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Title: Near Net Shape production of metal components using LENS

Abstract

Rapid Prototyping and Near Net Shape manufacturing technologies are the subject of considerable attention and development efforts. At Sandia National Laboratories, one such effort is LENS (Laser Engineered Net Shaping). The LENS process utilizes a stream of powder and a focused Nd YAG laser to build near net shape fully dense metal parts. In this process, a 3-D solid model is sliced, then an X-Y table is rastered under the beam to build each slice. The laser 1 powder head is incremented upward with each slice and the deposition process is controlled via shuttering of the laser. At present, this process is capable of producing fully dense metal parts of iron, nickel and titanium alloys including tool steels and aluminides. Tungsten components have also been produced. A unique aspect of this process is the ability to produce components wherein the composition varies at differing locations in the part. Such compositional variations may be accomplished in either a stepped or graded fashion. In this paper, the details of the process will be described. The deposition mechanism will be characterized and microstructures and their associated properties will be discussed. Examples of parts which have been produced will be shown and issues regardingmore » dimensional control and surface finish will be addressed.« less

Authors:
; ; ; ; ;  [1];  [2]
  1. Sandia National Labs., Albuquerque, NM (United States)
  2. Sandia National Labs., Livermore, CA (United States)
Publication Date:
Research Org.:
Sandia National Labs., Albuquerque, NM (United States)
Sponsoring Org.:
USDOE Assistant Secretary for Management and Administration, Washington, DC (United States); USDOE Office of Financial Management and Controller, Washington, DC (United States)
OSTI Identifier:
650377
Report Number(s):
SAND-98-0664C; CONF-980716-
ON: DE98005030; BR: YN0100000; TRN: AHC2DT04%%291
DOE Contract Number:
AC04-94AL85000
Resource Type:
Conference
Resource Relation:
Conference: 3. Pacific Rim international conference on advanced materials and processing, Honolulu, HI (United States), 12-16 Jul 1998; Other Information: PBD: Mar 1998
Country of Publication:
United States
Language:
English
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; 36 MATERIALS SCIENCE; COMPUTER-AIDED MANUFACTURING; POWDERS; LASER RADIATION; ALLOYS; MICROSTRUCTURE; COMPUTER-AIDED DESIGN; SOLID STATE LASERS; MELTING; SURFACE COATING

Citation Formats

Schlienger, E., Dimos, D., Griffith, M., Michael, J., Oliver, M., Romero, T., and Smugeresky, J. Near Net Shape production of metal components using LENS. United States: N. p., 1998. Web.
Schlienger, E., Dimos, D., Griffith, M., Michael, J., Oliver, M., Romero, T., & Smugeresky, J. Near Net Shape production of metal components using LENS. United States.
Schlienger, E., Dimos, D., Griffith, M., Michael, J., Oliver, M., Romero, T., and Smugeresky, J. Sun . "Near Net Shape production of metal components using LENS". United States. doi:. https://www.osti.gov/servlets/purl/650377.
@article{osti_650377,
title = {Near Net Shape production of metal components using LENS},
author = {Schlienger, E. and Dimos, D. and Griffith, M. and Michael, J. and Oliver, M. and Romero, T. and Smugeresky, J.},
abstractNote = {Rapid Prototyping and Near Net Shape manufacturing technologies are the subject of considerable attention and development efforts. At Sandia National Laboratories, one such effort is LENS (Laser Engineered Net Shaping). The LENS process utilizes a stream of powder and a focused Nd YAG laser to build near net shape fully dense metal parts. In this process, a 3-D solid model is sliced, then an X-Y table is rastered under the beam to build each slice. The laser 1 powder head is incremented upward with each slice and the deposition process is controlled via shuttering of the laser. At present, this process is capable of producing fully dense metal parts of iron, nickel and titanium alloys including tool steels and aluminides. Tungsten components have also been produced. A unique aspect of this process is the ability to produce components wherein the composition varies at differing locations in the part. Such compositional variations may be accomplished in either a stepped or graded fashion. In this paper, the details of the process will be described. The deposition mechanism will be characterized and microstructures and their associated properties will be discussed. Examples of parts which have been produced will be shown and issues regarding dimensional control and surface finish will be addressed.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Mar 01 00:00:00 EST 1998},
month = {Sun Mar 01 00:00:00 EST 1998}
}

Conference:
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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 layermore » 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 cm{sup 3}/hr with 12 cm{sup 3}/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.« less
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