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- High entropy alloy (3)
- Selective laser melting (3)
- Additive manufacturing (2)
- Bioprinting (2)
- Additive Manufacturing (1)
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- Air quality (1)
- Biofiltration (1)
- Bonding (1)
- CLT (1)
- CNC lathe machine (1)
- Carbon fiber reinforced polymer (1)
- Co-axial extrusion printing (1)
- Coaxial (1)
- Cold Spray (1)
- Collagen I (1)
- Cork (1)
- Cross (1)
- De Laval Nozzle (1)
- Design of Experiment (1)
- Diffusion (1)
- Dwell time (1)
- Emissions (1)
- High hardness steel (1)
- Hydrogels (1)
- Hydrogen embrittlement (1)
- Industrial pollutants (1)
- Injection molding (1)
- Lamina (1)
- Laminated (1)
- Laser-Induced Forward Transfer(LIFT) (1)
Articles 1 - 13 of 13
Full-Text Articles in Manufacturing
Study Of Alloy And Process Modifications To Design Hydrogen Resilient High Hardness Steels, William R. Williams
Study Of Alloy And Process Modifications To Design Hydrogen Resilient High Hardness Steels, William R. Williams
Theses and Dissertations
High hardness steels (HHS) are vulnerable to hydrogen embrittlement, which can lead to rapid degradation of mechanical properties. Improved resistance to hydrogen embrittlement would be beneficial to many industries including construction, automotive, and military. A comparison study was performed to assess the hydrogen susceptibility of select commercially available and in-house designed HHS alloys. Slow strain rate tensile tests, performed with specimens charged with various levels of hydrogen, provided a macroscopic view of the onset of hydrogen embrittlement. Hydrogen permeation and thermal desorption spectroscopy tests determined the uptake and diffusivity of hydrogen through the material. The evaluation of hydrogen susceptibility for …
Effects Of Bonding Pressure And Lamina Thickness On Mechanical Properties Of Clt Composed Of Southern Yellow Pine, Cody S. Bates
Effects Of Bonding Pressure And Lamina Thickness On Mechanical Properties Of Clt Composed Of Southern Yellow Pine, Cody S. Bates
Theses and Dissertations
This study produced cross-laminated timber panels at a range of four lamina thickness (5/8, 1, 1 1/8, and 1 1/4 inch) and three bonding pressures (50, 125, 200 psi), producing a total of 12 panels for mechanical testing. The goal of this study is to observe how the thickness and pressure trends affect the mechanical properties of CLT. Tests include flatwise bending, flatwise shear, internal-bond, and delamination. Results showed that bending MOE decreases as the panel thickness increases while bonding pressure had no significance. Bending MOR was less significant for the thickness and more significant for pressure compared to the …
Molecular Dynamics Study Of Atomic Diffusion In Cantor High Entropy Alloy In The Selective Laser Melting Process, Mathew Z. Farias
Molecular Dynamics Study Of Atomic Diffusion In Cantor High Entropy Alloy In The Selective Laser Melting Process, Mathew Z. Farias
Theses and Dissertations
High entropy alloys (HEAs) are compositionally complex alloys that are comprised of 5 or more principle elements at near equimolar concentrations. The Selective Laser Melting (SLM) method generally melts pure elemental powders or prefabricated alloy powders, this process allows for the production of heterogeneous structures that would be difficult to create through more conventional means. In-situ alloying in SLM, or Laser Additive Alloying (LAA), using pure elemental powders is a promising means of producing what would otherwise be costly and difficult to fabricate products with less defects using prefabricated powders, therefore this new approach could enable the ability to …
Selective Laser Melting Of Titanium Diboride: A Study Of The Energy Density Effects, Lazaro Lopez Mendez
Selective Laser Melting Of Titanium Diboride: A Study Of The Energy Density Effects, Lazaro Lopez Mendez
Theses and Dissertations
Natural titanium diboride (TiB2) has been reported the 5th hardest material on earth. Due to its superior properties, such as high density, high elastic modulus, and high compressive strength, TiB2 becomes one of the most suitable ceramic reinforcements for applications with severe friction and heavy loading conditions. This study is intended to produce TiB2 using 3D additive manufacture (AM) technology, and then to understand the tribological property of the AM fabricated TiB2 specimens. In this study, a laser additive alloying (LAA) process was developed based on a Renishaw AM laser system. One mm thick samples were prepared using the LAA …
Additive Manufacturing Of Cork, A Cold Spray Technology, Kimberly Kay Dickey
Additive Manufacturing Of Cork, A Cold Spray Technology, Kimberly Kay Dickey
Theses and Dissertations
Cold Spray Additive Manufacturing is a technology capable of mass manufacturing components with complicated geometry and coating substrates in hard-to-reach areas. In addition, cold spray also has the ability of conducting a green manufacturing process, with zero waste of renewable feed material, and zero gas and chemical emission. This paper investigates solely cold spray as an additive manufacturing technology with cork as the natural material. CFD results were used to predict the physical behavior of air and the cork particles. After unsuccessful coatings, final results showed that when moisture is added, cork is successfully cold sprayed, and agglomeration is experienced. …
Bioprinting A 3d Tubular Structure With Vascular Smooth Muscle Cells To Observe The Process Compatibility, Taieba Tuba Rahman
Bioprinting A 3d Tubular Structure With Vascular Smooth Muscle Cells To Observe The Process Compatibility, Taieba Tuba Rahman
Theses and Dissertations
Printability is the ability to print a reproducible structure using the bioprinting technique. Constructing the relationships between printability and printing parameters of the extrusion printing process is difficult because of the presence of too many independent and inter-correlated factors. For this reason, it is necessary to identify and limit the number of significantly influential factors. In addition, Scaffold based blood vessel fabrication is a key challenge in 3D Bioprinting. As vascular smooth muscle cell (VSMCs) is a major component of blood vessels, the investigation of the behavior and orientation of VSMCs after printing is required to better understand the 3D …
Machinability Of Carbon Fiber Reinforced Polymer (Cfrp) Composites: Modeling And Optimization Using Taguchi Analysis And Multi-Objective Genetic Algorithm, S M Abdur Rob
Theses and Dissertations
Carbon Fiber Reinforced Polymer (CFRP) composites have been widely used in aerospace, automotive, nuclear, and biomedical industries due to their high strength to weight ratio, corrosion resistant durability and excellent thermo-mechanical properties in non-oxidative atmospheres. Machining of CFRP composites has always been a challenge for the manufacturers. In this study, turning operation has been performed on CFRP composites to investigate the effects of cutting parameters namely cutting speed, feed rate and depth of cut on the output characteristics including cutting force, surface roughness and tool wear using Taguchi Analysis. Regression Analysis has been used to develop mathematical model for cutting …
Laser-Induced Forward Transfer (Lift) Based Bioprinting Of The Collagen I With Retina Photoreceptor Cells, Md Shakil Arman
Laser-Induced Forward Transfer (Lift) Based Bioprinting Of The Collagen I With Retina Photoreceptor Cells, Md Shakil Arman
Theses and Dissertations
This thesis focuses on the 3D bioprinting of retina cone cells using the laser-induced forward transfer (LIFT) technique. Bioprinting has a great potential to mimic and regenerate the human organoid system, and the LIFT technique has emerged as an efficient method for high resolution micropatterning and microfabrication of biomaterials and cells due to its capability of creating precise, controlled microdroplets. In this research, the parameters for an effective femtosecond laser-based LIFT process for 3D bioprinting of collagen biomaterial were studied. Different concentrations of collagen I solutions were tested to find out the right concentration that can be transferred through the …
Investigation Of Different Hatch Strategies On High Entropy Alloy Fabrication By Selective Laser Melting, Joni Chandra Dhar
Investigation Of Different Hatch Strategies On High Entropy Alloy Fabrication By Selective Laser Melting, Joni Chandra Dhar
Theses and Dissertations
This study investigated the synthesis of CuCrFeNiTiAl high entropy alloy (HEA) from pure elements using selective laser melting (SLM). The objectives are to validate the feasibility of the HEA fabrication from elemental powder materials, and to examine the effect of various hatch strategies and energy densities on the microstructures and other materials properties. 3D samples of CuCrFeNiTiAl alloy were fabricated under different energy densities and with different scan vector lengths. The as-built samples were characterized by X-ray diffraction (XRD), and the microstructures were observed using scanning electron microscopy (SEM). The XRD results showed that face centered cubic, and body centered …
Development Of Injection Molding Pressure Monitoring System Using Piezoelectric Sensor, Mostafa Meraj Pasha
Development Of Injection Molding Pressure Monitoring System Using Piezoelectric Sensor, Mostafa Meraj Pasha
Theses and Dissertations
Injection molding is one of the most popular techniques for global plastic production. With this automation technique, the plastic product can be manufactured at a low cost with a complex geometrical shape. A manufacturing process with the high productivity of an injection molding machine depends on molding pressure and temperature inside the mold cavity. In this research, an experimental work is performed to determine a process monitoring system using asynchronous data acquisition, through the incorporation of wired piezo-ceramic sensor to acquire pressure of injection molding system. This piezoelectric sensor is designed in such a way that, a Bluetooth device can …
Investigation Of Cell Behavior In 3d Printed Lumen Structures For Capillary Regeneration, Victoria Jade Perez
Investigation Of Cell Behavior In 3d Printed Lumen Structures For Capillary Regeneration, Victoria Jade Perez
Theses and Dissertations
This thesis work successfully generated a coaxial printing setup and process to generate 3D printed tubules. A dual syringe pump mechanism was developed to print tubular structures to investigate cell behavior with a goal to generate future capillary beds. The mechanism involves the use of collagen–alginate tubules and the use of EDTA to increase the porosity of the tubule structures to study their interaction with media and incubation techniques as well as behavior and morphology. Tubules of 1.7% sodium alginate and 0.4% collagen I reacting with 3.2% CaCl2 solution proved to be more stable in both the printing process and …
In-Situ Alloying Of Cucrfenitial High Entropy Alloy Using Spark Plasma Sintering, Yash P. Patil
In-Situ Alloying Of Cucrfenitial High Entropy Alloy Using Spark Plasma Sintering, Yash P. Patil
Theses and Dissertations
Primary objective of this research was to study the correlation between energy parameters (temperature, time and pressure) of spark plasma sintering (SPS) and design/structural properties (uniform distribution of elements, sever lattice distortion, density), indirectly proving consolidation of a stable High-entropy alloy (HEA) that consists of minimum of five elements. Therefore, powders of five principal elements (CuCrFeNiTi) and one minor element (Al) in near equimolar ratios were used for HEA consolidation using SPS but without mechanical alloying. Overall results demonstrated that the HEA was not generated using heterogenous solution of CuCrFeNiTiAl using SPS. This suggests that the mechanical alloying of CuCrFeNiTiAl …
Assessing The Feasibility Of A Biofilter In Medium-To-High Scale Industries, Javier A. Garcia
Assessing The Feasibility Of A Biofilter In Medium-To-High Scale Industries, Javier A. Garcia
Theses and Dissertations
The removal of volatile organic compounds, VOCs, from contaminated sources of air stream has become a major air pollution risk. Excessive amounts discharged to the atmosphere are highly risky to human health and to the environmental system. Demand for sustainable VOC control technologies has become crucial for the reduction of emissions. Biological treatments of waste gas streams, such as biofiltration, have proven to be cost effective and environmentally friendly compared to conventional pollution control technologies. The goal of this research is to simulate data for a given biofilter model, and to evaluate if it is economically and environmentally feasible to …