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- <p>Rapid prototyping<br />Solid freeform fabrication<br />Ceramics -- Extrusion</p> (1)
- <p>Zirconium compounds -- Extrusion<br />Rapid prototyping<br />Ceramic-matrix composites -- Mechanical properties<br />Ceramic-matrix composites -- Microstructure<br />Sintering</p> (1)
- Aircraft Landing Gear Applications (1)
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- LMD (1)
- Landing Gear (aircraft) (1)
- Laser-Cladding Process (1)
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- Stainless Steel (1)
- Stainless Steel 316L (1)
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Articles 1 - 8 of 8
Full-Text Articles in Manufacturing
Increase Of Heat Transfer To Reduce Build Time In Rapid Freeze Prototyping, Ming-Chuan Leu, Sriram Praneeth Isanaka, Von Richards
Increase Of Heat Transfer To Reduce Build Time In Rapid Freeze Prototyping, Ming-Chuan Leu, Sriram Praneeth Isanaka, Von Richards
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Reduction of part build time in the Rapid Freeze Prototyping (RFP) process, which fabricates a 3D ice part layer-by-layer by depositing and freezing water droplets, has been achieved by increase of heat transfer. Three mechanisms have been experimentally investigated: 1) cooling the substrate, 2) use of forced convection, and 3) use of a chilling plate. Cooling the substrate is effective for parts of small heights but becomes ineffective with increase in part height. Forced convection produced desirable reduction in part build time but with the undesirable formation of frost on the built ice part. The use of chilling plate to …
Development Of Extrusion-On-Demand For Ceramic Freeze-Form Extrusion Fabrication, Thomas Oakes, Parimal Kulkarni, Robert G. Landers, Ming-Chuan Leu
Development Of Extrusion-On-Demand For Ceramic Freeze-Form Extrusion Fabrication, Thomas Oakes, Parimal Kulkarni, Robert G. Landers, Ming-Chuan Leu
Mechanical and Aerospace Engineering Faculty Research & Creative Works
In the Freeze-form Extrusion Fabrication (FEF) process, extrusion-on-demand (EOD) refers to the ability to control the start and stop of paste extrusion on demand and is vital to the fabrication of parts with complex geometries. This paper describes the development of EOD for ceramic FEF through modeling and control of extrusion force, selection of appropriate process parameters, and a dwell technique for start and stop of extrusion. A general tracking controller with integral action is used to allow tracking of a variety of reference forces while accounting for the variability in the paste properties. Experiments are conducted to model the …
Evaluation Of Direct Diode Laser Deposited Stainless Steel 316l On 4340 Steel Substrate For Aircraft Landing Gear Application, Tian Fu, Todd E. Sparks, Frank W. Liou, Joseph William Newkirk, Zhiqiang Fan, Syamala Rani Pulugurtha, Jianzhong Ruan, Hsin-Nan Chou
Evaluation Of Direct Diode Laser Deposited Stainless Steel 316l On 4340 Steel Substrate For Aircraft Landing Gear Application, Tian Fu, Todd E. Sparks, Frank W. Liou, Joseph William Newkirk, Zhiqiang Fan, Syamala Rani Pulugurtha, Jianzhong Ruan, Hsin-Nan Chou
Mechanical and Aerospace Engineering Faculty Research & Creative Works
300M steel is used extensively for aircraft landing gears because of its high strength, ductility and toughness. However, like other high-strength steels, 300M steel is vulnerable to corrosion fatigue and stress corrosion cracking, which can lead to catastrophic consequences in the landing gear. Stainless steels offer a combination of corrosion, wear, and fatigue properties. But for an aircraft landing gear application a higher surface hardness is required. A laser cladding process with fast heating and cooling rates can improve the surface hardness. AISI 4340 steel is used as a lower cost alternative to 300M due to its similar composition. In …
Fuel Cell Development Using Additive Manufacturing Technologies -- A Review, Nikhil P. Kulkarni, Gargi Tandra, Frank W. Liou, Todd E. Sparks, Jianzhong Ruan
Fuel Cell Development Using Additive Manufacturing Technologies -- A Review, Nikhil P. Kulkarni, Gargi Tandra, Frank W. Liou, Todd E. Sparks, Jianzhong Ruan
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Fuel cells are being perceived as the future clean energy source by many developed countries in the world. The key today for clean power is the reliance of fuel cells not only to power automobiles but also for residential, small commercial, backup power etc. which calls for production on a large scale. Additive manufacturing is perceived as a way to develop cost effective fuel cells. It imparts flexibility to design different kinds of fuel cells along with reduction in material wastage. This paper deals with the review of additive manufacturing processes for research and development of fuel cell components, such …
Functionally Graded Materials By Laser Metal Deposition, Syamala Rani Pulugurtha, Joseph William Newkirk, Frank W. Liou, Hsin-Nan Chou
Functionally Graded Materials By Laser Metal Deposition, Syamala Rani Pulugurtha, Joseph William Newkirk, Frank W. Liou, Hsin-Nan Chou
Materials Science and Engineering Faculty Research & Creative Works
Fabrication of functionally graded materials (FGMs) by laser metal deposition (LMD) has the potential to offer solutions to key engineering problems over the traditional metal-working techniques. But the issues that need to be addressed while building FGMs are intermixing in the layers and cracking due to the residual stresses. This paper is to present the study of the effect of process parameters (laser power and travel speed) on the degree of dilution between the substrate (or, previous layer) and powder material for few metallurgical systems.
Development Of A Melt Pool Tracking Vision System For Laser Deposition, Todd E. Sparks, Lie Tang, Frank W. Liou
Development Of A Melt Pool Tracking Vision System For Laser Deposition, Todd E. Sparks, Lie Tang, Frank W. Liou
Mechanical and Aerospace Engineering Faculty Research & Creative Works
This paper chronicles the development of a vision system for tracking melt pool morphology in the laser metal deposition process. This development is to augment an existing temperature feedback control system. Monitoring both the temperature and shape of the melt pool is necessary because of the effects of local geometry on the cooling rate at the melt pool. Temperature feedback alone cannot accommodate this effect without complex process planning. The vision system's hardware, software, and integration into the laser deposition system's controller is detailed in this paper. Preliminary testing and the effects on depositionquality is also discussed.
Investigation Of Selective Laser Sintering Of Zirconium Diboride Parts, Shashwatashish Pattnaik
Investigation Of Selective Laser Sintering Of Zirconium Diboride Parts, Shashwatashish Pattnaik
Masters Theses
"This research investigates the fabrication of three-dimensional parts from ZrB₂, an ultra high temperature ceramic (UHTC), using the selective laser sintering (SLS) process. Based on an experimental investigation, optimum values for the SLS parameters (scan speed, laser power, energy density, scan spacing and layer thickness), used on a DTM Sinterstation 2000, were determined to build green ZrB₂ parts with high integrity and sharp geometrical features. This was done by melting the polymer binder used to bond the ceramic particles layer-by-layer according to the cross-section of a CAD model. The use of a sacrificial plate to eliminate cracks in the bottom …
Development Of Extrusion On Demand For Ceramic Freeze-Form Extrusion Fabrication Processes, Parimal Sanjay Kulkarni
Development Of Extrusion On Demand For Ceramic Freeze-Form Extrusion Fabrication Processes, Parimal Sanjay Kulkarni
Masters Theses
"Freeze-form Extrusion Fabrication (FEF) is a Solid Freeform Fabrication method. It involves the deposition of a ceramic paste in a layer by layer manner to construct a three dimensional structure. The ceramic paste used in this process consists of a high solids loading of ceramic powder mixed with water and a nominal amount of an aqueous organic binder. These characteristics make the process environmentally friendly. Also the absence of dies or molds in the process makes it suitable for fabrication of materials like ceramics. In the past, parts have been fabricated with continuous extrusion of a ceramic paste. In FEF, …