Analysis and modeling of burr formation during the plane milling of cast aluminium alloy using Polycrystalline Diamond Tools

Burr formation is a significant problem during manufacturing, and leads to a lack of geometrical quality through the appearance of undesired and undefined shapes on the workpiece. Thus, understanding the burr formation and elaborating of predictive models are helpful for process design in order to avoid or to reduce burrs and to optimize the strategies for eventual deburring. This study presents both an experimental approach and a model for the plane milling of openwork parts, where burrs are a significant factor. A large-scale analysis of relevant geometrical parameters and their interactions is performed. A phenomenological burr size model is established considering local parameters and the specificities of 3D cutting in milling. Based on local parameters, this article proposes a new methodology to simulate burr height along any part edge and for most face-milling trajectories. Simulations and validations during tool path exits, with changing local parameters, are presented. In addition to the quantitative approach, new 3D aspects of face milling in relation with Exit Order Sequence are developed.contrat ARTS avec MONTUPE

Etude de la formation des bavures en coupe orthogonale à l’outil carbure dans un alliage d’Aluminium – Silicium.

Le but de cet article est d’étudier l’influence des paramètres de coupe sur la formation des bavures en coupe orthogonale. Pour ce faire, une étude en rabotage est réalisée avec des plaquettes carbures, sur un alliage d’Aluminium-Silicium, communément utilisé pour la fonte de culasses automobiles. Cette étude consiste à analyser l’influence de différents paramètres de coupe sur la formation des bavures dans le matériau. Les résultats obtenus permettent de conclure sur l’influence de certains paramètres de coupe sur la formation de la bavure, ainsi que son caractère aléatoire en coupe orthogonale, dû à l’hétérogénéité du matériau

Etude de la formation des bavures en coupe orthogonale à l’outil carbure dans un alliage d’Aluminium – Silicium.

Le but de cet article est d’étudier l’influence des paramètres de coupe sur la formation des bavures en coupe orthogonale. Pour ce faire, une étude en rabotage est réalisée avec des plaquettes carbures, sur un alliage d’Aluminium-Silicium, communément utilisé pour la fonte de culasses automobiles. Cette étude consiste à analyser l’influence de différents paramètres de coupe sur la formation des bavures dans le matériau. Les résultats obtenus permettent de conclure sur l’influence de certains paramètres de coupe sur la formation de la bavure, ainsi que son caractère aléatoire en coupe orthogonale, dû à l’hétérogénéité du matériau

Investigations on exit burr formation mechanisms based on digital image correlation and numerical modelling

Requirements on burr height and burr amount on machined parts are getting stricter. This leads to method development from manufacturing companies to predict burr distribution and its size along part edges. A deeper understanding of burr formation mechanisms will assist to more accurate model development. This study aims to analyze the exit burr formation, which is formed during orthogonal cutting of a brittle cast aluminum alloy. A customized Digital Image Correlation (DIC) system with the help of a high-speed camera was used to measure the displacements fields. It calculates strain fields during burr initiation and development in orthogonal cutting of T7 heat-treated cast Aluminum alloy ENAC-AlSi7Mg0.3 as well. Those results are then qualitatively compared with a numerical model of the burr with chamfer formation developed and simulated using a Finite Element Method (FEM), to ensure a good correspondence between experiments and simulation. This model is used to complete the DIC study of burr with chamfer formation mechanisms during crack propagation leading to chamfer formation. The analysis of numerically obtained stress triaxiality fields and of DIC observations from experiments are compared to the assumptions made from analytical models. Finally, necessary improvements of an existing burr formation analytical model are proposed

Experimental Investigation and Modelling of Burr Formation during Orthogonal Cutting of A356+0.5Cu Aluminium Alloy

Burr formation during parts manufacturing is a significant problem that companies try to minimise or eliminate. The present work aims to study the burr formation mechanisms in a cast aluminium alloy. Orthogonal cutting tests are performed using different uncut chip thicknesses and tool rake angles. To analyse burr formation mechanisms, the work material state of stress and triaxiality distribution in the chip root was investigated via numerical simulations. Results show that the uncut chip thickness has an effect on burr morphology and burr cumulation while tool rake angle influences burr height on high uncut chip thicknesses

Phenomenological study of multivariable effects on exit burr criteria during orthogonal cutting of AlSi alloys using principal components analysis

During machining, burrs are produced along a part’s edges, which can affect a final product lifetime or its efficiency. Moreover, time-consuming and expensive techniques are needed to be applied to remove such burrs. Therefore, companies attempt to reduce burrs formation during machining by manipulating the cutting conditions. This study aims to analyze and quantify the effect of a wide number of parameters on burr formation, resulting from different mechanisms, during orthogonal cutting of AlSi alloys. A highly developed experimental methodology combining high-speed camera recording, laser scanning, and in situ deburring system is used for this study. A statistical analysis is then applied to evaluate relations between controlled parameters and the occurrence of exit burrs morphologies. The results show that the uncut chip thickness influences burr types distribution along the exit edge and chamfer geometry. Among the cutting parameters and tool geometry, tool rake angle is the main parameter affecting burr height. Finally, it is found that none of the burrs geometrical characteristics ranges are piloted by cutting parameters or tool geometry. The assumption of a possible microstructural influence on these outputs is made

Fundamental study of exit burr formation mechanisms during orthogonal cutting of AlSi aluminium alloy

Burr formation during machining is an important issue in industry. It causes an additional deburring operation, which is time consuming and has a negative economic impact. This study aims to analyse burr formation mechanisms and its accumulation in successive passes during orthogonal cutting of a cast aluminium alloy. A customized experimental setup was developed, which includes a high speed imaging system and a laser profilometer. A design of experiments using the setup mentioned previously is carried out and a methodology for geometric burr characterization is developed and applied. Furthermore, statistical representation of the obtained results is performed, which allows the understanding of the geometric heterogeneity influence associated to burr formation mechanisms and to work material microstructure. Based on the exit burr analysis, new geometrical criteria are proposed for the characterisation and the definition of two main burr formation mechanisms. The influence of cutting parameters on burr morphology along the workpiece exit edge is investigated in depth. The results show that two types of burrs can be produced simultaneously along the workpiece exit edge due to the work material microstructure heterogeneity. The results present as well the influence of low uncut chip thickness that leads to a higher proportion of burrs without chamfer. This type of burr is higher and more propice to burr accumulation. After performing several cutting passes, these burrs may be eliminated and replaced by a burr with chamfer

On the influence of "tool - workpiece -machine" vibratory behaviour on the surface quality obtained by superfinish lathing process

Le tournage de superfinition est très spécifique avec une profondeur de passe de l’ordre de 0.05mm et une avance de 0.05mm/tour et permet d’obtenir des surfaces dont la précision et la rugosité sont équivalents à ce que l’on pourrait obtenir par rectification. Cependant, ce procédé est fortement influencé par les caractéristiques dynamiques du système usinant. Le but de nos travaux est de comprendre comment les caractéristiques dynamiques du système Pièce / Outil / Machine (P.O.M.) influencent la qualité de surface obtenue en superfinition à l’outil coupant. Dans un premier temps, nous avons défini, en nous appuyant sur la méthode normalisée du Couple Outil Matière (C.O.M.), des conditions de coupe acceptables et stables. Ensuite, une analyse fréquentielle nous a permis d’identifier trois éléments du système P.O.M. comme sources de vibrations remarquables, à savoir la machine elle-même, la fréquence de rotation de la broche et l’outil utilisé. Puis, nous avons mis en place une démarche expérimentale lourde afin d’évaluer l’influence des sources identifiées sur des critères d’état de surface et sur les vibrations mesurées au niveau de l’outil coupant. Enfin nous avons abordé l’étude des corrélations existantes entre les vibrations et l’état de surface généré en tournage de superfinitionThe superfinishing in turning is very specific, depth of cut about 0.05mm and feed in the order of 0.05mm/rev and allows to produce surfaces with precision and roughness equivalent to grinding process. However, this process is strongly influenced by the dynamic characteristics of the machining system. The aim of our work is to understand how dynamic characteristics of the Part/Tool/Machine (P.T.M.) system influence the surface quality obtained in superfinishing with cutting tool. Initially, we defined acceptable and stable cutting conditions by using the standardized method of the Couple tool-matterial. Then, a frequential analysis enabled us to identify three remarkable sources of vibrations in the P.T.M. system that are the machine tool, the spindle frequency and the tool. Then, we set up an experimental study in order to evaluate the influence of the identified sources of vibrations on surface quality and on the vibrations measured on the cutting tool. Finally we studied the correlations between the vibrations and the surface quality obtained by superfinishing turnin

Contribution à l'étude de l'influence du comportement vibratoire du système "pièce - outil - machine" sur la qualité de surface obtenue en tournage de superfinition

The superfinishing in turning is very specific, depth of cut about 0.05mm and feed in the order of 0.05mm/rev and allows to produce surfaces with precision and roughness equivalent to grinding process. However, this process is strongly influenced by the dynamic characteristics of the machining system. The aim of our work is to understand how dynamic characteristics of the Part/Tool/Machine (P.T.M.) system influence the surface quality obtained in superfinishing with cutting tool. Initially, we defined acceptable and stable cutting conditions by using the standardized method of the Couple tool-matterial. Then, a frequential analysis enabled us to identify three remarkable sources of vibrations in the P.T.M. system that are the machine tool, the spindle frequency and the tool. Then, we set up an experimental study in order to evaluate the influence of the identified sources of vibrations on surface quality and on the vibrations measured on the cutting tool. Finally we studied the correlations between the vibrations and the surface quality obtained by superfinishing turningLe tournage de superfinition est très spécifique avec une profondeur de passe de l'ordre de 0.05mm et une avance de 0.05mm/tour et permet d'obtenir des surfaces dont la précision et la rugosité sont équivalents à ce que l'on pourrait obtenir par rectification. Cependant, ce procédé est fortement influencé par les caractéristiques dynamiques du système usinant. Le but de nos travaux est de comprendre comment les caractéristiques dynamiques du système Pièce / Outil / Machine (P.O.M.) influencent la qualité de surface obtenue en superfinition à l'outil coupant. Dans un premier temps, nous avons défini, en nous appuyant sur la méthode normalisée du Couple Outil Matière (C.O.M.), des conditions de coupe acceptables et stables. Ensuite, une analyse fréquentielle nous a permis d'identifier trois éléments du système P.O.M. comme sources de vibrations remarquables, à savoir la machine elle-même, la fréquence de rotation de la broche et l'outil utilisé. Puis, nous avons mis en place une démarche expérimentale lourde afin d'évaluer l'influence des sources identifiées sur des critères d'état de surface et sur les vibrations mesurées au niveau de l'outil coupant. Enfin nous avons abordé l'étude des corrélations existantes entre les vibrations et l'état de surface généré en tournage de superfinitio

On the influence of "tool - workpiece -machine" vibratory behaviour on the surface quality obtained by superfinish lathing process

Le tournage de superfinition est très spécifique avec une profondeur de passe de l’ordre de 0.05mm et une avance de 0.05mm/tour et permet d’obtenir des surfaces dont la précision et la rugosité sont équivalents à ce que l’on pourrait obtenir par rectification. Cependant, ce procédé est fortement influencé par les caractéristiques dynamiques du système usinant. Le but de nos travaux est de comprendre comment les caractéristiques dynamiques du système Pièce / Outil / Machine (P.O.M.) influencent la qualité de surface obtenue en superfinition à l’outil coupant. Dans un premier temps, nous avons défini, en nous appuyant sur la méthode normalisée du Couple Outil Matière (C.O.M.), des conditions de coupe acceptables et stables. Ensuite, une analyse fréquentielle nous a permis d’identifier trois éléments du système P.O.M. comme sources de vibrations remarquables, à savoir la machine elle-même, la fréquence de rotation de la broche et l’outil utilisé. Puis, nous avons mis en place une démarche expérimentale lourde afin d’évaluer l’influence des sources identifiées sur des critères d’état de surface et sur les vibrations mesurées au niveau de l’outil coupant. Enfin nous avons abordé l’étude des corrélations existantes entre les vibrations et l’état de surface généré en tournage de superfinitionThe superfinishing in turning is very specific, depth of cut about 0.05mm and feed in the order of 0.05mm/rev and allows to produce surfaces with precision and roughness equivalent to grinding process. However, this process is strongly influenced by the dynamic characteristics of the machining system. The aim of our work is to understand how dynamic characteristics of the Part/Tool/Machine (P.T.M.) system influence the surface quality obtained in superfinishing with cutting tool. Initially, we defined acceptable and stable cutting conditions by using the standardized method of the Couple tool-matterial. Then, a frequential analysis enabled us to identify three remarkable sources of vibrations in the P.T.M. system that are the machine tool, the spindle frequency and the tool. Then, we set up an experimental study in order to evaluate the influence of the identified sources of vibrations on surface quality and on the vibrations measured on the cutting tool. Finally we studied the correlations between the vibrations and the surface quality obtained by superfinishing turnin