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Rasheedat M. Mahamood - One of the best experts on this subject based on the ideXlab platform.
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Laser Metal Deposition of Titanium Alloy (Ti6Al4V): A Review
2019 International Conference on Engineering Science and Industrial Applications (ICESI), 2019Co-Authors: Esther Titilayo Akinlabi, Yasuhiro Okamoto, Martin Ruthandi Maina, Stephen A. Akinlabi, Sisa Pityana, Monnamme Tlotleng, Ganiyat A. Soliu, Rasheedat M. MahamoodAbstract:Laser Metal Deposition (LMD) is an additive manufacturing (AM) technologies in that belongs to the class of direct energy Deposition which is suitable for manufacturing of alloys and composites materials. LMD is an efficient AM technique which is capable of producing end-use products starting from depositing the powder/wire material layer-by-layer. During LMD process, a laser beam is used as a heat source to generate a melt-pool on the substrate and melts the powder that is deposited through a co-axial nozzle and supported with a shielding gas that helps to prevent oxidation. LMD is capable of producing complex shaped and functionally graded parts which are useful in many industrial applications. This AM technology can also be used in repairing worn out parts that cannot be repaired by other manufacturing technology. In this paper, a review of laser Metal Deposition of titanium alloy is presented. This provides an overview of LMD of titanium alloys grade 5 (Ti6Al4V) and focuses on the effects of processing parameters on the overall evolving properties.
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Laser Metal Deposition of Metals and Alloys
Engineering Materials and Processes, 2017Co-Authors: Rasheedat M. MahamoodAbstract:Laser Metal Deposition process has evolved over the past two decades and it has provided the needed solution into a number of engineering problems. The capability of this additive manufacturing technology to produce end used parts directly from Metals and alloys is one of the attractive features of this manufacturing process. Laser Metal Deposition process can be used to create parts without the need for expensive and time wasting tooling. This technology helped to build near net shape components simply by adding materials layer after layer using the three dimensional (3D) model data of the part to be built. Laser Metal Deposition process is a true green manufacturing process that is capable of reducing material and energy wastages, help to reduce component lead time, and can also help to reduce carbon footprint through product remanufacturing capability. Any complex part that is difficult or prohibitive to be fabricated using the conventional manufacturing processes can readily be made using the laser Metal Deposition process. In this chapter, the use of laser Metal Deposition process for the processing of Metallic materials and alloys are discussed. The current research activities and the future research direction are also presented.
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Processing Parameters in Laser Metal Deposition Process
Engineering Materials and Processes, 2017Co-Authors: Rasheedat M. MahamoodAbstract:Laser Metal Deposition process is an important additive manufacturing process that is used to not only fabricate new three dimensional parts but can also be used to repair high valued parts. Laser Metal Deposition process has also position itself for product remanufacturing because of its capability to add a new part to an old part and with high Metallurgical integrity. Processing parameters play an important role in the evolving physical, Metallurgical and mechanical properties of the parts produced. The key processing parameters that influence the material properties in laser Metal Deposition process include: laser power, scanning velocity, powder flow rate, and gas flow rate. Laser Metal Deposition process is a highly non-linear process. A slight change in the processing parameters can result in a big change in the material properties. There is also a very strong interaction among these processing parameters. These processing parameters are analyzed in this chapter. There influences on the properties of the produced parts are explained. Some of the relevant literatures in this field are also presented.
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Introduction to Laser Metal Deposition Process
Engineering Materials and Processes, 2017Co-Authors: Rasheedat M. MahamoodAbstract:Additive manufacturing process is an advanced manufacturing process that fabricates components through the addition of materials as against the labour and energy intensive manufacturing processes which are based on material removal, or on application of heat and pressure. Laser Metal Deposition process belongs to a class of additive manufacturing process that can be used to fabricate three dimensional (3D) computer aided design model of the part by adding materials in a layer wise manner. Apart from the fabrication of 3D objects, laser Metal Deposition process can also be used to repair broken down parts and for the fabrication of parts that are made of composite and functionally graded materials. This important additive manufacturing technology is comprehensively dealt with in this book. This chapter briefly introduced the additive manufacturing (AM) process, the various classes of the AM technologies, laser Metal Deposition process, and the advantages as well as the limitation of these technologies.
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Future Research Need and in Laser Metal Deposition Process and Summary
Engineering Materials and Processes, 2017Co-Authors: Rasheedat M. MahamoodAbstract:This book presents the laser Metal Deposition process, and advanced manufacturing process that belongs to a class of additive manufacturing technologies for the production of Metals alloys and composite materials. The additive manufacturing technology was introduced and the brief background of the laser Metal Deposition process was also reviewed. The important energy source used in the laser Metal Deposition process is laser and it offers a number of capabilities that makes this manufacturing process to leave up what is expected. The laser was also reviewed in Chap. 2 of the book to bring to understanding of the reader and to know how important laser is in the laser Metal Deposition process. The processing parameters are of great importance in the laser Metal Deposition process and are also analyzed in this book. Areas of applications, case study and research advancement in laser Metal Deposition process are also presented. This chapter presents the future research direction in the field of laser Metal Deposition process and the chapter ends with the summary of the book.
Yukio H. Ogata - One of the best experts on this subject based on the ideXlab platform.
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Electrochemical Metal Deposition on silicon
Current Opinion in Solid State & Materials Science, 2006Co-Authors: Yukio H. Ogata, Katsutoshi Kobayashi, Munekazu MotoyamaAbstract:Electrochemical Metal Deposition is utilized to fabricate micro- and nano-structures. A variety of the structures have been achieved in Metal patterning and structuring and also in the structure formation of silicon itself. The controlling factors and conditions of the size, morphology and distribution have been investigated. The importance of Metal Deposition by displacement reaction should be recognized.
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Metal Deposition onto a Porous Silicon Layer by Immersion Plating from Aqueous and Nonaqueous Solutions
Journal of The Electrochemical Society, 2002Co-Authors: Farid A. Harraz, Takashi Tsuboi, Junji Sasano, Tetsuo Sakka, Yukio H. OgataAbstract:Immersion plating of Metals (Ag, Cu. Ni) onto a porous silicon (PS) layer from aqueous and nonaqueous solutions has been studied. The modified PS layers after the immersion plating were analyzed by X-ray diffraction and X-ray photoelectron spectroscopy. Fourier transform infrared spectroscopy and scanning electron microscopy were also performed to investigate the structural changes and microstructure of PS samples after the plating process. In booth solutions, the Deposition of Metal oxidizes PS simultaneously to SiO 2 . The different Deposition behaviors are discussed in terms of different rest potentials of PS in these solutions and electrode potential of each Metal. Immersion plating in nonaqueous organic solutions shows that a trace of residual water affects the Metal Deposition. Based on the results obtained, the mechanism of Metal Deposition is proposed. The Metal Deposition proceeds by nucleation and growth via the local cell mechanism. It is also found that Metal Deposition proceeds very differently on Si wafer and PS surfaces. The different Deposition behaviors on both surfaces are discussed.
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Metal Deposition into a porous silicon layer by immersion plating: Influence of halogen ions
Journal of Applied Physics, 1998Co-Authors: Takashi Tsuboi, Tetsuo Sakka, Yukio H. OgataAbstract:Metal Deposition into a porous silicon (PS) layer by immersion plating has been studied. Ag and Cu were found to deposit on PS, while Ni was found not to deposit. The dependence of the amount of Cu Deposition on Cu2+ concentration, halogen ion concentration, and immersion time was investigated using chelatometric titration. Copper Deposition from halide solutions exhibited an unusual behavior; the amount increased with increasing concentration, then decreased, and no copper deposited at high concentration. This is because adsorption of chloride and bromide ions inhibits the copper Deposition process. We have also discussed the Metal Deposition mechanism on the basis of x-ray diffraction, Fourier transform infrared spectroscopy, and x-ray photoelectron spectroscopy measurements. They revealed that Metal Deposition occurred simultaneously with the oxidation of silicon to SiO2. Copper crystals 30–80 nm in diameter deposited on the oxidized PS surface rather than on the unoxidized PS surface.
Jyoti Mazumder - One of the best experts on this subject based on the ideXlab platform.
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Robust sensing and control of direct Metal Deposition
Pacific International Conference on Applications of Lasers and Optics, 2008Co-Authors: Lijun Song, Jyoti MazumderAbstract:Direct Metal Deposition is one of the rapid manufacturing technologies to fabricate geometrically complicated, dense, near-net-shape components. Deposition process involves a large number of parameters, among which the laser power is considered as the primary variable. In order to develop a control system for the process, molten pool temperature during Deposition was monitored by a two-color pyrometer. Laser power and molten pool temperature form a single-input single-output system, whose dynamics were identified using a linear state space model. A generalized predictive control system with input constraints was designed for controlling the direct Metal Deposition process. To demonstrate the use of the proposed sensor and control algorithm, closed-loop experiments were conducted to adjust the laser power in order to track molten pool temperatures to the reference values.Direct Metal Deposition is one of the rapid manufacturing technologies to fabricate geometrically complicated, dense, near-net-shape components. Deposition process involves a large number of parameters, among which the laser power is considered as the primary variable. In order to develop a control system for the process, molten pool temperature during Deposition was monitored by a two-color pyrometer. Laser power and molten pool temperature form a single-input single-output system, whose dynamics were identified using a linear state space model. A generalized predictive control system with input constraints was designed for controlling the direct Metal Deposition process. To demonstrate the use of the proposed sensor and control algorithm, closed-loop experiments were conducted to adjust the laser power in order to track molten pool temperatures to the reference values.
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Robust sensing and predictive control of direct Metal Deposition
International Congress on Applications of Lasers & Electro-Optics, 2008Co-Authors: Lijun Song, Jyoti MazumderAbstract:Direct Metal Deposition is one of the rapid manufacturing technologies to fabricate geometrically complicated, dense, near-net-shape components. Deposition process involves a large number of parameters, among which the laser power is considered as the primary variable. In order to develop a control system for the process, molten pool temperature during Deposition was monitored by a two-color pyrometer. Laser power and molten pool temperature form a single-input single-output system, whose dynamics were identified using a linear state space model. A generalized predictive control system with input constraints was designed for controlling the direct Metal Deposition process. To demonstrate the use of the proposed sensor and control algorithm, closed-loop experiments were conducted to adjust the laser power in order to track molten pool temperatures to the reference values.Direct Metal Deposition is one of the rapid manufacturing technologies to fabricate geometrically complicated, dense, near-net-shape components. Deposition process involves a large number of parameters, among which the laser power is considered as the primary variable. In order to develop a control system for the process, molten pool temperature during Deposition was monitored by a two-color pyrometer. Laser power and molten pool temperature form a single-input single-output system, whose dynamics were identified using a linear state space model. A generalized predictive control system with input constraints was designed for controlling the direct Metal Deposition process. To demonstrate the use of the proposed sensor and control algorithm, closed-loop experiments were conducted to adjust the laser power in order to track molten pool temperatures to the reference values.
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Predictive control for direct Metal Deposition
International Congress on Applications of Lasers & Electro-Optics, 2007Co-Authors: Lijun Song, Jyoti MazumderAbstract:Direct Metal Deposition plays an important role in rapid manufacturing industry to fabricate geometrically complicated, dense, near-net-shape components. A large number of parameters are involved in the Deposition process. Its present development stagnates in its control. A good understanding of the laser material processing and a well designed controlling system are essential for the system reliability. This paper addresses the development of a linear model based generalized predictive control system for direct Metal Deposition. The molten pool temperature during the direct Metal Deposition process was monitored by a two-colour pyrometer. A single-input single-output linear system that describes the dynamics between the molten pool temperature and the laser power was considered. The incremental generalized predictive control algorithm with Kalman filter estimation was used to control the molten pool temperature. The performance of the controller was compared with the on-off controller.Direct Metal Deposition plays an important role in rapid manufacturing industry to fabricate geometrically complicated, dense, near-net-shape components. A large number of parameters are involved in the Deposition process. Its present development stagnates in its control. A good understanding of the laser material processing and a well designed controlling system are essential for the system reliability. This paper addresses the development of a linear model based generalized predictive control system for direct Metal Deposition. The molten pool temperature during the direct Metal Deposition process was monitored by a two-colour pyrometer. A single-input single-output linear system that describes the dynamics between the molten pool temperature and the laser power was considered. The incremental generalized predictive control algorithm with Kalman filter estimation was used to control the molten pool temperature. The performance of the controller was compared with the on-off controller.
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Sensing and experimental based modeling of direct Metal Deposition
International Congress on Applications of Lasers & Electro-Optics, 2006Co-Authors: Lijun Song, Jyoti MazumderAbstract:This paper presents an experimental investigation on the process dynamics of direct Metal Deposition. An optical sensing system, including three couple charged device cameras and a two-color pyrometer, is used to monitor molten pool geometry and pool temperature during the Deposition process. Molten pool area size and height are obtained by image processing. Auto regressive exogenous models and state space models are implemented to identify the direct Metal Deposition process relating laser power to molten pool temperature, as well as traverse speed to molten pool temperature. The models are validated by experimental data.This paper presents an experimental investigation on the process dynamics of direct Metal Deposition. An optical sensing system, including three couple charged device cameras and a two-color pyrometer, is used to monitor molten pool geometry and pool temperature during the Deposition process. Molten pool area size and height are obtained by image processing. Auto regressive exogenous models and state space models are implemented to identify the direct Metal Deposition process relating laser power to molten pool temperature, as well as traverse speed to molten pool temperature. The models are validated by experimental data.
Esther Titilayo Akinlabi - One of the best experts on this subject based on the ideXlab platform.
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Laser Metal Deposition of Titanium Alloy (Ti6Al4V): A Review
2019 International Conference on Engineering Science and Industrial Applications (ICESI), 2019Co-Authors: Esther Titilayo Akinlabi, Yasuhiro Okamoto, Martin Ruthandi Maina, Stephen A. Akinlabi, Sisa Pityana, Monnamme Tlotleng, Ganiyat A. Soliu, Rasheedat M. MahamoodAbstract:Laser Metal Deposition (LMD) is an additive manufacturing (AM) technologies in that belongs to the class of direct energy Deposition which is suitable for manufacturing of alloys and composites materials. LMD is an efficient AM technique which is capable of producing end-use products starting from depositing the powder/wire material layer-by-layer. During LMD process, a laser beam is used as a heat source to generate a melt-pool on the substrate and melts the powder that is deposited through a co-axial nozzle and supported with a shielding gas that helps to prevent oxidation. LMD is capable of producing complex shaped and functionally graded parts which are useful in many industrial applications. This AM technology can also be used in repairing worn out parts that cannot be repaired by other manufacturing technology. In this paper, a review of laser Metal Deposition of titanium alloy is presented. This provides an overview of LMD of titanium alloys grade 5 (Ti6Al4V) and focuses on the effects of processing parameters on the overall evolving properties.
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laser Metal Deposition of functionally graded ti6al4v tic
Materials & Design, 2015Co-Authors: Rasheedat M. Mahamood, Esther Titilayo AkinlabiAbstract:Abstract Functionally graded materials (FGMs) are advanced materials with improved properties that enable them to withstand severe working environment which the traditional composite materials cannot withstand. FGM found their applications in several areas which include: military, medicine and aerospace. Various manufacturing processes are used to produce functionally graded materials that include: powder Metallurgy, physical vapour Deposition, chemical vapour Deposition process and laser Metal Deposition process. Laser Metal Deposition (LMD) process is an additive manufacturing process that can be used to produce functionally graded material directly from the three dimensional (3D) computer aided design (CAD) model of the part in one single process. LMD process is a fairly new manufacturing process and a highly non-linear process. The process parameters are of great importance in LMD process and they need to be optimized for the required application. In this study, functionally graded titanium alloy composite was produced using optimized process parameters for each material combination as obtained through a model that was developed in an initial study and the FGM was characterized through Metallurgical, mechanical and tribological studies. The results show that the produced FGM has improved properties when compared to those produced at constant processing parameters for all material combinations.
Guifang Sun - One of the best experts on this subject based on the ideXlab platform.
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microstructure evolution during laser aided direct Metal Deposition of alloy tool steel
Scripta Materialia, 2011Co-Authors: Guifang Sun, Sudip Bhattacharya, G P Dinda, A K Dasgupta, Jyotirmoy MazumderAbstract:Laser-aided direct Metal Deposition has been used to form an alloy tool steel coating. The microstructure of the deposited material was analyzed by means of scanning electron microscopy and transmission electron microscopy. The formation relationships among martensite, e-carbide, cementite and austenite in the coating are discussed. The effect of rapid solidification associated with direct Metal Deposition on lattice parameters is also reported.
