00:00Z SELMI, Jaouher COSTES, Jean-Philippe LORONG, Philippe POULACHON, Gerard CARRAS, Patrice Machine tool is the most used manufacturing means in automotive industry. This kind of manufacturing machine is very expensive and has immediate influence on produced workpiece quality. During machining process design, a tool machine specification sheet is written for each machining operation depending on workpiece required quality, material hardness and cutting conditions. In this way, in order to optimize investments, new machining center should be able to manufacture the quality set by workpiece specification sheet. The main aim of the work presented in this paper is to define and test a new method for spindle dynamic stiffness comparing. The used approach is firstly based on dynamic criteria attained through FRF (Frequency Response Function) measured experimentally on machining center spindle. Secondly, stability limits are calculated and then obtained experimentally. In this case the criterion of st eady state limit is used to compare different spindle configurations regarding the tool. http://hdl.handle.net/10985/7637 Procédé de perçage par laser : Comparaison entre des données expérimentales et une simulation 2D basée sur la méthode CNEM ILLOUL, Lounès; BERTHE, Laurent; LORONG, Philippe; RANC, Nicolas; SCHNEIDER, Matthieu; FAVIER, Véronique; GIRARDOT, Jeremie This work presents a numerical alternative for the laser drilling simulation problem. Using finite element method is difficult to simulate the hole propagation over time, especially because of moving boundaries due to a fast phase change and high thermal gradients. First, the physical process of the laser drilling and the modeling equations are clarified. Then a comparison between experimental data and simulation outputs regarding the laser peak power is investigated. Tue, 01 Jan 2013 00:00:00 GMT http://hdl.handle.net/10985/7637 2013-01-01T00:00:00Z ILLOUL, Lounès BERTHE, Laurent LORONG, Philippe RANC, Nicolas SCHNEIDER, Matthieu FAVIER, Véronique GIRARDOT, Jeremie This work presents a numerical alternative for the laser drilling simulation problem. Using finite element method is difficult to simulate the hole propagation over time, especially because of moving boundaries due to a fast phase change and high thermal gradients. First, the physical process of the laser drilling and the modeling equations are clarified. Then a comparison between experimental data and simulation outputs regarding the laser peak power is investigated. http://hdl.handle.net/10985/8972 Prediction of the Spindle and Tool Receptance : Industrial Application in Reaming Process; Prediction of the Spindle and Tool Receptance : Industrial Application in Reaming Process SELMI, Jaouher; SELMI, Jaouher; COSTES, Jean-Philippe; COSTES, Jean-Philippe; LORONG, Philippe; LORONG, Philippe; POULACHON, Gerard; POULACHON, Gerard; CARRAS, Patrice; CARRAS, Patrice It is proposed to apply a methodology in order to evaluate the ability of different machining systems (Spindle/Tool) to run a reaming process in a stable way.The methodology is based on an experimental measurement of the dynamic behavior for the system including the spindle and the tool holder. Then, by coupling frequencies response functions, a new system (Spindle/Tool) FRF is predicted at the tool tip. Finally, the critical depth of cut is analytically calculated from the eigenvalues of the characteristic equation of the dynamic reaming process.; It is proposed to apply a methodology in order to evaluate the ability of different machining systems (Spindle/Tool) to run a reaming process in a stable way.The methodology is based on an experimental measurement of the dynamic behavior for the system including the spindle and the tool holder. Then, by coupling frequencies response functions, a new system (Spindle/Tool) FRF is predicted at the tool tip. Finally, the critical depth of cut is analytically calculated from the eigenvalues of the characteristic equation of the dynamic reaming process. Wed, 01 Jan 2014 00:00:00 GMT http://hdl.handle.net/10985/8972 2014-01-01T00:00:00Z SELMI, Jaouher SELMI, Jaouher COSTES, Jean-Philippe COSTES, Jean-Philippe LORONG, Philippe LORONG, Philippe POULACHON, Gerard POULACHON, Gerard CARRAS, Patrice CARRAS, Patrice It is proposed to apply a methodology in order to evaluate the ability of different machining systems (Spindle/Tool) to run a reaming process in a stable way.The methodology is based on an experimental measurement of the dynamic behavior for the system including the spindle and the tool holder. Then, by coupling frequencies response functions, a new system (Spindle/Tool) FRF is predicted at the tool tip. Finally, the critical depth of cut is analytically calculated from the eigenvalues of the characteristic equation of the dynamic reaming process. It is proposed to apply a methodology in order to evaluate the ability of different machining systems (Spindle/Tool) to run a reaming process in a stable way.The methodology is based on an experimental measurement of the dynamic behavior for the system including the spindle and the tool holder. Then, by coupling frequencies response functions, a new system (Spindle/Tool) FRF is predicted at the tool tip. Finally, the critical depth of cut is analytically calculated from the eigenvalues of the characteristic equation of the dynamic reaming process. http://hdl.handle.net/10985/9952 Phénomènes dynamiques en usinage : Prédiction de l’état géométrique des surfaces usinées COFFIGNAL, Gérard; DUCHEMIN, Jérôme; ILLOUL, Lounès; GENGEMBRE, Christophe; LORONG, Philippe; GUSKOV, Mikhail Présentation concernant la modélisation des phénomènes dynamiques en usinage. Cette modélisation a pour particularité de permettre la prédiction de la géométrie des surfaces usinées (défauts de forme, d'ondulation) que la pièce soit considérée comme rigide ou flexible. Tue, 01 Jan 2013 00:00:00 GMT http://hdl.handle.net/10985/9952 2013-01-01T00:00:00Z COFFIGNAL, Gérard DUCHEMIN, Jérôme ILLOUL, Lounès GENGEMBRE, Christophe LORONG, Philippe GUSKOV, Mikhail Présentation concernant la modélisation des phénomènes dynamiques en usinage. Cette modélisation a pour particularité de permettre la prédiction de la géométrie des surfaces usinées (défauts de forme, d'ondulation) que la pièce soit considérée comme rigide ou flexible.