Papers by Solomon Phokobye
MM Science Journal, Nov 13, 2019
The measurement of cutting forces using highly sensitive piezoelectric force sensors is significa... more The measurement of cutting forces using highly sensitive piezoelectric force sensors is significant in the optimization of the machining process. In this study, the modelling and optimization of the cutting forces during the milling process of Ti6Al4V was carried out using the Response Surface Methodology (RSM) and the dynamometer. The ranges of the process parameters are: cutting speed (250-280 mm/min), feed per tooth (0.06-0.24 mm) and axial depth of cut (0.30-3.0 mm) are varied over four levels while cutting force serves as the response of the designed experiment. The physical experiments were carried out using a DMU80monoBLOCK Deckel Maho 5-axis CNC milling. Three sets of 2-flute, 10 mm corner radius mills was used for the machining operation. A solid rectangular work piece of Ti6Al4V was screwed to the stationary dynamometer (KISTLER 9257A 8-Channel Summation of Type 5001A Multichannel Amplifier) mounted directly to the machine table. Milling operations were performed using different cutting parameters of cutting speed, feed per tooth and depth of cut and data were collected through Data Acquisition (DAQ) connected to the computer. The numerical experiment produced a mathematical model for predicting the values of the cutting forces as a function of the independent process parameters while the physical experiment revealed that the piezoelectric sensor is highly sensitive to variations in the values of the cutting force.
Procedia CIRP, 2019
In today's business environment, the trend towards more product variety and customization is unbr... more In today's business environment, the trend towards more product variety and customization is unbroken. Due to this development, the need of agile and reconfigurable production systems emerged to cope with various products and product families. To design and optimize production systems as well as to choose the optimal product matches, product analysis methods are needed. Indeed, most of the known methods aim to analyze a product or one product family on the physical level. Different product families, however, may differ largely in terms of the number and nature of components. This fact impedes an efficient comparison and choice of appropriate product family combinations for the production system. A new methodology is proposed to analyze existing products in view of their functional and physical architecture. The aim is to cluster these products in new assembly oriented product families for the optimization of existing assembly lines and the creation of future reconfigurable assembly systems. Based on Datum Flow Chain, the physical structure of the products is analyzed. Functional subassemblies are identified, and a functional analysis is performed. Moreover, a hybrid functional and physical architecture graph (HyFPAG) is the output which depicts the similarity between product families by providing design support to both, production system planners and product designers. An illustrative example of a nail-clipper is used to explain the proposed methodology. An industrial case study on two product families of steering columns of thyssenkrupp Presta France is then carried out to give a first industrial evaluation of the proposed approach.
The International Journal of Advanced Manufacturing Technology, Aug 18, 2022
The efficiency of machining operation is partly a function of the cutting parameters, such as the... more The efficiency of machining operation is partly a function of the cutting parameters, such as the: cutting speed, depth of cut and cutting feed rate. With an effective cutting performance of any cutting tool, manufacturing industries will remain competitive and hence, strive to meet the dynamic service and functional requirements expected of the material. Hence, the purpose of this research is to experimentally perform a comparative analysis of the cutting performances of SiAlON, a ceramic alloy consisting of the elements: Silicon, Aluminium, Oxygen and Nitrogen, Cubic Boron Nitride (CBN) and Carbide cutting tools, during a titanium machining process. A face milling operation was performed on a computer numerical control (CNC) milling machine from these three different types of cutting tools, for the determination of the: cutting forces, cutting temperatures, cutting vibrations produced and the surface roughness, achieved during the machining of titanium (Ti-6Aℓ-4V) alloy. The Respo...
The International Journal of Advanced Manufacturing Technology
MM Science Journal, 2019
The measurement of cutting forces using highly sensitive piezoelectric force sensors is significa... more The measurement of cutting forces using highly sensitive piezoelectric force sensors is significant in the optimization of the machining process. In this study, the modelling and optimization of the cutting forces during the milling process of Ti6Al4V was carried out using the Response Surface Methodology (RSM) and the dynamometer. The ranges of the process parameters are: cutting speed (250-280 mm/min), feed per tooth (0.06-0.24 mm) and axial depth of cut (0.30-3.0 mm) are varied over four levels while cutting force serves as the response of the designed experiment. The physical experiments were carried out using a DMU80monoBLOCK Deckel Maho 5-axis CNC milling. Three sets of 2-flute, 10 mm corner radius mills was used for the machining operation. A solid rectangular work piece of Ti6Al4V was screwed to the stationary dynamometer (KISTLER 9257A 8-Channel Summation of Type 5001A Multichannel Amplifier) mounted directly to the machine table. Milling operations were performed using different cutting parameters of cutting speed, feed per tooth and depth of cut and data were collected through Data Acquisition (DAQ) connected to the computer. The numerical experiment produced a mathematical model for predicting the values of the cutting forces as a function of the independent process parameters while the physical experiment revealed that the piezoelectric sensor is highly sensitive to variations in the values of the cutting force.
Procedia CIRP, 2019
In today's business environment, the trend towards more product variety and customization is unbr... more In today's business environment, the trend towards more product variety and customization is unbroken. Due to this development, the need of agile and reconfigurable production systems emerged to cope with various products and product families. To design and optimize production systems as well as to choose the optimal product matches, product analysis methods are needed. Indeed, most of the known methods aim to analyze a product or one product family on the physical level. Different product families, however, may differ largely in terms of the number and nature of components. This fact impedes an efficient comparison and choice of appropriate product family combinations for the production system. A new methodology is proposed to analyze existing products in view of their functional and physical architecture. The aim is to cluster these products in new assembly oriented product families for the optimization of existing assembly lines and the creation of future reconfigurable assembly systems. Based on Datum Flow Chain, the physical structure of the products is analyzed. Functional subassemblies are identified, and a functional analysis is performed. Moreover, a hybrid functional and physical architecture graph (HyFPAG) is the output which depicts the similarity between product families by providing design support to both, production system planners and product designers. An illustrative example of a nail-clipper is used to explain the proposed methodology. An industrial case study on two product families of steering columns of thyssenkrupp Presta France is then carried out to give a first industrial evaluation of the proposed approach.
The International Journal of Advanced Manufacturing Technology
2020 IEEE 11th International Conference on Mechanical and Intelligent Manufacturing Technologies (ICMIMT), 2020
Titanium alloy (Ti6Al4V) possesses excellent mechanical properties, but its machinability at high... more Titanium alloy (Ti6Al4V) possesses excellent mechanical properties, but its machinability at high temperature and speed often lead to vibration and subsequently chatter during machining operations. In this work, the modelling and optimization of the cutting parameters for the milling operations of titanium alloy Ti6Al4V was carried out. The numerical experiment was conducted using the Response Surface Methodology (RSM). The process parameters considered include; the maximum chip thickness (0.1-0.2 mm), cutting speed (29000-34000 mm/min) and feed per tooth (0.14 - 0.28 mm). These process parameters were varied over different levels. The physical experiment was conducted on a DMU80monoBLOCK Deckel Maho 5-axis CNC milling with the stationary dynamometer (KISTLER 9257A 8-Channel Summation of Type 5001A Multichannel Amplifier) mounted directly to the machine table with the titanium alloy screwed to it. The response of the experiment; cutting force for each of the experimental trial was collected through the Data Acquisition System (DAS) of the Kistler Dynamometer. The results obtained indicate significant model terms which implies that the developed model is suitable for predictive purpose and that the process parameters can significantly influence the magnitude of the cutting forces.
The right combination of the process parameters that will bring about effective milling operation... more The right combination of the process parameters that will bring about effective milling operation of titanium alloy (Ti6Al4V) is a critical decision which requires scientific basis for its justification. In this work, the Taguchi method involving four factors and three levels was employed for the process optimization during the milling operation of Ti6Al4V. The physical experiments were performed using the DMU80monoBLOCK Deckel Maho 5-axis CNC milling while a stationary dynamometer (KISTLER 9257A 8-Channel Summation of Type 5001A Multichannel Amplifier) was employed for data acquisition in real time. The range of the process parameters employed include: cutting speed (250000-270000 mm/min), feed per tooth (0.02-0.05 mm), axial depth of cut (0.50-3.0 mm) and radial depth of cut (0.06-5.00 mm). Taking the rate of material removal as the response of both the numerical and physical experiments, the statistical analysis of the results obtained produced a mathematical model for the optimi...
2020 IEEE 11th International Conference on Mechanical and Intelligent Manufacturing Technologies (ICMIMT), 2020
Titanium alloy (Ti6Al4V) possesses excellent mechanical properties, but its machinability at high... more Titanium alloy (Ti6Al4V) possesses excellent mechanical properties, but its machinability at high temperature and speed often lead to vibration and subsequently chatter during machining operations. In this work, the modelling and optimization of the cutting parameters for the milling operations of titanium alloy Ti6Al4V was carried out. The numerical experiment was conducted using the Response Surface Methodology (RSM). The process parameters considered include; the maximum chip thickness (0.1-0.2 mm), cutting speed (29000-34000 mm/min) and feed per tooth (0.14 - 0.28 mm). These process parameters were varied over different levels. The physical experiment was conducted on a DMU80monoBLOCK Deckel Maho 5-axis CNC milling with the stationary dynamometer (KISTLER 9257A 8-Channel Summation of Type 5001A Multichannel Amplifier) mounted directly to the machine table with the titanium alloy screwed to it. The response of the experiment; cutting force for each of the experimental trial was c...
International Journal of Mechanical Engineering and Robotics Research
The quality of a product is partly a function of its surface finish. This work considers the inve... more The quality of a product is partly a function of its surface finish. This work considers the investigation of the surface roughness of a hardened tool steel during face milling operation. The design of experiment was carried out using the Taguchi approach and this was validated via physical experimentations. The physical experiments were carried out on Deckel Maho milling machine using a SANDVIK indexable cutting tool (R390-11 T3 08M-PM 1010) on a 2379 tool steel for press tools. The process parameters considered were the cutting speed, feed per tooth and depth of cut under different cutting conditions, which includes air-cooling and soluble oil cooling. The results obtained indicate that cutting operations under soluble oil cooling condition gave a better surface finish as compared to the cutting operations under air-cooling. The optimum combination of the process parameters, which produced the least surface roughness under the air cooling and soluble oil cooling conditions, are: cutting speed (125 m/min), feed per tooth (0.08 mm) and depth of cut (0.5 mm). It is envisaged that this study will assist machinists in the process design of machining operations for the development of products with good surface integrity.
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Papers by Solomon Phokobye