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Showing 1 to 20 of 22 for “"freeform fabrication"”.
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Solid freeform fabrication using semi-solid processing
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1995.
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A surface texture modeling system for solid freeform fabrication
Solid Freeform Fabrication, SFF, is a set of manufacturing processes that fabricates parts as a bonded stack of individual layers. The Three Dimensional Printing process, 3DPTM process, is an SFF technology developed at MIT. It builds layers by ink jet printing binder onto the surface of a bed of …
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Carbide formation in a nickel-based superalloy during electron beam solid freeform fabrication
The Electron Beam Solid Freeform Fabrication process involves the use of an electron beam to make near-net-shape metal parts without the need for tooling. Material in wire form is fed into a melt pool maintained on the surface of the part by the electron beam and a positioning system causes the …
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Combined Compression and Shear Structural Evaluation of Stiffened Panels Fabricated Using Electron Beam Freeform Fabrication
… current aircraft structures. The Electron Beam Freeform Fabrication (EBF3) process can be used to manufacture unitized aircraft structures. The structural efficiency of blade stiffened panels made with EBF3 was compared to panels made by integrally machining from thick plate. The panels were …
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A pneumatic conveying powder delivery system for continuously heterogeneous material deposition in solid freeform fabrication
… continuously being made in the solid free form fabrication (SFF) industry in terms of processes and materials. Fully functional parts are being created directly with little, if any, finishing. Parts are being directly fabricated with engineering materials such as ceramics and metals. This thesis …
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Formulation of oral dosage forms by three dimensional printing
Pharmaceutical grade materials were used in the fabrication of fast-release and extended-release oral dosage forms. Tablets were processed by employing a method of solid freeform fabrication known as three dimensional printingTM (3DPTM). A microcrystalline cellulose powder was used in combination …
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Rapid tooling by integration of solid freedom fabrication and electrodepostion
Rapid tooling (RT) techniques based on solid freeform fabrication (SFF) are being studied worldwide to speed up the design-production cycle and thus keep manufacturers at a competitive edge. This dissertation presents a novel rapid tooling process that integrates SFF with electrodeposition to …
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Rapid Prototyping Job Scheduling Optimization
… rapid prototyping systems (i.e., solid freeform fabrication, layered manufacturing) rely on human intervention to load and unload build jobs. Hence, jobs are processed subject to both the machine's and the operator's schedules. In particular, first-in-first-out (FIFO) queuing of such …
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Transient liquid-phase infiltration of a powder-metal skeleton
… infiltration and full-density sintering. Fabrication of direct metal parts with complex geometry is possible using TLI in conjunction with Solid Freeform Fabrication (SFF) processes such as Three-Dimensional Printing, which produce net-shape skeletons of powdered metal directly from CAD …
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Vibration Analysis of a Composite Wing Box with Arbitrarily Shaped Spars and Ribs
… technologies, such as Electron Beam Freeform Fabrication and Friction Stir Welding, have allowed the manufacturing of arbitrarily shaped stiffeners. Curvilinear stiffeners provide flexibility in design as they can assume an infinite number of paths. Curvilinear spars and ribs can in …
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Strengthening porous metal skeletons by metal deposition from a nanoparticle dispersion
The accuracy of solid freeform fabrication processes such as three-dimensional printing (3DP) and selective laser sintering (SLS) must be improved for them to achieve wide application in direct production of metal parts. This work seeks to reduce sintering and deformation of porous metal skeletons …
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Fabrication of complex oral drug delivery forms by Three Dimensional Printing (tm)
Three Dimensional Printing 3DPTM is a novel solid freeform fabrication technology that has been applied to the fabrication of complex pharmaceutical drug devices. Limitations of the technology as relating to pharmaceuticals have been addressed and prototype dosage forms have been fabricated. The …
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Vector drop-on-demand production of tungsten carbide-cobalt tooling inserts by three dimensional printing
Three Dimensional Printing (3DP) is a solid freeform fabrication process used to generate solid parts directly from three-dimensional computer models. A part geometry is created by selectively depositing binder into sequentially spread layers of powder. In slurry-based 3DP, a suspension of powder …
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Direct laser sintering of stainless steel : thermal experiments and numerical modelling
SLS is a commercial solid freeform fabrication process. Layers of powder material are bonded by a laser beam to rapidly manufacture three dimensional freeform models. In this work, the direct SLS of room temperature single-phase steel powder beds is researched. Two approaches are adopted: - …
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Conformal cooling and rapid thermal cycling in injection molding with 3D printed tools
Solid Freeform Fabrication processes such as 30 Printing have demonstrated the potential to produce tools with complex internal geometry. This work explores the application of this capability to improved thermal management for injection molding tooling through: i)cooling lines which are conformal …
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Nanotube reinforced thermoplastic polymer matrix composites
… The two studies demonstrate the effect of solid freeform fabrication (SFF) and chemical functionalization on anisotropy and limited reactivity, respectively. Both studies showed mechanical property improvements. The alignment study demonstrates a maximum increase of 93% in tensile modulus with …
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Rehardenable materials system with diffusion barrier for three-dimensional printing
Three-Dimensional Printing (3DP) is a solid freeform fabrication process being developed for the direct manufacture of functional tooling and prototypes from a computer solid model. One of its many important applications is the fabrication of metal tooling for plastic injection molding. In order to …
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Fabrication of engineered ceramic components by the slurry-based three dimensional printing process
… ceramic components. The process is a solid freeform fabrication (SFF) technique that builds components directly from a computer CAD file on a layer-by-layer basis. Solid-liquid interactions play a primary role in the process physics of each stage of the process. The formation of the powder …
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Analysis of functionally graded material object representation methods
Solid Freeform Fabrication (SFF) processes have demonstrated the ability to produce parts with locally controlled composition. To exploit this potential, methods to represent and exchange parts with varying local composition need to be proposed and evaluated. In modeling such parts efficiently, any …
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The fabrication of high packing density ceramic powder beds for the three dimensional printing process
Three Dimensional Printing is a solid freeform fabrication process which can be used to create parts directly from CAD models. In the past, the 3DP process has been used to create structural ceramic parts using spray dried powders. Although fully dense parts have been made, it has been necessary to …
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