Mohamed Slamani - Academia.edu (original) (raw)

Papers by Mohamed Slamani

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Composite material consumption is booming and is expected to increase exponentially in many indus... more Composite material consumption is booming and is expected to increase exponentially in many industrial applications such as aerospace, automotive, marine and defense. However, in most cases, composite products require further processing before they can be used or assembled. Machining of composite materials is extremely difficult due to their anisotropic and non-homogeneous structure. This paper provides a comprehensive review of the literature on composite materials and their machining processes, such as turning, milling and drilling. Damage related to these processes is also discussed. The paper is divided into seven main parts; the first, second and third parts give a brief overview of composite materials, reinforcements used in composite materials and composite manufacturing methods, respectively. The fourth part deals with post-processing machining operations, while the fifth, sixth and seventh parts are devoted to the machining of carbon fiber reinforced polymer composite, glas...

The International Journal of Advanced Manufacturing Technology, 2022

International Journal of Material Forming, 2021

Physica A: Statistical Mechanics and its Applications, 2021

Abstract Skin panels are one of the most important components constituting the aircraft structure... more Abstract Skin panels are one of the most important components constituting the aircraft structures such as wing and fuselage sections. These thin-walled components were produced from 2024-T3 aluminum alloys and many pockets were usually created in these panels by chemical milling process for weight reduction purpose. However, this process is time consuming due to its slow metal removal rate, its health hazard and its severe significant environmental impact. End-milling could provide an excellent base for creating the panel pockets and maintain the required precision. Nevertheless, maintaining a comparable quality between the two processes is quite challenging due to the dynamic nature of the cutting process and the heat generating during machining. Furthermore, an overheating in the cutting zone generally induces structural variations of the material texture, involving residual stresses and reduces stiffness which leads to damages in the machined panels. In this paper, the effect of cutting conditions on heat generation was investigated experimentally based on Taguchi and full factorial design techniques. A quantitative and qualitative statistical analysis is used to identify relationships among heat generation and process parameters, heat generation and cutting region and finally, heat generation and machining operation. The results showed that the proposed approach can successfully detects the significance or non-significance of the temperature variation between different cutting zones and machining operations.

The International Journal of Advanced Manufacturing Technology, 2021

In the manufacturing industry, there are several types of parts of complex shapes owning various ... more In the manufacturing industry, there are several types of parts of complex shapes owning various functions. The turbine blades (buckets and vanes) are one of the most important components in gas turbines. However, these blades have complex shapes and irregular surface curvature which make them difficult to machine. Production of such kind of parts is so complicated and requires a high control of machining process, advanced CNC programming, innovative tools, and special fixtures allowing to maintain exactly and rigidly in a unique position of the part during machining. In order to enhance productivity and reduce operation time, thereby increasing parts quality, the machining fixture has to fulfill several requirements such as allowing a correct location with security and repeatability of the workpiece as well as maintaining conformity and interchangeability of the machined parts. This paper addresses the challenge of machining complex geometry parts by development and realization of a dedicated machining fixture (MF) for holding a mobile blade of a gas turbine. The first novelty of this work is in the application of the Pluckerian coordinates method for choosing the locator’s placement of complex-shaped parts. The choice of the locator’s placement during the design process of the fixture is performed based on the maximization of the determinant and minimization of the condition number of the locator matrix (information matrix). The second novelty is in the optimization approach used. The last novelty is in the developed and fabricated machining fixture. The performance of the developed fixture in terms of localization repeatability is evaluated based on the small displacement torsor (SDT) concept. Results show the validity of the developed fixture.

Measurement, 2019

Please cite this article as: M. Slamani, J-F. Chatelain, Kriging versus Bezier and regression met... more Please cite this article as: M. Slamani, J-F. Chatelain, Kriging versus Bezier and regression methods for modeling and prediction of cutting force and surface roughness during high speed edge trimming of Carbon fiber reinforced polymers, Measurement (2019), doi:

Journal of Manufacturing Processes, 2019

In this paper, an experimental approach has been developed and implemented to assess the capabili... more In this paper, an experimental approach has been developed and implemented to assess the capability of a heavyduty six-axis robot to machine CFRP parts. A simple technique based on fast Fourier transformation (FFT) analysis is devised and applied to identify the relevant sources of errors during high speed robotic trimming. A strategy based on statistical tests was investigated to quantify and predict the relative contribution of the cutting parameters and machining strategy on the cutting force components, path deviation and heat dissipation during machining. Machining quality was quantified in terms of surface damage, delamination and workpiece form errors. Statistical analysis of the experimental results reveals a strong dependence between parts accuracy, cutting direction, and robot position. An experimental model was developed to represent and predict the cutting force and the path deviation during machining. An excellent error prediction capability was observed. Results show also that the temperature in the cutting zone increased with the increase in feed rate. It was found that at high feed rate and high cutting velocity, delamination and workpiece form errors were the most sources of error affecting the accuracy of the machined parts. Results show also that the surface quality was significantly affected by the presence of many empties grooves due to fibers pull out. Loosely speaking, various factors are responsible for the lack of

Transactions of the Canadian Society for Mechanical Engineering, 2012

Two important aspects of the performance of a servo system, tracking errors and contour errors, s... more Two important aspects of the performance of a servo system, tracking errors and contour errors, significantly affect the accuracy of industrial robots under high-speed motion. Careful tuning of the control parameters in a servo system is essential, if the risk of severe structural vibration and a large contouring error is to be avoided. In this paper, we present an overview of a method to diagnose contouring errors caused by the servo control system of an ABB IRB 1600 industrial robot by measuring the robot’s motion accuracy in a Cartesian circular shape using a double ballbar (DBB) measurement instrument. Tests were carried out at different TCP (tool centre-point) speed and trajectory radii to investigate the main sources of errors that affect circular contouring accuracy. Results show that radius size errors and out-of-roundness are significant. A simple experimental model based on statistical tests was also developed to represent and predict the radius size error. The model was e...

International Journal of Material Forming, 2018

CVD diamond-coated carbide tools could provide an economical alternative for trimming CFRPs compo... more CVD diamond-coated carbide tools could provide an economical alternative for trimming CFRPs components compared to their PCD tools counterpart. Nevertheless, there are still some technical issues to understand related to wear resistance and surface quality. In this work, a CVD tool with six straight flutes was used to investigate the relationship between surface roughness, surface damage, tool wear, cutting force and cutting parameters during the high speed trimming of CFRPs. Statistical techniques for identifying and selecting the best cutting conditions for CVD tool are developed. In terms of tool wear, results show that the best operational condition to minimize the tool wear is achieved at lower feed rates and higher cutting speeds. Experimental results show also that a 0°ply orientation represents the worst case and produces the maximum tool wear. Furthermore, a strong correlation between the feed force and the tool wear was observed. It was found that the surface roughness decreases as a reciprocal function of cutting length. This decrease was due to the matrix burning/sticking and the thermal damage related to the low thermal conductivity of CFRP. In such situation, R a becomes inappropriate indicator for roughness evaluation. On the other hand, it wasn't seen any type of delamination or fiber pull-out on the trimmed surface of all coupons for the three tool life tests. Accordingly, delamination can be avoided using high fixture rigidity, high quality of CFRP laminates, a suitable cutting tool and stable operational conditions.

Robotics and Computer-Integrated Manufacturing, 2016

This paper proposes an experimental approach for evaluating the surface roughness of the CFRP par... more This paper proposes an experimental approach for evaluating the surface roughness of the CFRP parts produced by high speed CNC trimming and high speed robotic trimming under various cutting conditions. A comparison is made between the surface roughnesses obtained by the two processes. The results obtained show that, the measured profiles obtained from high speed robotic trimming are dominated by a large trajectory deviation, as compared to machine tool trimming results. After the trajectory deviation effect is discounted, the results show that for the þ45°ply orientation, the surface quality obtained through high speed robotic trimming is similar to what is obtained with the CNC machine. Furthermore, a significant relationship was observed between the surface quality and the ply orientation, whatever the machining process and the cutting conditions employed. The À 45°ply orientation represents the worst case in terms of surface roughness, whatever the machining process. It is 4 times higher compared with that of þ45°ply orientations, The results also show that the effect of cutting conditions on surface quality is significant for both machining processes tested.

Industrial Robot: An International Journal, 2015

Purpose – The purpose of this paper is to present a technique for assessing and comparing the sta... more Purpose – The purpose of this paper is to present a technique for assessing and comparing the static and dynamic performance of three different models of small six-axis industrial robots using a Renishaw XL80 laser interferometer system, a FARO ION laser tracker and a Renishaw QC20-W telescoping ballbar. Design/methodology/approach – Specific test methods are proposed in this work, and each robot has been measured in a similar area of its working envelope. The laser interferometer measurement instrument is used to assess the static positioning performance along three linear and orthogonal paths. The laser tracker is used to assess the contouring performance at different tool center point (TCP) speeds along a triangular tool path, whereas the telescoping ballbar is used to assess the dynamic positioning performance for circular paths at different TCP speeds and trajectory radii. Findings – It is found that the tested robots behave differently, and that the static accuracy of these no...

Proceedings of the 12th International Conference on Informatics in Control, Automation and Robotics, 2015

Thanks to their adaptability, programmability, high dexterity and good maneuverability, industria... more Thanks to their adaptability, programmability, high dexterity and good maneuverability, industrial robots offer more cutting-edge and lower-cost than machine tools to bring molded Carbon Fibre Reinforced Polymers (CFRPs) parts to their final shapes and sizes. However, the quality of CFRP parts obtained with robotic machining must be comparable to that obtained with a CNC machine. In addition, the robot itself has to be very stiff and accurate to provide the same consistency and accuracy as their machine tool counterparts. If the robot is not sufficiently stiff, chatter, overall vibrations and deviations in shape and position of the workpieces will occur. Furthermore, during robotic machining of Carbon Fibre Reinforced Polymer, the anisotropic and highly abrasive nature of CFRPs combined with the higher cutting forces and the lower stiffness of the robot, lead to numerous machining problems. Therefore, robotic machining of CFRPs stills a big challenge and need further research. In this position paper, a methodology has been developed and implemented to identify, understand and quantify the machining errors that can alter parts accuracy during high speed robotic trimming of CFRPs.

ABSTRACT The combination of low thermal conductivity and highly abrasive nature of Carbon Fibre R... more ABSTRACT The combination of low thermal conductivity and highly abrasive nature of Carbon Fibre Reinforced Polymers (CFRPs) leads to rapid tool wear and numerous machining problems. This paper presents the development of tool wear and cutting force prediction models in the high speed trimming of CFRPs. A 3/8 inch diameter CVD diamond-coated carbide tool with six straight flutes was used to trim 24-ply carbon fibre laminates. Cutting speeds ranging from 200 m/min to 400 m/min and feed rates ranging from 1524 mm/min to 4064 mm/min were used in the experiments. Exponential models were adjusted to predict tool wear and cutting force for different values of cutting speed, feed and cutting length. The ANOVA approach was used to test the overall significance of the models by applying F-tests. The results obtained show that the exponential model is capable of accurately predicting the cutting force and tool wear under the conditions studied.

Measurement, 2015

In this study, the combined effects of machining parameters on cutting force components during hi... more In this study, the combined effects of machining parameters on cutting force components during high speed robotic trimming of CFRPs were experimentally investigated. A statistical technique based on the evaluation of the rank and the condition number of the observation matrix followed by the backward elimination approach was used for selecting the most important variables of the models. The developed models were then used to predict the cutting force components for different values of cutting speed, feed and robot configuration. Outcomes from the models were analysed and compared. A very good agreement with experimental data was achieved. Furthermore, results show that the amplitude for the normal force is higher than that for the feed force. The feed rate exhibits greater influence on cutting force components as compared to the cutting speed and robot configuration. The two-level interaction effect of the feed, cutting speed and robot configuration are also found significant.

Machinability of Fibre-Reinforced Plastics, 2015

International Journal of Material Forming, 2014

ABSTRACT Because of the low thermal conductivity of Carbon Fibre Reinforced Polymers (CFRPs) duri... more ABSTRACT Because of the low thermal conductivity of Carbon Fibre Reinforced Polymers (CFRPs) during high speed-trimming, cutting forces and tool wear significantly increase the temperature at the contact zone, which is then completely transferred to the cutting tool and exceeds the permitted thermal stability limit of the cutting material. This then leads to a drastic reduction of the tool life, thermal damage, poor quality, and in some cases, rejection of machined parts. This paper presents the development of tool wear and cutting force prediction models in the trimming of CFRPs. A 3/8 in. diameter CVD diamond-coated carbide tool with six straight flutes was used to trim 24-ply carbon fibre laminates. The results obtained using a scanning electron microscope (SEM) showed increasing defect rates with increased tool wear. Two models were adjusted to predict tool wear and cutting force for different values of cutting speed, feed and cutting length. One of them is a multiplicative statistical model, and the other, an exponential model. Outcomes from the two models were analysed and compared. The ANOVA approach was also used to test the overall significance of the models by applying F-tests. The results obtained show that the exponential model is better capable of accurately predicting the cutting force and tool wear under the conditions studied. To enhance the prediction accuracy of the tool wear model, the cutting force was added as a variable in the tool wear model. Results show that the enhanced multiplicative model provided higher predictive capabilities than the exponential model.