Badreddine Saidi - Academia.edu (original) (raw)

Papers by Badreddine Saidi

Université de Technologie de Troyes ; École nationale d'ingénieurs de Tunis (Tunisie), Jul 27, 2018

Journal of Manufacturing and Materials Processing, 2021

Incremental forming is a recent forming process that allows a sheet to be locally deformed with a... more Incremental forming is a recent forming process that allows a sheet to be locally deformed with a hemispherical tool in order to gradually shape it. Despite good lubrication between the sheet and the tip of the smooth hemisphere tool, ductility often occurs, limiting the formability of titanium alloys due to the geometrical inaccuracy of the parts and the inability to form parts with a large depth and wall angle. Several technical solutions are proposed in the literature to increase the working temperature, allowing improvement in the titanium alloys’ formability and reducing the sheet thinning, plastic instability, and failure localization. An experimental procedure and numerical simulation were performed in this study to improve the warm single-point incremental sheet forming of a deep truncated cone in Ti-6Al-4V titanium alloy based on the use of heating cartridges. The effect of the depth part (two experiments with a truncated cone having a depth of 40 and 60 mm) at hot temperat...

Design and Modeling of Mechanical Systems—III, 2017

The single point incremental forming process is an emerging process which presents an alternative... more The single point incremental forming process is an emerging process which presents an alternative to the conventional sheet-metal forming processes like stamping and drawing. It is particularly suitable for prototyping and low production thanks to its flexibility and low cost. The objective of this paper is to study the incremental forming of titanium grade2 and AISI 304L stainless steel sheets. The forming force of sheet titanium grade2 and 304L steel parts formed by single point incremental process depends on different parameters (tool path, tool size, materials and shape, friction, etc.). During the process, considerable forces can occur which must be controlled to ensure the safe use of the CNC milling machine. The aim of this paper is to study the effect of different process parameters on the maximal force. Experimental and numerical studies are performed. An optimization method based on the use of an experimental design and response surface method is used to minimize the forming force.

Journal of the Brazilian Society of Mechanical Sciences and Engineering, 2020

The single-point incremental forming process is an emerging process, which presents an alternativ... more The single-point incremental forming process is an emerging process, which presents an alternative to the conventional sheet metal forming processes like hydroforming and drawing. It is known to be perfectly suited for prototyping and small series. For example, the incremental forming process offers the possibility of manufacturing medical prosthesis or implants specific to each patient, which are more comfortable and guarantee better performance. The customization of this type of product brings better efficiency and better comfort. However, the manufacture of customized titanium prosthesis is not yet industrialized, mainly due to the geometrical inaccuracy of the parts and inability to form parts with a high wall angle. In fact, considerable forces and damage occur during the process limiting the formability. Several studies have already shown that increasing the working temperature allows improving the formability. A reverse engineering approach associated with warm single-point incremental forming process, in order to produce a customized titanium prosthesis, can make the ability to be exploited in the industry to manufacture titanium alloys medical shapes. In this paper, an experimental and numerical study of the warm incremental process based on the use of heat cartridges is performed. The objective is to demonstrate that our low-cost heating system can be used in forming limit angle similar to that obtained with expensive laser heating. The effects of the wall angle at 450 °C on the forming force, thickness distribution and displacement are investigated by producing a truncated cone with Ti-6Al-4V thin sheets. Results show that the formability is significantly improved with the heating. In addition, a thermo-viscoplastic constitutive model is used to simulate the warm incremental forming process. A comparison of the numerical and experimental results shows that the finite element model gives accurate predictions.

To speak about parameters of a single point incremental sheet forming SPIF, we should be found th... more To speak about parameters of a single point incremental sheet forming SPIF, we should be found the good parameter for judgement. More than criterion are defined and the researchers are in front of a beach of traditional criteria, such as, Forces of forming, roughness and the limiting curve forming (FLD). Forces of forming, seems the parameter most significant to exploit in order to find the judgements on the behaviour of the tool and sheet. The first, which developed their work in this direction, are Jeswiet.J and all. Partners of tests are carried out with an aim of seeing the evolution of the efforts of forming by measurement a friction coefficient. Who affects himself in a remarkable way by the factors of the process such as, the thickness of sheet, the geometry of the part obtained and the associated punch movements.

1. École nationale d'ingénieurs de Bizerte (4) Institut nationale des sciences appliquées de ... more 3) École nationale d'ingénieurs de Bizerte (4) Institut nationale des sciences appliquées de Tunis (5) École supérieure des sciences et techniques de Tunis 5 Av Taha Hussein, Montfleury 1008 Tunis, Tunisie (*) Auteur correspondant RÉSUMÉ : L'objectif du présent travail consiste à trouver une démarche permettant de prédire les efforts en cours du procédé de formage incrémental à un point SPIF. Le formage incrémental est un procédé de prototypage rapide permettant de réaliser sans matrice ni de poinçon, en exploitant une machine à commandes numériques d'usinage à 3 axes pour générer des formes très diverses sur des métaux en tôles. Pour parler de paramètres de travail lors d'une opération de formage incrémental, il faut trouver un critère de jugement. Plus qu'un critère est définis et les chercheurs [1, 2, 3] se trouve devant une plage de critères classiques, tel que les efforts mis en jeux, la rugosité et d'autres critères comme la courbe limite de formage (CL...

Sousse 24-26 Mars 2014 Page 1/2 Effets des paramètres de travail, du procédé de formage incrément... more Sousse 24-26 Mars 2014 Page 1/2 Effets des paramètres de travail, du procédé de formage incrémental à un point SPIF sur le comportement des efforts de formage. (1) Institut Supérieur des études technologiques de Radès, BP 176 Radès Médina 2098 Tunisie (2) Laboratoire de génie des matériaux, ENIT -BP 37, 1002 Tunis Le Belvédère, Tunisie (3) Institut nationale des sciences appliquées de Tunis (4) École nationale d'ingénieurs de Bizerte Résumé / Abstract : Le présent document développe les résultats expérimentaux du procédé de formage incrémental à un point SPIF, ainsi qu'une comparaison avec ceux obtenus par une simulation numérique. Mots-clés : SPIF, efforts de formage, paramètres du SPIF, simulation numérique, 1. INTRODUCTION Le procédé du formage incrémental, est un procédé de formage des métaux en tôle, qui met en oeuvres plusieurs paramètres à savoir, les conditions de travail, la trajectoire de l'outil ainsi que le comportement du matériau. Dans cette optique un disp...

Estimation du coefficient de frottement lors d'une opération de formage incrémental à un poin... more Estimation du coefficient de frottement lors d'une opération de formage incrémental à un point SPIF de l'acier 304L Nationale d'ingénieurs de Tunis ENIT -BP 37, 1002 Tunis, Tunisie (4) École Nationale d'ingénieurs de Bizerte ENIB – Menzel-Abderrahmane, Tunisie (*) badreddinesaidi@yahoo.fr Résumé : Le présent manuscrit présente le protocole expérimental, du procédé de formage incrémental à un point SPIF, permettant de prédire les efforts et les paramètres du procédé tel que le coefficient de frottement entre la tôle travaillée et le poinçon. Une compagne d'essai est menée dans le but de voir l'évolution des efforts de formage, qui s'affecte d'une manière remarquable par les facteurs du procédé tels que l'épaisseur de la tôle, la géométrie de la pièce obtenue et les mouvements associés. Notre contribution consiste au développement d'une méthode permettant d'estimer le coefficient de frottement du procédé de formage incrémental à un point SPI...

... (1) Institut Supérieur des études technologiques de Radès, Département de Génie Mécanique, BP... more ... (1) Institut Supérieur des études technologiques de Radès, Département de Génie Mécanique, BP 176 Radès Médina 2098 Tunisie (2) Laboratoire de Mécanique des Solides, des Structures et de Développement Technologique, ESSTT, 5 Av Taha Hussein, Montfleury 1008 ...

Mechanics & Industry, 2015

This paper provides the experimental protocol, of the process of a single point incremental sheet... more This paper provides the experimental protocol, of the process of a single point incremental sheet forming "SPIF", allowing predicting the efforts of forming. To speak about parameters of a single point incremental sheet forming (SPIF), we should find the good parameter for judgement. A prediction of the forming force during the SPIF process is selected to ensure the safe use of the tooling and machinery, in particular when using a robot or a milling machine not designed for the process. During the incremental forming process, considerable forces can occur depending on the studied material, the thickness of the sheet, the tool steps. In this work, the influence of several parameters on the evolution of the axial forming force during the incremental forming of a truncated cone is studied. A set of experiments is carried out using steel and aluminium sheets. The results on the most influent process parameters can be used to optimize the process. The results obtained are compared with those found by finite element simulations.

Journal of the Brazilian Society of Mechanical Sciences and Engineering

The single-point incremental forming process is an emerging process, which presents an alternativ... more The single-point incremental forming process is an emerging process, which presents an alternative to the conventional sheet metal forming processes like hydroforming and drawing. It is known to be perfectly suited for prototyping and small series. For example, the incremental forming process offers the possibility of manufacturing medical prosthesis or implants specific to each patient, which are more comfortable and guarantee better performance. The customization of this type of product brings better efficiency and better comfort. However, the manufacture of customized titanium prosthesis is not yet industrialized, mainly due to the geometrical inaccuracy of the parts and inability to form parts with a high wall angle. In fact, considerable forces and damage occur during the process limiting the formability. Several studies have already shown that increasing the working temperature allows improving the formability. A reverse engineering approach associated with warm single-point incremental forming process, in order to produce a customized titanium prosthesis, can make the ability to be exploited in the industry to manufacture titanium alloys medical shapes. In this paper, an experimental and numerical study of the warm incremental process based on the use of heat cartridges is performed. The objective is to demonstrate that our low-cost heating system can be used in forming limit angle similar to that obtained with expensive laser heating. The effects of the wall angle at 450 °C on the forming force, thickness distribution and displacement are investigated by producing a truncated cone with Ti–6Al–4V thin sheets. Results show that the formability is significantly improved with the heating. In addition, a thermo-viscoplastic constitutive model is used to simulate the warm incremental forming process. A comparison of the numerical and experimental results shows that the finite element model gives accurate predictions.

The International Journal of Advanced Manufacturing Technology

The single-point incremental forming process is an emerging process, which presents an alternativ... more The single-point incremental forming process is an emerging process, which presents an alternative to the conventional sheet metal-forming processes like stamping and drawing. It is known to be perfectly suited for prototyping and small series. The incremental forming process offers the possibility of manufacturing medical prosthesis or implants specific to each patient, which are more comfortable and guarantee better performance. A reverse engineering approach associated with single-point incremental forming process in order to produce a titanium prosthesis of human skull is developed. It allows guaranteeing the high degree of customization required. In this paper, several novel warm forming experimental setup equipped with instruments to measure efforts and temperature monitoring is proposed. This new warm setup is feasible and makes it easy to monitor force and temperature sheet at forming; it gives it the ability to be exploited in the industry of manufacturing titanium alloy medical shapes. The real geometry of a skull prosthesis is re-constructed from a laser scanning technique, and specific treatments are performed until a CAD model is obtained. From it, the forming punch trajectories have been defined, and skull prostheses are manufactured using the technology of single-point incremental forming in titanium material at different temperatures.

Université de Technologie de Troyes ; École nationale d'ingénieurs de Tunis (Tunisie), Jul 27, 2018

Journal of Manufacturing and Materials Processing, 2021

Incremental forming is a recent forming process that allows a sheet to be locally deformed with a... more Incremental forming is a recent forming process that allows a sheet to be locally deformed with a hemispherical tool in order to gradually shape it. Despite good lubrication between the sheet and the tip of the smooth hemisphere tool, ductility often occurs, limiting the formability of titanium alloys due to the geometrical inaccuracy of the parts and the inability to form parts with a large depth and wall angle. Several technical solutions are proposed in the literature to increase the working temperature, allowing improvement in the titanium alloys’ formability and reducing the sheet thinning, plastic instability, and failure localization. An experimental procedure and numerical simulation were performed in this study to improve the warm single-point incremental sheet forming of a deep truncated cone in Ti-6Al-4V titanium alloy based on the use of heating cartridges. The effect of the depth part (two experiments with a truncated cone having a depth of 40 and 60 mm) at hot temperat...

Design and Modeling of Mechanical Systems—III, 2017

The single point incremental forming process is an emerging process which presents an alternative... more The single point incremental forming process is an emerging process which presents an alternative to the conventional sheet-metal forming processes like stamping and drawing. It is particularly suitable for prototyping and low production thanks to its flexibility and low cost. The objective of this paper is to study the incremental forming of titanium grade2 and AISI 304L stainless steel sheets. The forming force of sheet titanium grade2 and 304L steel parts formed by single point incremental process depends on different parameters (tool path, tool size, materials and shape, friction, etc.). During the process, considerable forces can occur which must be controlled to ensure the safe use of the CNC milling machine. The aim of this paper is to study the effect of different process parameters on the maximal force. Experimental and numerical studies are performed. An optimization method based on the use of an experimental design and response surface method is used to minimize the forming force.

Journal of the Brazilian Society of Mechanical Sciences and Engineering, 2020

The single-point incremental forming process is an emerging process, which presents an alternativ... more The single-point incremental forming process is an emerging process, which presents an alternative to the conventional sheet metal forming processes like hydroforming and drawing. It is known to be perfectly suited for prototyping and small series. For example, the incremental forming process offers the possibility of manufacturing medical prosthesis or implants specific to each patient, which are more comfortable and guarantee better performance. The customization of this type of product brings better efficiency and better comfort. However, the manufacture of customized titanium prosthesis is not yet industrialized, mainly due to the geometrical inaccuracy of the parts and inability to form parts with a high wall angle. In fact, considerable forces and damage occur during the process limiting the formability. Several studies have already shown that increasing the working temperature allows improving the formability. A reverse engineering approach associated with warm single-point incremental forming process, in order to produce a customized titanium prosthesis, can make the ability to be exploited in the industry to manufacture titanium alloys medical shapes. In this paper, an experimental and numerical study of the warm incremental process based on the use of heat cartridges is performed. The objective is to demonstrate that our low-cost heating system can be used in forming limit angle similar to that obtained with expensive laser heating. The effects of the wall angle at 450 °C on the forming force, thickness distribution and displacement are investigated by producing a truncated cone with Ti-6Al-4V thin sheets. Results show that the formability is significantly improved with the heating. In addition, a thermo-viscoplastic constitutive model is used to simulate the warm incremental forming process. A comparison of the numerical and experimental results shows that the finite element model gives accurate predictions.

To speak about parameters of a single point incremental sheet forming SPIF, we should be found th... more To speak about parameters of a single point incremental sheet forming SPIF, we should be found the good parameter for judgement. More than criterion are defined and the researchers are in front of a beach of traditional criteria, such as, Forces of forming, roughness and the limiting curve forming (FLD). Forces of forming, seems the parameter most significant to exploit in order to find the judgements on the behaviour of the tool and sheet. The first, which developed their work in this direction, are Jeswiet.J and all. Partners of tests are carried out with an aim of seeing the evolution of the efforts of forming by measurement a friction coefficient. Who affects himself in a remarkable way by the factors of the process such as, the thickness of sheet, the geometry of the part obtained and the associated punch movements.

1. École nationale d'ingénieurs de Bizerte (4) Institut nationale des sciences appliquées de ... more 3) École nationale d'ingénieurs de Bizerte (4) Institut nationale des sciences appliquées de Tunis (5) École supérieure des sciences et techniques de Tunis 5 Av Taha Hussein, Montfleury 1008 Tunis, Tunisie (*) Auteur correspondant RÉSUMÉ : L'objectif du présent travail consiste à trouver une démarche permettant de prédire les efforts en cours du procédé de formage incrémental à un point SPIF. Le formage incrémental est un procédé de prototypage rapide permettant de réaliser sans matrice ni de poinçon, en exploitant une machine à commandes numériques d'usinage à 3 axes pour générer des formes très diverses sur des métaux en tôles. Pour parler de paramètres de travail lors d'une opération de formage incrémental, il faut trouver un critère de jugement. Plus qu'un critère est définis et les chercheurs [1, 2, 3] se trouve devant une plage de critères classiques, tel que les efforts mis en jeux, la rugosité et d'autres critères comme la courbe limite de formage (CL...

Sousse 24-26 Mars 2014 Page 1/2 Effets des paramètres de travail, du procédé de formage incrément... more Sousse 24-26 Mars 2014 Page 1/2 Effets des paramètres de travail, du procédé de formage incrémental à un point SPIF sur le comportement des efforts de formage. (1) Institut Supérieur des études technologiques de Radès, BP 176 Radès Médina 2098 Tunisie (2) Laboratoire de génie des matériaux, ENIT -BP 37, 1002 Tunis Le Belvédère, Tunisie (3) Institut nationale des sciences appliquées de Tunis (4) École nationale d'ingénieurs de Bizerte Résumé / Abstract : Le présent document développe les résultats expérimentaux du procédé de formage incrémental à un point SPIF, ainsi qu'une comparaison avec ceux obtenus par une simulation numérique. Mots-clés : SPIF, efforts de formage, paramètres du SPIF, simulation numérique, 1. INTRODUCTION Le procédé du formage incrémental, est un procédé de formage des métaux en tôle, qui met en oeuvres plusieurs paramètres à savoir, les conditions de travail, la trajectoire de l'outil ainsi que le comportement du matériau. Dans cette optique un disp...

Estimation du coefficient de frottement lors d'une opération de formage incrémental à un poin... more Estimation du coefficient de frottement lors d'une opération de formage incrémental à un point SPIF de l'acier 304L Nationale d'ingénieurs de Tunis ENIT -BP 37, 1002 Tunis, Tunisie (4) École Nationale d'ingénieurs de Bizerte ENIB – Menzel-Abderrahmane, Tunisie (*) badreddinesaidi@yahoo.fr Résumé : Le présent manuscrit présente le protocole expérimental, du procédé de formage incrémental à un point SPIF, permettant de prédire les efforts et les paramètres du procédé tel que le coefficient de frottement entre la tôle travaillée et le poinçon. Une compagne d'essai est menée dans le but de voir l'évolution des efforts de formage, qui s'affecte d'une manière remarquable par les facteurs du procédé tels que l'épaisseur de la tôle, la géométrie de la pièce obtenue et les mouvements associés. Notre contribution consiste au développement d'une méthode permettant d'estimer le coefficient de frottement du procédé de formage incrémental à un point SPI...

... (1) Institut Supérieur des études technologiques de Radès, Département de Génie Mécanique, BP... more ... (1) Institut Supérieur des études technologiques de Radès, Département de Génie Mécanique, BP 176 Radès Médina 2098 Tunisie (2) Laboratoire de Mécanique des Solides, des Structures et de Développement Technologique, ESSTT, 5 Av Taha Hussein, Montfleury 1008 ...

Mechanics & Industry, 2015

This paper provides the experimental protocol, of the process of a single point incremental sheet... more This paper provides the experimental protocol, of the process of a single point incremental sheet forming "SPIF", allowing predicting the efforts of forming. To speak about parameters of a single point incremental sheet forming (SPIF), we should find the good parameter for judgement. A prediction of the forming force during the SPIF process is selected to ensure the safe use of the tooling and machinery, in particular when using a robot or a milling machine not designed for the process. During the incremental forming process, considerable forces can occur depending on the studied material, the thickness of the sheet, the tool steps. In this work, the influence of several parameters on the evolution of the axial forming force during the incremental forming of a truncated cone is studied. A set of experiments is carried out using steel and aluminium sheets. The results on the most influent process parameters can be used to optimize the process. The results obtained are compared with those found by finite element simulations.

Journal of the Brazilian Society of Mechanical Sciences and Engineering

The single-point incremental forming process is an emerging process, which presents an alternativ... more The single-point incremental forming process is an emerging process, which presents an alternative to the conventional sheet metal forming processes like hydroforming and drawing. It is known to be perfectly suited for prototyping and small series. For example, the incremental forming process offers the possibility of manufacturing medical prosthesis or implants specific to each patient, which are more comfortable and guarantee better performance. The customization of this type of product brings better efficiency and better comfort. However, the manufacture of customized titanium prosthesis is not yet industrialized, mainly due to the geometrical inaccuracy of the parts and inability to form parts with a high wall angle. In fact, considerable forces and damage occur during the process limiting the formability. Several studies have already shown that increasing the working temperature allows improving the formability. A reverse engineering approach associated with warm single-point incremental forming process, in order to produce a customized titanium prosthesis, can make the ability to be exploited in the industry to manufacture titanium alloys medical shapes. In this paper, an experimental and numerical study of the warm incremental process based on the use of heat cartridges is performed. The objective is to demonstrate that our low-cost heating system can be used in forming limit angle similar to that obtained with expensive laser heating. The effects of the wall angle at 450 °C on the forming force, thickness distribution and displacement are investigated by producing a truncated cone with Ti–6Al–4V thin sheets. Results show that the formability is significantly improved with the heating. In addition, a thermo-viscoplastic constitutive model is used to simulate the warm incremental forming process. A comparison of the numerical and experimental results shows that the finite element model gives accurate predictions.

The International Journal of Advanced Manufacturing Technology

The single-point incremental forming process is an emerging process, which presents an alternativ... more The single-point incremental forming process is an emerging process, which presents an alternative to the conventional sheet metal-forming processes like stamping and drawing. It is known to be perfectly suited for prototyping and small series. The incremental forming process offers the possibility of manufacturing medical prosthesis or implants specific to each patient, which are more comfortable and guarantee better performance. A reverse engineering approach associated with single-point incremental forming process in order to produce a titanium prosthesis of human skull is developed. It allows guaranteeing the high degree of customization required. In this paper, several novel warm forming experimental setup equipped with instruments to measure efforts and temperature monitoring is proposed. This new warm setup is feasible and makes it easy to monitor force and temperature sheet at forming; it gives it the ability to be exploited in the industry of manufacturing titanium alloy medical shapes. The real geometry of a skull prosthesis is re-constructed from a laser scanning technique, and specific treatments are performed until a CAD model is obtained. From it, the forming punch trajectories have been defined, and skull prostheses are manufactured using the technology of single-point incremental forming in titanium material at different temperatures.