The Experts below are selected from a list of 15327 Experts worldwide ranked by ideXlab platform
Mark Easton - One of the best experts on this subject based on the ideXlab platform.
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Laser Additive Manufacturing - Powder Bed fusion processes
Laser Additive Manufacturing, 2017Co-Authors: S. Sun, Milan Brandt, Mark EastonAbstract:Abstract Additive manufacturing is a manufacturing process in which functional parts can be made by adding materials without using special tooling, jigs or fixtures. It provides tremendous advantages compared with traditional subtractive manufacturing processes, such as shorter lead times, less waste, the ability to make more complex parts and a cost independent of complexity. Powder Bed fusion processes in laser-based additive manufacturing have received significant attention in the research and development of advanced engineering materials because of their higher cooling rate and better surface finish compared with other additive manufacturing processes. This chapter summarizes the recent research in the laser-based Powder Bed fusion process. It covers the characteristics of the process and melt pool; microstructural features including texture, residual stress and defects; and characteristics of mechanical properties of metallic parts processed by the laser-based Powder Bed fusion process.
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Powder Bed fusion processes: An overview
Laser Additive Manufacturing: Materials Design Technologies and Applications, 2016Co-Authors: S. Sun, Milan Brandt, Mark EastonAbstract:Additive manufacturing is a manufacturing process in which functional parts can be made by adding materials without using special tooling, jigs or fixtures. It provides tremendous advantages compared with traditional subtractive manufacturing processes, such as shorter lead times, less waste, the ability to make more complex parts and a cost independent of complexity.Powder Bed fusion processes in laser-based additive manufacturing have received significant attention in the research and development of advanced engineering materials because of their higher cooling rate and better surface finish compared with other additive manufacturing processes. This chapter summarizes the recent research in the laser-based Powder Bed fusion process. It covers the characteristics of the process and melt pool; microstructural features including texture, residual stress and defects; and characteristics of mechanical properties of metallic parts processed by the laser-based Powder Bed fusion process.
Matteo Seita - One of the best experts on this subject based on the ideXlab platform.
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A high-resolution and large field-of-view scanner for in-line characterization of Powder Bed defects during additive manufacturing
Materials & Design, 2019Co-Authors: Le Tan Phuc, Matteo SeitaAbstract:Abstract Powder Bed defects are irregularities in the Powder layer, which alter the energy input during the Powder Bed fusion process. As a result, they are directly responsible for the formation of flaws in the consolidated material, which cause quality and property variability in additive manufactured parts. Because of their small size and ubiquity across the Powder Bed, Powder Bed defects are difficult to detect and correct. In this work, we propose a new method to assess Powder Bed defects across the entire Powder Bed at the remarkable spatial resolution of ~5 μm. Our method relies on the integration of a contact image sensor taken from a flatBed document scanner to the Powder re-coater module. Owing to the narrow depth-of-field of the sensor, we detect Powder Bed defects by identifying out-of-focus regions in the acquired scans using numerical image analysis techniques. Moreover, we show that we can assess the defects height (or depth) by quantifying the degree of “blurriness” in such regions. Our “Powder Bed scanner” is a rapid and cost-effective tool for in-line characterization of the Powder Bed quality. This technology may be instrumental to develop novel close loop strategies aimed at improving the consistency of additive manufactured parts.
Shawn P. Moylan - One of the best experts on this subject based on the ideXlab platform.
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Measurement of Powder Bed density in Powder Bed fusion additive manufacturing processes
Measurement Science and Technology, 2016Co-Authors: Gregor Jacob, Alkan Donmez, John A. Slotwinski, Shawn P. MoylanAbstract:Many factors influence the performance of additive manufacturing (AM) processes, resulting in a high degree of variation in process outcomes. Therefore, quantifying these factors and their correlations to process outcomes are important challenges to overcome to enable widespread adoption of emerging AM technologies. In the Powder Bed fusion AM process, the density of the Powder layers in the Powder Bed is a key influencing factor. This paper introduces a method to determine the Powder Bed density (PBD) during the Powder Bed fusion (PBF) process. A complete uncertainty analysis associated with the measurement method was also descriBed. The resulting expanded measurement uncertainty, U PBD ( k = 2), was determined as 0.004 g · cm −3 . It was shown that this expanded measurement uncertainty is about three orders of magnitude smaller than the typical Powder Bed density. This method enables establishing correlations between the changes in PBD and the direction of motion of the Powder recoating arm.
S. Sun - One of the best experts on this subject based on the ideXlab platform.
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Laser Additive Manufacturing - Powder Bed fusion processes
Laser Additive Manufacturing, 2017Co-Authors: S. Sun, Milan Brandt, Mark EastonAbstract:Abstract Additive manufacturing is a manufacturing process in which functional parts can be made by adding materials without using special tooling, jigs or fixtures. It provides tremendous advantages compared with traditional subtractive manufacturing processes, such as shorter lead times, less waste, the ability to make more complex parts and a cost independent of complexity. Powder Bed fusion processes in laser-based additive manufacturing have received significant attention in the research and development of advanced engineering materials because of their higher cooling rate and better surface finish compared with other additive manufacturing processes. This chapter summarizes the recent research in the laser-based Powder Bed fusion process. It covers the characteristics of the process and melt pool; microstructural features including texture, residual stress and defects; and characteristics of mechanical properties of metallic parts processed by the laser-based Powder Bed fusion process.
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Powder Bed fusion processes: An overview
Laser Additive Manufacturing: Materials Design Technologies and Applications, 2016Co-Authors: S. Sun, Milan Brandt, Mark EastonAbstract:Additive manufacturing is a manufacturing process in which functional parts can be made by adding materials without using special tooling, jigs or fixtures. It provides tremendous advantages compared with traditional subtractive manufacturing processes, such as shorter lead times, less waste, the ability to make more complex parts and a cost independent of complexity.Powder Bed fusion processes in laser-based additive manufacturing have received significant attention in the research and development of advanced engineering materials because of their higher cooling rate and better surface finish compared with other additive manufacturing processes. This chapter summarizes the recent research in the laser-based Powder Bed fusion process. It covers the characteristics of the process and melt pool; microstructural features including texture, residual stress and defects; and characteristics of mechanical properties of metallic parts processed by the laser-based Powder Bed fusion process.
Angela Davies - One of the best experts on this subject based on the ideXlab platform.
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In situ surface topography of laser Powder Bed fusion using fringe projection
Additive Manufacturing, 2016Co-Authors: Bin Zhang, John Ziegert, Faramarz Farahi, Angela DaviesAbstract:Being able to characterize the process signatures of Powder Bed based additive manufacturing process is key to improving the product quality. This paper demonstrates the implementation of a digital fringe projection technique to measure surface topography of the Powder Bed layers during the fabrication. We focus on developing the metrology tool and observing the types of information that can be extracted from such topographical data. The performance of the system is demonstrated with selected in situ measurements. Experimental results show this system is capable of measuring Powder Bed signatures including the Powder layer flatness, surface texture, the average height drop of the fused regions, characteristic length scales on the surface, and splatter drop location and dimension.
