Publications internationales

2014
(2014), Mathematical modeling for turning on AISI 420 stainless steel using surface response methodology . Journal of Engineering Manufacture, IMechE : SAGE Publications, http://pib.sagepub.com/content/early/2014/04/23/0954405414526385.

Résumé: Authors: L Bouzid, MA Yallese, K Chaoui, T Mabrouki, L Boulanouar. In this study, an attempt has been made to statistically model the relationship between cutting parameters (speed, feed rate and depth of cut), cutting force components (Fx, Fy and Fz) and workpiece absolute surface roughness (Ra). The machining case of a martensitic stainless steel (AISI 420) is considered in a common turning process by means of a chemical vapor deposition–coated carbide tool. A full-factorial design (43) is adopted in order to analyze obtained experimental results via both analysis of variance and response surface methodology techniques. The optimum cutting conditions are achieved using mutually response surface methodology and desirability function approaches while the model adequacy is checked from residual values. The results indicated that the depth of cut is the dominant factor affecting (Fx: 86%, Fy: 58% and Fz: 81%), whereas feed rate is found to be the utmost factor influencing surface roughness behavior (Ra: 81%). In addition, a good agreement between the predicted and measured cutting force components and surface roughness was observed. The results are also validated experimentally by determining errors (Fx: 6.51%, Fy: 4.36%, Fz: 3.59% and Ra: 5.12%). Finally, the ranges for optimal cutting conditions are projected for serial industrial production.

2009
(2009), Hard machining of hardened bearing steel using cubic boron nitride tool. Journal of Materials Processing Technology, UK : Elsevier, http://www.journals.elsevier.com/journal-of-materials-processing-technology/

Résumé: Authors: Mohamed Athmane Yallese, Kamel Chaoui, Nassereddine Zeghib, Lakhdar Boulanouar, Jean-François Rigal. In many cases, hard machining remains an economic alternative for bearing parts fabrication using hardened steels. The aim of this experimental investigation is to establish the behaviour of a CBN tool during hard turning of 100Cr6-tempered steel. Initially, a series of long-duration wear tests is planned to elucidate the cutting speed effects on the various tool wear forms. Then, a second set of experiments is devoted to the study of surface roughness, cutting forces and temperature changes in both the chip and the workpiece. The results show that CBN tool offers a good wear resistance despite the aggressiveness of the 100Cr6 at 60HRC. The major part of the heat generated during machining is mainly dissipated through the chip. Beyond 280 m/min, the machining system becomes unstable and produces significant sparks and vibrations after only a few minutes of work. The optimal productivity of machined chip was recorded at a speed of 120 m/min for an acceptable tool flank wear below 0.4 mm. Beyond this limiting speed, roughness (Ra) is stabilized because of a reduction in the cutting forces at high speeds leading to a stability of the machining system. The controlling parameter over roughness, in such hard turning cases, remains tool advance although ideal models do not describe this effect rationally. Surface quality obtained with CBN tool significantly compared with that of grinding despite an increase in the advance by a factor of 2.5. A relationship between flank wear (VB) and roughness (Ra) is deduced from parametric analysis based on extensive experimental data. Keywords Hard turning; Hardened steel; Cubic boron nitride; Wear; Roughness; Cutting forces

1987
(1987), Effect of residual stress on crack propagation in MDPE pipes. Journal of Materials Science 22 (11), 3873-3879 : Springer Netherlands, http://link.springer.com/article/10.1007/BF01133334

Résumé: K Chaoui, A Chudnovsky, A Moet Crack propagation behaviour in single edge notched specimens prepared from medium-density polyethylene (MDPE) pipe is examined under creep condition. The crack grown from an exterior notch (inbound) initiated faster than that grown from an interior notch (outbound). Subsequently, the outbound crack propagated monotonically to ultimate failure. The inbound crack showed anomalous behaviour involving two arrest stages prior to ultimate failure. The pipe is found to possess substantial residual stresses. The energy release rate for each case was calculated taking into account the respective residual stream distribution. The fact that the rates of crack propagation are not a unique function of the energy release rate indicates that the fracture is also influenced by morphological gradients imposed by processing conditions.

Publications nationales

2014
(2014), Détermination des déformations résiduelles dans les tubes HDPE-100 par la méthode d’enlèvement de co. Communication Science & technology N° 14. : ENPO, http://www.enp-oran.dz/IMG/UserFiles/Images/08.pdf

Résumé: Authors: Hana FADDA, Mounia KADDECHE, Nacera HAMLAOUI, Kamel CHAOUI. This study provides an approach for determining circumferential residual strains and mechanical properties in a high-density polyethylene pipe. The method is based on the preparation of cylindrical envelopes of specific dimensions by machining and the measurement of the obtained deformations as a function of time, after cutting the rings in the longitudinal direction. In order to identify the impact of these residual strains, tensile tests are performed on standard specimens extracted from the pipe wall in L and T directions. The results indicate an evolution of displacements caused by the liberation of internal residual stresses. The calculated stresses are highly compressive on external layers. The mechanical properties measured on the internal layers are largely higher than those of external layers which indicates a difference in morphologies between outer and inner pipe layers imparted by the extrusion process. Keywords: HDPE-100/ Pipe/ Machining/ Residual strain/ Residual stress/ Mechanical properties/ L and T directions/

Communications internationales

2013
(2013), Contribution à l’amélioration du processus d’accréditation national et d’audit des offres de forma. 21ème CFM, Bordeaux, 26-30/08/2013 : AFM, http://documents.irevues.inist.fr/bitstream/handle/2042/52737/a_2ZW46A2Q.pdf

Résumé: Authors: DJAMIL MESSADEG & KAMEL CHAOUI The preparation of the commitment of the Algerian universities in the LMD system dates since 2000. Over the past decade, several approaches have been experienced and current results show a table containing some successes and shortcomings. Today, time of the first doctoral LMD graduates arrived after launching “LMD: 3-5-8”. In this paper, we examine several aspects connected with this issue and discuss in a local context the results after a period of 8 years. First, we discuss the texts and their evolution to see if they have contributed to the initiation of an educational system performance. Secondly, we discuss the objectives (or content where possible) of training offers at different (LMD) levels to observe the adequacy with the labor market demand. We will consider only training opportunities related to the field of Science and Technology at UBM Annaba. Finally, we propose an auditing system taking into account the reality of teaching to preserve quality and improve educational services.