Free Form Fabrication of Metallic Components Using the Directed Light Fabrication Process
Free Form Fabrication of Metallic Components Using the Directed Light Fabrication Process

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Publisher:

Published: 1998

Total Pages: 9

ISBN-13:

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The Directed Light Fabrication (DLF) process uses a laser beam and metal powder, fed into the laser focal zone, to produce free standing metal components that are fully dense and have structural properties equivalent to conventional metal forming processes. The motion of the laser focal zone is precisely controlled by a motion path produced from a 3 dimensional solid model of a desired component. The motion path commands move the focal zone of the laser such that all solid areas of the part are deposited and the part can be built (deposited) in its entirety to near net shape, typically within " 0.13 mm. The process is applicable to any metal or intermetallic. Full density and mechanical properties equivalent to conventionally processed material are achieved.

Free-form Processing of Near-net Shapes Using Directed Light Fabrication
Free-form Processing of Near-net Shapes 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, three-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 with accurate and precise tolerances. The DLF technique offers unique advantages over conventional thermomechanical processes or thermal spray processes in that many labor and equipment intensive steps can be avoided to produce components with fully dense microstructures. Moreover, owing to the flexibility in power distributions of lasers, a variety of materials have been processed, ranging from aluminum alloys to tungsten, and including intermetallics such as Mo5Si3. Since DLF processing offers unique capabilities and advantages for the rapid fabrication of complex metal components, an examination of the microstructural development has been performed in order to define and optimize the processed materials. Solidification studies of DLF processing have demonstrated that a continuous liquid/solid interface is maintained while achieving high constant cooling rates that can be varied between 10 to 105 K s−1 and solidification growth rates ranging up to the 10−2 m s−1.

Properties of Near-net Shape Metallic Components Made by the Directed Light Fabrication Process
Properties of Near-net Shape Metallic Components Made by the Directed Light Fabrication Process

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Published: 1997

Total Pages: 10

ISBN-13:

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Directed Light Fabrication (DLF) is a process invented at Los Alamos National Laboratory that can be used to fuse any metal powder directly to a fully dense, near-net shape component with full structural integrity. A solid model design of a desired component is first developed on a computer work station. A motion path, produced from the solid model definition, is translated to actual machine commands through a post-processor, specific to the deposition equipment. The DLF process uses a multi-axis positioning system to move the laser focal zone over the part cross section defined by the part boundaries and desired layer thickness. Metal powders, delivered in an argon stream, enter the focal zone where they melt and continuously form a molten pool of material that moves with the laser focal spot. Position and movement of the spot is controlled through the post-processor. Successive cross-sectional layers are added by advancing the spot one layer thickness beyond the previous layer until the entire part is deposited. The system has 4 powder feeders attached for co-deposition of multiple materials to create alloys at the focal zone or form dissimilar metal joint combinations by changing powder composition from one material to another. Parts produced by the DLF process vary in complexity from simple bulk solid forms to detailed components fabricated from difficult to process metals and alloys. Parts have been deposited at rates up to 33 cm3/hr with 12 cm3/hr more typical. Feasibility of processing any metal ranging in melting point from aluminium to tungsten has been demonstrated. Mechanical properties for bulk DLF deposits of three alloy powders were measured for this study. Ti-6Al-4V and 316 stainless steel powders were fabricated into rectangular bar, and Inconel 690 powder was fabricated into a solid cylinder.

Directed Light Fabrication--a Laser Metal Deposition Process for Fabrication of Near-net Shape Components
Directed Light Fabrication--a Laser Metal Deposition Process for Fabrication of Near-net Shape Components

Author:

Publisher:

Published: 1997

Total Pages: 18

ISBN-13:

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This is the final report of a two-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Directed Light Fabrication (DLF) is a direct metal deposition process developed at LANL. A solid computer model is used to generate a tool path that moves a laser beam within the required part boundaries to deposit a planar metal layer (about .1 mm thick) which is successively stacked to build the entire part. Metal powder particles are introduced into the laser focal zone where they melt and then solidify to produce a fully dense deposited layer. In a single processing step, metal components are formed eliminating the series of processing steps required by conventional processing such as forging, stamping, casting, etc. The accomplishments of this project have been as follows; (1) advancement of the technology from 3 axes of motion to 5 axes of motion producing true three-dimensional components and assemblies; (2) development of a workable machine for accurate powder delivery, powder recycle, and gas recycle; and (3) demonstrated feasibility for processing almost any metal and intermetallic compound.

Solid Freeform Fabrication: A New Direction in Manufacturing
Solid Freeform Fabrication: A New Direction in Manufacturing

Author: J.J. Beaman

Publisher: Springer Science & Business Media

Published: 2013-11-27

Total Pages: 332

ISBN-13: 1461563275

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Solid Freeform Fabrication is a set of manufacturing processes that are capable of producing complex freeform solid objects directly from a computer model of an object without part-specific tooling or knowledge. In essence, these methods are miniature manufacturing plants which come complete with material handling, information processing and materials processing. As such, these methods require technical knowledge from many disciplines; therefore, researchers, engineers, and students in Mechanical, Chemical, Electrical, and Manufacturing Engineering and Materials and Computer Science will all find some interest in this subject. Particular subareas of concern include manufacturing methods, polymer chemistry, computational geometry, control, heat transfer, metallurgy, ceramics, optics, and fluid mechanics. History of technology specialists may also find Chapter 1 of interest. Although this book covers the spectrum of different processes, the emphasis is clearly on the area in which the authors have the most experience, thermal laser processing. In particular, the authors have all been developers and inventors of techniques for the Selective Laser Sintering process and laser gas phase techniques (Selective Area Laser Deposition). This is a research book on the subject of Solid Freeform Fabrication.

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
Directed Light Fabrication

Author:

Publisher:

Published: 1994

Total Pages: 11

ISBN-13:

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Directed Light Fabrication (DLF) is a rapid prototyping process being developed at Los Alamos National Laboratory to fabricate metal components. This is done by fusing gas delivered metal powder particles in the focal zone of a laser beam that is, programmed to move along or across the part cross section. Fully dense metal is built up a layer at a time to form the desired part represented by a 3 dimensional solid model from CAD software. Machine ''tool paths'' are created from the solid model that command the movement and processing parameters specific to the DLF process so that the part can be built one layer at a time. The result is a fully dense, near net shape metal part that solidifies under rapid solidification conditions.

Free Form Fabrication of Metallic Components Using Laser Engineered Net Shaping (LENS{trademark}).
Free Form Fabrication of Metallic Components Using Laser Engineered Net Shaping (LENS{trademark}).

Author:

Publisher:

Published: 1996

Total Pages: 7

ISBN-13:

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Solid free form fabrication is one of the fastest growing automated manufacturing technologies that has significantly impacted the length of time between initial concept and actual part fabrication. Starting with CAD renditions of new components, several techniques such as stereolithography and selective laser sintering are being used to fabricate highly accurate complex three-dimensional concept models using polymeric materials. Coupled with investment casting techniques, sacrificial polymeric objects are used to minimize costs and time to fabricate tooling used to make complex metal castings. This paper will describe recent developments in a new technology, known as LENS{sup {trademark}} (Laser Engineered Net Shaping), to fabricate metal components directly from CAD solid models and thus further reduce the lead times for metal part fabrication. In a manner analogous to stereolithography or selective sintering, the LENS{sup {trademark}} process builds metal parts line by line and layer by layer. Metal particles are injected into a laser beam, where they are melted and deposited onto a substrate as a miniature weld pool. The trace of the laser beam on the substrate is driven by the definition of CAD models until the desired net-shaped densified metal component is produced.

Directed Light Fabrication of Rhenium Components
Directed Light Fabrication of Rhenium Components

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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.

Laser-Based Additive Manufacturing of Metal Parts
Laser-Based Additive Manufacturing of Metal Parts

Author: Linkan Bian

Publisher: CRC Press

Published: 2017-08-09

Total Pages: 422

ISBN-13: 1351647482

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Laser-Based Additive Manufacturing (LBAM) technologies, hailed by some as the "third industrial revolution," can increase product performance, while reducing time-to-market and manufacturing costs. This book is a comprehensive look at new technologies in LBAM of metal parts, covering topics such as mechanical properties, microstructural features, thermal behavior and solidification, process parameters, optimization and control, uncertainty quantification, and more. The book is aimed at addressing the needs of a diverse cross-section of engineers and professionals.