Directed Light Fabrication of Rhenium Components

Directed Light Fabrication of Rhenium Components

Author:

Publisher:

Published: 1997

Total Pages: 9

ISBN-13:

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Directed Light Fabrication (DLF) is a direct metal deposition process that fuses powder, delivered by gas into the focal zone of a high powered laser beam to form fully dense near-net shaped components. This is accomplished in one step without the use of molds, dies, forming, pressing, sintering or forging equipment. DLF is performed in a high purity inert environment free from the contaminants associated with conventional processing such as oxide and carbon pickup, lubricants, binding agents, cooling or cleaning agents. Applications using rhenium have historically been limited in part by its workability and cost. This study demonstrates the ability to fuse rhenium metal powder, using a DLF machine, into free standing rods and describes the associated parameter study. Microstructural comparisons between DLF deposited rhenium and commercial rhenium sheet product is performed. This research combined with existing DLF technology demonstrates the feasibility of forming complex rhenium, metal shapes directly from powder.


Rapid Fabrication of Materials Using Directed Light Fabrication

Rapid Fabrication of Materials Using Directed Light Fabrication

Author:

Publisher:

Published: 1997

Total Pages: 9

ISBN-13:

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Directed light fabrication (DLF) is a rapid fabrication process that fuses gas delivered metal powders within a focal zone of a laser beam to produce fully dense, near-net shape, 3-dimensional metal components from a computer generated solid model. Computer controls dictate the metal deposition pathways, and no preforms or molds are required to generate complex sample geometries. The focal zone of the laser beam is programmed to move along or across a part cross-section, and coupled with a multi-axis sample stage, produces the desired part. By maintaining a constant molten puddle within the focal zone, a continuous liquid/solid interface is possible while achieving constant cooling rates that can be varied between 10 to 104 K s−1 and solidification growth rates (that scale with the beam velocity) ranging up to 102 m s−1. The DLF technique offers unique advantages over conventional thermomechanical processes in that many labor and equipment intensive steps can be avoided. Moreover, owing to the flexibility in power distributions of lasers, a variety of materials can be processed, ranging from aluminum alloys to rhenium, and including intermetallics such as Mo5Si3. As a result, the rapid fabrication of conventional and advanced materials are possible.


Directed Light Fabrication of Refractory Metals

Directed Light Fabrication of Refractory Metals

Author:

Publisher:

Published: 1997

Total Pages: 9

ISBN-13:

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Directed Light Fabrication (DLF) is a metal, rapid fabrication process that fuses metal powders to full density into a solid replica of a computer modeled component. It has been shown feasible for forming nearly any metal and also intermetallics to near net shape with a single process. DLF of refractory pure metals is feasible, bypassing the extensive series of conventional processing steps used for processing these high melting point materials. Tungsten, tantalum, and rhenium were processed and show a continuous resolidified microstructure. Porosity was a problem for the tantalum and rhenium powders produced by chemical reduction processes but not for the tungsten powder spherodized in a plasma arc. Chemical analysis of powder compared to the DLF deposit showed reductions in carbon, oxygen and hydrogen, indicating that process parameters may also be optimized for evolution of residual gases in the deposits.


Near Net Shape Processing for Solar Thermal Propulsion Hardware Using Directed Light Fabrication

Near Net Shape Processing for Solar Thermal Propulsion Hardware Using Directed Light Fabrication

Author:

Publisher:

Published: 1998

Total Pages: 5

ISBN-13:

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Directed light fabrication (DLF) is a direct metal deposition process that fuses gas delivered powder, in the focal zone of a high powered laser beam to form fully fused near net shaped components. The near net shape processing of rhenium, tungsten, iridium and other high temperature materials may offer significant cost savings compared with conventional processing. This paper describes a 3D parametric solid model, integrated with a manufacturing model, and creating a control field which runs on the DLF machine directly depositing a fully dense, solid metal, near net shaped, nozzle component. Examples of DLF deposited rhenium, iridium and tantalum, from previous work, show a continuously solidified microstructure in rod and tube shapes. Entrapped porosity indicates the required direction for continued process development. These combined results demonstrate the potential for a new method to fabricate complex near net shaped components using materials of interest to the space and aerospace industries.


Encyclopedia and Handbook of Materials, Parts and Finishes

Encyclopedia and Handbook of Materials, Parts and Finishes

Author: Mel Schwartz

Publisher: CRC Press

Published: 2016-07-06

Total Pages: 2660

ISBN-13: 1138032069

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A great deal of progress has been made in the development of materials, their application to structures, and their adaptation to a variety of systems and integrated across a wide range of industrial applications. This encyclopedia serves the rapidly expanding demand for information on technological developments. In addition to providing information


New Materials, Processes, and Methods Technology

New Materials, Processes, and Methods Technology

Author: Mel Schwartz

Publisher: CRC Press

Published: 2005-11-04

Total Pages: 711

ISBN-13: 1420039342

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Materials selection is a crucial factor in determining the cost, quality, and corrosion protection for every engineering project. The variety of increasingly durable materials and their combinations, coupled with the rise of new and more critical service requirements and the demand for lower costs, have expanded upon trial-and-error criteria into m


Solar Engineering

Solar Engineering

Author: American Society of Mechanical Engineers. Solar Energy Division. Conference

Publisher:

Published: 1998

Total Pages: 524

ISBN-13:

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Processing and Fabrication of Advanced Materials X

Processing and Fabrication of Advanced Materials X

Author: T. S. Srivatsan

Publisher: ASM International(OH)

Published: 2002

Total Pages: 630

ISBN-13:

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Forty-one papers from the November 2001 symposium present research findings related to the processing, fabrication, and evaluation of advanced materials for manufacturing applications. The main subjects are structural and functional advanced materials, hydrogen storage materials, intermetallics, cer


Rapid Prototyping of Materials

Rapid Prototyping of Materials

Author: Fernand D. S. Marquis

Publisher: Minerals, Metals, & Materials Society

Published: 2002

Total Pages: 244

ISBN-13:

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Explores the state-of-the-art rapid prototyping manufacturing method and introduces the newest resulting materials. Rapid prototyping, also called solid free form fabrication, has grown into a mature manufacturing method used in a variety of fields. It is used in numerous materials systems that often cannot be processed by any other means. Furthermore, rapid prototyping has become a method by which new materials and composites can be formed. Recent examples involve the combining of preprocess processing with metal and alloy infiltration to form composite structure. This volume will also cover successful industrial and commercial uses of rapid prototyping and solid free form fabrication.