H. Kishawy | University of Ontario Institute of Technology (original) (raw)

Papers by H. Kishawy

Journal of Manufacturing Science and Engineering, 2004

In this paper a model is developed to analyze heat transfer and temperature distribution resultin... more In this paper a model is developed to analyze heat transfer and temperature distribution resulting during machining with rotary tools. The presented model is based on a finite-volume discretization approach applied to a general conservation of energy statement for the rotary tool and chip during machining. The tool rotational speed is modeled and its effect on the heat partitioning between the tool and the chip is investigated. The model is also used to examine the influence of tool speed on the radial temperature distribution on the tool rake face. A comparison between the predicted and previously measured temperature data shows good agreement. In general the results show that the tool-chip partitioning is influenced dramatically by increasing the tool rotational speed at low to moderate levels of tool speed. Also, there is an optimum tool rotational speed at which further increase in the tool rotational speed increases the average tool temperature.

Procedia CIRP, 2014

Metal matrix composites (MMCs), as a new generation of materials; have proven to be viable materi... more Metal matrix composites (MMCs), as a new generation of materials; have proven to be viable materials in various industrial fields such as biomedical and aerospace. In order to achieve a valuable modification in various properties of materials, metallic matrices are reinforced with additional phases based on the chemical and/or physical properties required in the in-service operating conditions. The presence of the reinforcements in MMCs improves the physical, mechanical and thermal properties of the composite; however it induces significant issues in the domain of machining, such as high tool wear and inferior surface finish. The interaction between the tool and abrasive hard reinforcing particles induces complex deformation behaviour in the MMC structure. Sever tool wear is technically the most important drawback of machining MMCs.

Metal matrix composites (MMCs), as a new generation of materials; have proven to be viable materi... more Metal matrix composites (MMCs), as a new generation of materials; have proven to be viable materials in various industrial fields such as biomedical and aerospace. In order to achieve a valuable modification in various properties of materials, metallic matrices are reinforced with additional phases based on the chemical and/or physical properties required in the in-service operating conditions. The presence of the reinforcements in MMCs improves the physical, mechanical and thermal properties of the composite; however it induces significant issues in the domain of machining, such as high tool wear and inferior surface finish. The interaction between the tool and abrasive hard reinforcing particles induces complex deformation behaviour in the MMC structure. Sever tool wear is technically the most important drawback of machining MMCs.

Machining Technology for Composite Materials, 2012

Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture, 2015

Little practical results are known about the cutting tool optimal replacement time, specifically ... more Little practical results are known about the cutting tool optimal replacement time, specifically for machining of composite materials. Due to the fact that tool failure represents about 20% of machine down-time, and due to the high cost of machining, in particular when the work piece's material is very expensive, optimization of tool replacement time is thus fundamental. Finding the optimal replacement time has also positive impact on product quality in terms of dimensions and surface finish. In this article, two new contributions to research on tool replacement are introduced. First, tool replacement mathematical models are proposed. These models are used in order to find the optimal time to tool replacement when the tool is used under variable machining conditions, namely, the cutting speed and the feed rate. Proportional hazards models are used to find an optimal replacement function. Second, this model is obtained during turning titanium metal matrix composites. These composites are a new generation of materials which have proven to be viable in various industrial fields such as biomedical and aerospace, and they are very expensive. Experimental data are obtained and used in order to develop and to validate the proportional hazards models, which are then used to find the optimal replacement conditions.

In machining of composite materials, little research has been conducted in the area of optimal re... more In machining of composite materials, little research has been conducted in the area of optimal replacement time of the cutting tool in terms of cost and availability. Due to the fact that tool failure represents about 20% of machine down-time, and due to the high cost of machining, optimization of tool replacement time is thus fundamental. Finding the optimal replacement time has also positive impact on product quality in terms of dimensions, and surface finish.

properties over titanium alloys. Therefore, this material has recently been used in several appli... more properties over titanium alloys. Therefore, this material has recently been used in several applications in the aerospace and automotive industries. Although the TiMMC parts are made near net shape, a finish machining operation is often necessary to achieve the required surface finish and dimensional accuracy. In general, MMCs have been known to be difficult to cut materials, since the added ceramic hard particles are very abrasive and limit the tool life. Titanium alloys are also known to be problematic in machining; therefore, TiMMC combines both machining problems associated with MMCs and titanium alloys. Since data on the machinability of TiMMC is very limited in the open literature, this paper focuses on comparing the performance of different tools under different cutting parameters in order to find the optimum cutting conditions within the constraints of maximum surface integrity and tool life. This research revealed that Poly-Crystalline-Diamond (PCD) tools substantially outperform coated carbide tools. Moreover, chip formation has been carefully studied to understand the interaction of the added Titanium Carbide (TiC) particles with the cutting tool. Contrary to other materials, cutting of TiMMC at higher speeds was found to be more advantageous and resulted in a higher tool life. Analysis of the chip morphology also revealed that the chip formation at high speeds is clearly different from that at lower speeds, suggesting a different cutting mechanism.

This paper evaluates the hole quality on Al 6061 aluminum alloy using peck drilling process. Spec... more This paper evaluates the hole quality on Al 6061 aluminum alloy using peck drilling process. Specimens were drilled under dry conditions with HSS drill of 10 mm diameter. Peck drilling experiments were conducted in three steps of 10 mm each. Hole quality is checked by measuring the roughness (Ra) of generated surfaces. This roughness analysis indicates that new step in peck drilling has strong influence on surface roughness of previously drilled step. This work also suggests that step length and no of steps are important influential factors for surface roughness in peck drilling.

Procedia CIRP, 2013

ABSTRACT The Outstanding characteristics of titanium metal matrix composites (Ti-MMCs) have broug... more ABSTRACT The Outstanding characteristics of titanium metal matrix composites (Ti-MMCs) have brought them up as promising materials in different industries, such as aerospace and biomedical. They exhibit high mechanical and physical properties, in addition to their low weight, high stiffness and high wear resistance. The presence of the ceramic reinforcements in a metallic matrix further contributes to these preferable properties. However, the high abrasive nature of the ceramic particles limits greatly the machinability of this class of material, as they induce significant tool wear and poor surface finish. In this study an attempt is made to find the optimum cutting conditions in terms of minimizing the tool wear and surface roughness during machining Ti-MMCs. Meta-modeling optimization in performed to achieve the goal.

Procedia CIRP, 2014

Metal matrix composites (MMCs), as a new generation of materials; have proven to be viable materi... more Metal matrix composites (MMCs), as a new generation of materials; have proven to be viable materials in various industrial fields such as biomedical and aerospace. In order to achieve a valuable modification in various properties of materials, metallic matrices are reinforced with additional phases based on the chemical and/or physical properties required in the in-service operating conditions. The presence of the reinforcements in MMCs improves the physical, mechanical and thermal properties of the composite; however it induces significant issues in the domain of machining, such as high tool wear and inferior surface finish. The interaction between the tool and abrasive hard reinforcing particles induces complex deformation behaviour in the MMC structure. Sever tool wear is technically the most important drawback of machining MMCs.

In this paper, an attempt is made to evaluate the self-propelled rotary carbide tool performance ... more In this paper, an attempt is made to evaluate the self-propelled rotary carbide tool performance during machining hardened steel. Although several models were developed and used to evaluate the tool wear in conventional tools, there were no attempts in open literature for modeling the progress of tool wear when using the self-propelled rotary tools. Flank wear model for self-propelled rotary cutting tools is developed based on the work-tool geometric interaction and the empirical function. A set of cutting tests were carried out on the AISI 4340 steel with hardness of 54-56 HRC under different cutting speeds and feeds. The progress of tool wear was recorded under different interval of time. A genetic algorithm was developed to identify the constants in the proposed model. The comparison of measured and predicted flank wear showed that the developed model is capable of predicting the rate of rotary tool flank wear progression.

Metal matrix composites (MMCs) are new generation engineering materials that possess superior phy... more Metal matrix composites (MMCs) are new generation engineering materials that possess superior physical and mechanical properties compared to non-reinforced alloys. However, the presence of abrasive ceramic reinforcements in the ductile matrix causes severe tool wear and premature tool failure. Flank wear was found to be the dominant wear mode while the main wear mechanism was abrasion. Analysis of the cutting tools using scanning electron microscopy (SEM) has shown that both two-body and three-body abrasion are operational during machining of MMCs. In this paper, a methodology for predicting the tool flank wear progression during bar turning of MMCs is presented. In the proposed model, the wear volume due to two-body and three-body abrasion mechanisms was formulated. In addition, the flank wear rate was quantified by considering the tool geometry in three dimensional (3D) turning. The main objective of this paper is to investigate the contribution of two-body and three-body abrasion towards the tool wear volume during cutting MMCs.

This paper presents an analytical model for the prediction of tool flank wear progression during ... more This paper presents an analytical model for the prediction of tool flank wear progression during bar turning of particulate reinforced metal matrix composites. In this paper, a methodology for analytically predicting the wear progression as function of tool/workpiece properties and cutting parameters is presented. According to this approach, the wear volume due to two body and three body abrasion is

CIRP Annals - Manufacturing Technology, 2004

The machining of metal matrix composite (MMC) presents a significant challenge to the industry. T... more The machining of metal matrix composite (MMC) presents a significant challenge to the industry. The hard and abrasive nature of the reinforcement causes rapid tool wear and high machining cost. Cracking and debonding of the reinforcement particles are the significant damage modes that directly affect the tool performance. This paper presents, an energy based analytical force model that has been

Journal of Manufacturing Science and Engineering, 2004

In this paper a model is developed to analyze heat transfer and temperature distribution resultin... more In this paper a model is developed to analyze heat transfer and temperature distribution resulting during machining with rotary tools. The presented model is based on a finite-volume discretization approach applied to a general conservation of energy statement for the rotary tool and chip during machining. The tool rotational speed is modeled and its effect on the heat partitioning between the tool and the chip is investigated. The model is also used to examine the influence of tool speed on the radial temperature distribution on the tool rake face. A comparison between the predicted and previously measured temperature data shows good agreement. In general the results show that the tool-chip partitioning is influenced dramatically by increasing the tool rotational speed at low to moderate levels of tool speed. Also, there is an optimum tool rotational speed at which further increase in the tool rotational speed increases the average tool temperature.

Procedia CIRP, 2014

Metal matrix composites (MMCs), as a new generation of materials; have proven to be viable materi... more Metal matrix composites (MMCs), as a new generation of materials; have proven to be viable materials in various industrial fields such as biomedical and aerospace. In order to achieve a valuable modification in various properties of materials, metallic matrices are reinforced with additional phases based on the chemical and/or physical properties required in the in-service operating conditions. The presence of the reinforcements in MMCs improves the physical, mechanical and thermal properties of the composite; however it induces significant issues in the domain of machining, such as high tool wear and inferior surface finish. The interaction between the tool and abrasive hard reinforcing particles induces complex deformation behaviour in the MMC structure. Sever tool wear is technically the most important drawback of machining MMCs.

Metal matrix composites (MMCs), as a new generation of materials; have proven to be viable materi... more Metal matrix composites (MMCs), as a new generation of materials; have proven to be viable materials in various industrial fields such as biomedical and aerospace. In order to achieve a valuable modification in various properties of materials, metallic matrices are reinforced with additional phases based on the chemical and/or physical properties required in the in-service operating conditions. The presence of the reinforcements in MMCs improves the physical, mechanical and thermal properties of the composite; however it induces significant issues in the domain of machining, such as high tool wear and inferior surface finish. The interaction between the tool and abrasive hard reinforcing particles induces complex deformation behaviour in the MMC structure. Sever tool wear is technically the most important drawback of machining MMCs.

Machining Technology for Composite Materials, 2012

Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture, 2015

Little practical results are known about the cutting tool optimal replacement time, specifically ... more Little practical results are known about the cutting tool optimal replacement time, specifically for machining of composite materials. Due to the fact that tool failure represents about 20% of machine down-time, and due to the high cost of machining, in particular when the work piece's material is very expensive, optimization of tool replacement time is thus fundamental. Finding the optimal replacement time has also positive impact on product quality in terms of dimensions and surface finish. In this article, two new contributions to research on tool replacement are introduced. First, tool replacement mathematical models are proposed. These models are used in order to find the optimal time to tool replacement when the tool is used under variable machining conditions, namely, the cutting speed and the feed rate. Proportional hazards models are used to find an optimal replacement function. Second, this model is obtained during turning titanium metal matrix composites. These composites are a new generation of materials which have proven to be viable in various industrial fields such as biomedical and aerospace, and they are very expensive. Experimental data are obtained and used in order to develop and to validate the proportional hazards models, which are then used to find the optimal replacement conditions.

In machining of composite materials, little research has been conducted in the area of optimal re... more In machining of composite materials, little research has been conducted in the area of optimal replacement time of the cutting tool in terms of cost and availability. Due to the fact that tool failure represents about 20% of machine down-time, and due to the high cost of machining, optimization of tool replacement time is thus fundamental. Finding the optimal replacement time has also positive impact on product quality in terms of dimensions, and surface finish.

properties over titanium alloys. Therefore, this material has recently been used in several appli... more properties over titanium alloys. Therefore, this material has recently been used in several applications in the aerospace and automotive industries. Although the TiMMC parts are made near net shape, a finish machining operation is often necessary to achieve the required surface finish and dimensional accuracy. In general, MMCs have been known to be difficult to cut materials, since the added ceramic hard particles are very abrasive and limit the tool life. Titanium alloys are also known to be problematic in machining; therefore, TiMMC combines both machining problems associated with MMCs and titanium alloys. Since data on the machinability of TiMMC is very limited in the open literature, this paper focuses on comparing the performance of different tools under different cutting parameters in order to find the optimum cutting conditions within the constraints of maximum surface integrity and tool life. This research revealed that Poly-Crystalline-Diamond (PCD) tools substantially outperform coated carbide tools. Moreover, chip formation has been carefully studied to understand the interaction of the added Titanium Carbide (TiC) particles with the cutting tool. Contrary to other materials, cutting of TiMMC at higher speeds was found to be more advantageous and resulted in a higher tool life. Analysis of the chip morphology also revealed that the chip formation at high speeds is clearly different from that at lower speeds, suggesting a different cutting mechanism.

This paper evaluates the hole quality on Al 6061 aluminum alloy using peck drilling process. Spec... more This paper evaluates the hole quality on Al 6061 aluminum alloy using peck drilling process. Specimens were drilled under dry conditions with HSS drill of 10 mm diameter. Peck drilling experiments were conducted in three steps of 10 mm each. Hole quality is checked by measuring the roughness (Ra) of generated surfaces. This roughness analysis indicates that new step in peck drilling has strong influence on surface roughness of previously drilled step. This work also suggests that step length and no of steps are important influential factors for surface roughness in peck drilling.

Procedia CIRP, 2013

ABSTRACT The Outstanding characteristics of titanium metal matrix composites (Ti-MMCs) have broug... more ABSTRACT The Outstanding characteristics of titanium metal matrix composites (Ti-MMCs) have brought them up as promising materials in different industries, such as aerospace and biomedical. They exhibit high mechanical and physical properties, in addition to their low weight, high stiffness and high wear resistance. The presence of the ceramic reinforcements in a metallic matrix further contributes to these preferable properties. However, the high abrasive nature of the ceramic particles limits greatly the machinability of this class of material, as they induce significant tool wear and poor surface finish. In this study an attempt is made to find the optimum cutting conditions in terms of minimizing the tool wear and surface roughness during machining Ti-MMCs. Meta-modeling optimization in performed to achieve the goal.

Procedia CIRP, 2014

Metal matrix composites (MMCs), as a new generation of materials; have proven to be viable materi... more Metal matrix composites (MMCs), as a new generation of materials; have proven to be viable materials in various industrial fields such as biomedical and aerospace. In order to achieve a valuable modification in various properties of materials, metallic matrices are reinforced with additional phases based on the chemical and/or physical properties required in the in-service operating conditions. The presence of the reinforcements in MMCs improves the physical, mechanical and thermal properties of the composite; however it induces significant issues in the domain of machining, such as high tool wear and inferior surface finish. The interaction between the tool and abrasive hard reinforcing particles induces complex deformation behaviour in the MMC structure. Sever tool wear is technically the most important drawback of machining MMCs.

In this paper, an attempt is made to evaluate the self-propelled rotary carbide tool performance ... more In this paper, an attempt is made to evaluate the self-propelled rotary carbide tool performance during machining hardened steel. Although several models were developed and used to evaluate the tool wear in conventional tools, there were no attempts in open literature for modeling the progress of tool wear when using the self-propelled rotary tools. Flank wear model for self-propelled rotary cutting tools is developed based on the work-tool geometric interaction and the empirical function. A set of cutting tests were carried out on the AISI 4340 steel with hardness of 54-56 HRC under different cutting speeds and feeds. The progress of tool wear was recorded under different interval of time. A genetic algorithm was developed to identify the constants in the proposed model. The comparison of measured and predicted flank wear showed that the developed model is capable of predicting the rate of rotary tool flank wear progression.

Metal matrix composites (MMCs) are new generation engineering materials that possess superior phy... more Metal matrix composites (MMCs) are new generation engineering materials that possess superior physical and mechanical properties compared to non-reinforced alloys. However, the presence of abrasive ceramic reinforcements in the ductile matrix causes severe tool wear and premature tool failure. Flank wear was found to be the dominant wear mode while the main wear mechanism was abrasion. Analysis of the cutting tools using scanning electron microscopy (SEM) has shown that both two-body and three-body abrasion are operational during machining of MMCs. In this paper, a methodology for predicting the tool flank wear progression during bar turning of MMCs is presented. In the proposed model, the wear volume due to two-body and three-body abrasion mechanisms was formulated. In addition, the flank wear rate was quantified by considering the tool geometry in three dimensional (3D) turning. The main objective of this paper is to investigate the contribution of two-body and three-body abrasion towards the tool wear volume during cutting MMCs.

This paper presents an analytical model for the prediction of tool flank wear progression during ... more This paper presents an analytical model for the prediction of tool flank wear progression during bar turning of particulate reinforced metal matrix composites. In this paper, a methodology for analytically predicting the wear progression as function of tool/workpiece properties and cutting parameters is presented. According to this approach, the wear volume due to two body and three body abrasion is

CIRP Annals - Manufacturing Technology, 2004

The machining of metal matrix composite (MMC) presents a significant challenge to the industry. T... more The machining of metal matrix composite (MMC) presents a significant challenge to the industry. The hard and abrasive nature of the reinforcement causes rapid tool wear and high machining cost. Cracking and debonding of the reinforcement particles are the significant damage modes that directly affect the tool performance. This paper presents, an energy based analytical force model that has been