Browsing by Author "Ravi, A.M."

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Comparative Study of Carbide Tools in Turning of High-Chrome White Cast Iron using Hard Turning Methods
(IOP Publishing Ltd, 2021) Ravi, A.M.; Murigendrappa, M.
Thermally enhanced machining (TEM) is a new practice in hard turning of hard materials like White cast iron, Inconel 718 steels etc. Addition of preheating before shear zone improves the elasticity of the material. Before this, Industries invested more capital on toolings and robust machineries/equipments, also it demamed high cost diamond, Cubic boran nitride (CBN) and polyCBN (pCBN) tools. This research paper mainly focusses on the comparative study of machinability characteristics like machining forces and surface roughness of a high hard High chrome white cast iron (HCWCI) when turning with and without the addition preheat using multilayer hard coated carbide (TiC/TiCN/Al2O3). Taguchi technique were used to carryout the experimentational work. The experimental and theoretical investigations are done in different phases in order to derive some of the useful process responses like machining forces, surface roughness etc, and to prove Oxy-LPG aided TEM most appropriate methodology to cut HCWCI. Furthermore derived the suitable conditions at which the coated carbide tools perform better. Hence comparative studies of each process responses are required to arrive to the reasonable conclusions. Â© Published under licence by IOP Publishing Ltd.
Development of internal cooling system in hard turning of annealed HCWCI using carbide tools
(Association of American Publishers, 2025) Ravi, A.M.; Murigendrappa, S.M.
In todayâ€™s manufacturing techniques, hard turning became the most rising technique to cut high hard materials like high chrome white cast iron (HCWCI). The use of Cubic boron nitride (CBN), Polycrystalline Cubic boron nitride (pCBN) and Carbide tools are most appropriate to shear the metals but are uneconomical. These materials are cut in dry condition, which results in lower life and can be enhanced by minimizing the tool temperature. The research study exposes effective tool cooling systems that can improve tool life and machinability characteristics, also proper selection of cutting parameters to control the cutting temperature. The main aim of this paper is to develop an ideal cooling system to control tool temperature, thereby minimizing the tool wear rates and cutting forces. In this research work, experiments were conducted on annealed high chrome white cast iron using carbide inserts. Intricate cavities were made on the toolholder body for easy circulation of cold water. Statistical tools were used to carry out the experimentations and its analysis. The result confirms, intercooling system minimizes the cutting forces and tool wear at considerable rates compared to non-intercooling system. Â© 2025 by authors.
Development of thermal model to analyze thermal flux distribution in thermally enhanced machining of high chrome white cast iron
(2018) Ravi, A.M.; Murigendrappa, S.M.
In recent times, thermally enhanced machining (TEM) slowly gearing up to cut hard metals like high chrome white cast iron (HCWCI) which were impossible in conventional procedures. Also setting up of suitable cutting parameters and positioning of the heat source against the work appears to be critical in order to enhance the machinability characteristics of the work material. In this research work, the Oxy - LPG flame was used as the heat source and HCWCI as the workpiece. ANSYS-CFD-Flow software was used to develop the transient thermal model to analyze the thermal flux distribution on the work surface during TEM of HCWCI using Cubic boron nitride (CBN) tools. Non-contact type Infrared thermo sensor was used to measure the surface temperature continuously at different positions, and is validated with the thermal model results. The result confirms thermal model is a better predictive tool for thermal flux distribution analysis in TEM process. � 2018 Author(s).
Development of thermal model to analyze thermal flux distribution in thermally enhanced machining of high chrome white cast iron
(American Institute of Physics Inc. subs@aip.org, 2018) Ravi, A.M.; Murigendrappa, S.M.
In recent times, thermally enhanced machining (TEM) slowly gearing up to cut hard metals like high chrome white cast iron (HCWCI) which were impossible in conventional procedures. Also setting up of suitable cutting parameters and positioning of the heat source against the work appears to be critical in order to enhance the machinability characteristics of the work material. In this research work, the Oxy - LPG flame was used as the heat source and HCWCI as the workpiece. ANSYS-CFD-Flow software was used to develop the transient thermal model to analyze the thermal flux distribution on the work surface during TEM of HCWCI using Cubic boron nitride (CBN) tools. Non-contact type Infrared thermo sensor was used to measure the surface temperature continuously at different positions, and is validated with the thermal model results. The result confirms thermal model is a better predictive tool for thermal flux distribution analysis in TEM process. Â© 2018 Author(s).
Experimental and Analytical Based Investigations on Machinability of High-Chrome White Cast Iron Using CBN Tools
(Springer, 2015) Ravi, A.M.; Murigendrappa, S.M.; Mukunda, P.G.
High-chrome white cast iron (HCWCI) is one of the hardest metals used in the process and mining industries faces tough challenge in metal cutting. Focusing on this issue, influence of cutting parameters (e.g., cutting speed, depth of cut, feed rate) on machinability characteristics (e.g., cutting forces, surface roughness, material removal rate, machining power) of HCWCI has been investigated by experimentally and analytically using cubic boron nitride (CBN) cutting tools. Experimentation is carried out in conjunction with the Taguchi techniques and the influence of each cutting parameter of the process has been analyzed by analytical tools; analysis of variance, regression technique and artificial neural networks (ANNs). The study reveals depth of cut has the highest contribution on the cutting forces, and cutting speed on surface roughness and machining power. The confirmation test identifies both regression and ANN techniques are the most effective tools to evaluate machinability characteristics of HCWCI. Further, the CBN cutting tool exhibits excellent performance in machining of HCWCI. © 2014, The Indian Institute of Metals - IIM.
Experimental investigation on thermally enhanced machining of high-chrome white cast iron and to study its machinability characteristics using Taguchi method and artificial neural network
(Springer-Verlag London Ltd, 2014) Ravi, A.M.; Murigendrappa, S.M.; Mukunda, P.G.
Machining of hard-to-wear materials such as high-chrome white cast iron (HCWCI) and high-manganese steels is an uphill task when conventional route followed. Alternatively, thermally enhanced machining (TEM) can be used to minimize the tooling cost very effectively. This paper presents the detailed study of TEM of HCWCI in which the effect of cutting parameters and surface temperature of the stock material on machinability characteristics (cutting forces and surface roughness) are analyzed using ANOVA and artificial neural network (ANN). The experimental work was conducted to follow Taguchi techniques. HCWCI is finding newer applications in mining; mineral processing industries were the workpiece in the machining studies using cobalt-based cubic boron nitride insert tool. Localized heat was added at the tool-work interface which softens the metal and eases the machining operation. The influences of the control factors on the process responses have been analyzed using analysis of variance (ANOVA), and the results are correlated using ANN. Linear regression was used to establish the relation between the control parameters and the process responses. The results show that TEM causes easy shearing of the material, leading to the reduction in cutting forces with expected improvement in tool life and surprisingly good surface finish. The confirmation tests suggest both second-order regression and ANN which are better predictive models for quantitative prediction of TEM of HCWCI, and ANN is more accurate of the two. Also, it was proved that oxy-LPG flame heating is an economical option compared to laser-heated machining in hard turning process. © 2014 Springer-Verlag London.
Experimental study on internal cooling system in hard turning of HCWCI using CBN tools
(2018) Ravi, A.M.; Murigendrappa, S.M.
In recent times, hard turning became most emerging technique in manufacturing processes, especially to cut high hard materials like high chrome white cast iron (HCWCI). Use of Cubic boron nitride (CBN), pCBN and Carbide tools are most appropriate to shear the metals but are uneconomical. Since hard turning carried out in dry condition, lowering the tool wear by minimizing tool temperature is the only solution. Study reveals, no effective cooling systems are available so for in order to enhance the tool life of the cutting tools and to improve machinability characteristics. The detrimental effect of cutting parameters on cutting temperature is generally controlled by proper selections. The objective of this paper is to develop a new cooling system to control tool tip temperature, thereby minimizing the cutting forces and the tool wear rates. The materials chosen for this work was HCWCI and cutting tools are CBN inserts. Intricate cavities were made on the periphery of the tool holder for easy flow of cold water. Taguchi techniques were adopted to carry out the experimentations. The experimental results confirm considerable reduction in the cutting forces and tool wear rates. � 2018 Author(s).
Experimental study on internal cooling system in hard turning of HCWCI using CBN tools
(American Institute of Physics Inc. subs@aip.org, 2018) Ravi, A.M.; Murigendrappa, S.M.
In recent times, hard turning became most emerging technique in manufacturing processes, especially to cut high hard materials like high chrome white cast iron (HCWCI). Use of Cubic boron nitride (CBN), pCBN and Carbide tools are most appropriate to shear the metals but are uneconomical. Since hard turning carried out in dry condition, lowering the tool wear by minimizing tool temperature is the only solution. Study reveals, no effective cooling systems are available so for in order to enhance the tool life of the cutting tools and to improve machinability characteristics. The detrimental effect of cutting parameters on cutting temperature is generally controlled by proper selections. The objective of this paper is to develop a new cooling system to control tool tip temperature, thereby minimizing the cutting forces and the tool wear rates. The materials chosen for this work was HCWCI and cutting tools are CBN inserts. Intricate cavities were made on the periphery of the tool holder for easy flow of cold water. Taguchi techniques were adopted to carry out the experimentations. The experimental results confirm considerable reduction in the cutting forces and tool wear rates. Â© 2018 Author(s).
Machinability investigations on high chrome white cast iron using multi coated hard carbide tools
(Springer India sanjiv.goswami@springer.co.in, 2014) Ravi, A.M.; Murigendrappa, S.M.; Mukunda, P.G.
This study investigated the performance of multilayer hard coated carbide tool and multi-response optimization of the turning process for an optimal parametric combination to yield the minimum cutting forces and machining power with a maximum material removal rate (MRR) using Taguchi and artificial neural network (ANN) methods. In recent times, high chrome white cast iron finds increasing applications in aerospace, mining, mineral process industries. Its machinability using carbide insert (TiC/TiCN/Al2O3) cutting tool has been studied. The influences of cutting parameters on the cutting forces, MRR and machining power of the process have been analyzed using analysis of variance and the results are correlated using ANN. Linear regression method was used to establish the relation between the cutting parameters and the process responses. The confirmation test reveals that, the accuracy of prediction of ANN is better than that of the regression analysis. In view of the good performance of the carbide tools (at optimum conditions), it can replace the cosly CBN, with improved economic benefits. © 2014 Indian Institute of Metals.
Wear studies in hard turning of high-chrome white cast iron using ANOVA and RSM techniques
(American Institute of Physics Inc. subs@aip.org, 2020) Ravi, A.M.; Murigendrappa, S.M.
In these days, tool wear is a major concern in hard turning process. Though the hybrid machining and thermally enhanced machining methods relieved the burden of the Industry to some extent, tool wear studies are more vital in order to improve the productivity. This research work mainly focuses on such studies wherein the influence of cutting parameters and tool temperature on tool wear are investigated both experimental and analytical procedures. The work material selected for the process was high-chrome white cast iron (HCWCI) and cutting tool as multi-layer hard coated carbide inserts. The experimental trials were carried out in accordance with the Taguchi's techniques. Second order regression was established to build the linear relationship among the process parameters and its responses. The research study reveals that flank and crater wear are the dominant wear patterns appeared in the process. The influencing parameters and their interactive effects on tool wear are also presented in graphical form which may useful while choosing the process parameters for better tool life. Â© 2020 Author(s).