U.S. patent application number 13/907098 was filed with the patent office on 2013-12-26 for optical method for additive manufacturing of complex metallic shapes using a gaseous medium.
This patent application is currently assigned to DEEP SPACE INDUSTRIES INC.. The applicant listed for this patent is DEEP SPACE INDUSTRIES INC.. Invention is credited to STEPHEN DARRELL COVEY.
Application Number | 20130344258 13/907098 |
Document ID | / |
Family ID | 49774686 |
Filed Date | 2013-12-26 |
United States Patent
Application |
20130344258 |
Kind Code |
A1 |
COVEY; STEPHEN DARRELL |
December 26, 2013 |
OPTICAL METHOD FOR ADDITIVE MANUFACTURING OF COMPLEX METALLIC
SHAPES USING A GASEOUS MEDIUM
Abstract
The present invention is a method for additive manufacturing in
which a metal feedstock is converted to a carbonyl compound (or
other gaseous media) and then optical heat patterns are used to
direct the deposition of the contained metal into an arbitrary 3-D
structure. The optical methods used to guide the metal deposit may
include one or more laser beams acting independently or in concert,
and/or other optical technologies to apply a pattern of thermal
energy, including LCD, LED, LCoS, DLP, or even CRT projection
technologies. The metals which may be deposited are limited to
those which have compounds which are gaseous at moderate
temperatures and which decompose (to a gas and the metal) upon the
application of heat or specific chemical binding energies via
optical means. Such compounds include (but are not limited to)
nickel tetracarbonyl, iron pentacarbonyl, cobalt carbonyl, titanium
iodide, and platinum chloro-carbonyl.
Inventors: |
COVEY; STEPHEN DARRELL; (ST.
AUGUSTINE, FL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
DEEP SPACE INDUSTRIES INC. |
MCLEAN |
VA |
US |
|
|
Assignee: |
DEEP SPACE INDUSTRIES INC.
MCLEAN
VA
|
Family ID: |
49774686 |
Appl. No.: |
13/907098 |
Filed: |
May 31, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61654734 |
Jun 1, 2012 |
|
|
|
Current U.S.
Class: |
427/586 ;
118/715 |
Current CPC
Class: |
C23C 16/483 20130101;
C23C 16/16 20130101; C23C 16/4418 20130101; B33Y 70/00
20141201 |
Class at
Publication: |
427/586 ;
118/715 |
International
Class: |
C23C 18/14 20060101
C23C018/14 |
Claims
1. A system of directing the deposit of metal into a 3D structure
from a gaseous chemical compound containing a bound metal using
optically directed energy.
2. A method of (1) wherein a laser is used via a beam control
mechanism to apply energy in a direct pattern.
3. A method of (2) where the laser is used to apply thermal energy
to decompose the gas medium and deposit metal.
4. A method of (2) where the laser is used to apply chemical energy
of a specific level to excite or decompose the gas medium to
deposit metal.
5. A method of (2) where the laser energy is deposited via a raster
scanning method.
6. A method of (1) where multiple lasers are simultaneously used to
deposit metal at multiple locations.
7. A method of (1) where multiple lasers beams intersect to apply
incremental energy such that metal is only deposited where the
laser beams intersect.
8. A method of (1) where an optical imaging system (such as a CRT,
LCD, DLP, or LCoS projector) is used to direct the pattern of
heating and thus metal deposition.
9. A method of (1) where the gaseous chemical compound is a metal
carbonyl.
10. A method of (1) where the gaseous chemical compound is nickel
tetracarbonyl.
11. A method of (1) where the gaseous chemical compound is iron
pentacarbonyl.
12. A method of (1) where the gaseous chemical compound is dicobalt
octacarbonyl.
13. A method of (1) where the gaseous chemical compound is titanium
iodide.
14. A method of (1) where the gaseous chemical compound is a metal
halide.
15. A method of (1) where the metal deposit rate is limited by the
cooling of the substrate to below the decomposition temperature via
conduction through the substrate.
16. A method of (1) where the metal deposit rate is limited by the
cooling of the substrate to below the decomposition temperature via
convective cooling using a fan, blower, or other method to cause
the gaseous medium to flow past the metal deposit points.
17. A method of (1) where the byproducts of metal deposition are
continuously recycled into replacement metal gas compound(s).
18. A method of (9) where the carbon monoxide produced by the
decomposition of the metal carbonyl is continuously recycled into
fresh metal carbonyl.
19. A system of directing the deposit of metal from a gaseous
chemical compound containing a bound metal using optically directed
energy around non-metallic or dissimilar metal parts, incorporating
these into the metal product.
20. A system of directing the deposit of metal (a weld) into a gap
between two parts to be joined or into a fracture or crack of a
part to be repaired from a gaseous chemical compound containing a
bound metal using optically directed energy.
Description
BACKGROUND OF THE INVENTION
[0001] Traditional manufacturing methods are subtractive, meaning
that a material or a group of materials must be removed until a
desired product remains. Subtractive and traditional manufacturing
and machining processes thus produce a significant amount of wasted
material. More recently, additive manufacturing methods have become
increasingly popular. In additive manufacturing, a material is
deposited on a substrate to form a desired object. Additive
manufacturing methods only deposit material needed to manufacture
the product, and thus do not waste materials. Detailed computer
assisted design (CAD) instructions can be input into additive
manufacturing machines to create complex manufactured objects of
very high complexity and quality.
[0002] It is therefore an object of the present invention to
provide an additive manufacturing system and method that makes use
of a common metal feedstock that can be converted to a carbonyl
vapor (or other gaseous media) through a sublimation process. It is
a further object of the present invention to deposit the metal from
the carbonyl (or other) vapor according to an advanced CAD design
process and then cool the substrate so that the metal vapor forms
into the desired shape and structure.
BRIEF SUMMARY OF THE INVENTION
[0003] The Invention produces high density, high strength, high
quality nickel (or other) metal parts. Some existing 3D metal
printing technologies produce parts by laser sintering of metal
powders, often using easily-melted coatings (solder) over stronger
grains to avoid the necessity of completely melting the bulk metal,
such as stainless steel powder. This process results in porous
structures whose strength is limited by the soldering metal. Other
existing 3D metal printing technologies extrude metal through a
print head which melts it, essentially building up a product out of
layers of melted metal. These products use low-melting-point, soft
metals due to limitations of the printer heads, and thus can not be
used to create high-strength, high-temperature-capable parts. The
Invention uses a relatively low-temperature process wherein a
gaseous medium containing the metal is heated via lasers or other
optical patterning mechanisms to decompose the gas and deposit the
metal at the heated point. The laser beam (in the preferred
embodiment) is manipulated to transcribe a pattern of heat, the
metal deposits into that pattern, and the pattern is changed with
time such that a desired 3D product is produced from computer
resident design specifications (3D Computer Aided Design).
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] FIG. 1 represents a flow diagram of a process and apparatus
depicting the invention.
DETAILED DESCRIPTION OF THE DRAWINGS
[0005] In order that the invention be better understood, a
preferred embodiment will now be described (by way of example only)
wherein FIG. 1 represents a flow diagram of a process and apparatus
depicting the invention. The components described in FIG. 1 are:
[0006] 1. A Carbon Monoxide supply tank (with valve and pressure
regulator) [0007] 2. The Reaction Chamber, which contains a charge
of nickel metal powder, a mechanism to resupply the nickel (not
depicted), filters (not depicted) at the input and output to
prevent the flow of powders out of the chamber, and a temperature
control mechanism to heat the contents to specified temperatures.
[0008] 3. A flow control valve left open during normal operation.
[0009] 4. A condensing coil to convert warm metal carbonyl gas to a
liquid. [0010] 5. A chamber to separate unreacted carbon monoxide
gas from metal carbonyl liquid, collecting the liquid for
subsequent use. [0011] 6. A pump to recycle carbon monoxide gas
through the Reaction Chamber (2). [0012] 7. A valve to trickle
metal carbonyl liquid into the Drip Pan (11) of the Deposit Chamber
(10). [0013] 8. A valve, open during normal operation to recycle
carbon monoxide gas from its production in the Deposit Chamber
(10). [0014] 9. A valve, closed during normal operation, but open
during safing operation. [0015] 10. The Deposit Chamber which is a
temperature controlled pressure chamber, with an access door or
panel (17), where the metal printing takes place. [0016] 11. A Drip
Pan, which accepts the liquid metal carbonyl admitted via valve
(7), and holds it as the liquid is vaporized. [0017] 12. A
Recirculating Fan or Blower, which serves to distribute the metal
carbonyl vapors throughout the Deposit Chamber, and also to provide
a cooling flow to keep the substrates and previously deposited
material below the metal carbonyl decomposition temperature. [0018]
13. A Printing Platform or plate, onto which the output product is
3D printed. It is composed of an unspecified material which
conducts heat away from the deposit points while also being a
non-stick material such that the output product may be easily
removed. [0019] 14. The Print Area which is targetable by the laser
beam(s) (or other optical heat patterning technology) and thus
defines the maximum horizontal extents which may be printed. It may
be as large as the entire Printing Platform (13). [0020] 15. The
Laser Beam (or other optical) heat source which controls the
pattern of metal deposit. [0021] 16. The Laser Window, which admits
the Laser Beam (15) into the Deposit Chamber (10). It is composed
of quartz or another material which is optically flat and
transparent to the chosen laser wavelength. [0022] 17. The Access
Door (or, as depicted, the Access Portal) which is a glass, quartz,
or other material to monitor the progress of the 3D Printing
Process. Note that it may be replaced via a solid door and interior
camera in some embodiments. [0023] 18. The Neutralizing Chamber
which converts potentially toxic gases such as carbon monoxide and
metal carbonyl into harmless substances, implemented in this
embodiment as a heated catalytic converter. [0024] 19. A valve
and/or pressure regulator to dump output or waste gases to the
exterior in a controlled fashion. [0025] 20. A Laser Beam
Controller, used to direct the X-Y position of the laser beam, as
well as its focal depth. This controller converts the commands of a
connected computer (not depicted) into beam position, and thus
directs the 3D printing pattern. [0026] 21. A Laser Beam
(wavelength and technology chosen for efficiency and ease of use),
generally several to several tens of watts of output power, which
may be controlled by the connected computer (not depicted). When
wavelengths and powers chosen are not eye-safe, the laser will have
additional safety interlocks to prevent its operation except under
controlled conditions. [0027] 22. A tank of a neutral gas to flush
the chambers of the apparatus during safing (or initializing)
operations. It is equipped with a valve and pressure regulator. NOT
DEPICTED: temperature control mechanisms for the Reaction Chamber
(2), Condensing Coil (4), Collection Chamber (5), Deposit Chamber
(10), or Neutralizing Chamber (18); pressure and temperature
sensors; laser beam safety shrouds around the beam exterior to the
Deposit Chamber; the Laser Scanner which monitors the progress of
the 3D printing; or the computer that converts a Computer Aided
Design (CAD) document into commands for the laser and beam
controller while monitoring chamber conditions.
DETAILED DESCRIPTIONS OF THE INVENTION
I. A General Explanation of the Invention and How to Practice
It
[0028] The present invention is a new method for an additive
manufacturing process of complex metallic shapes utilizing advanced
computer assisted design. The process of the present invention
deposits metal from a vapor in a precise 3d shape. Using a metal
source feedstock, a unique laser (or other optical patterning
method) to metal carbonyl (or other gas) vapor process allows for a
new method of 3d printing. The metal deposition on a cold substrate
is mediated directed by laser raster (or other optical) heating (or
energy deposit) to build a free form object using a CAD design
process to measure and observe the process.
[0029] The present invention seeks to create a unique additive
manufacturing capability utilizing common metallic feedstock which
is then sublimated by conversion to carbonyl gas and then
subsequently deposited by using modifications of known 3d printing
processes. By utilizing metal carbonyl vapor (or other gas) and an
advanced multi-variable laser system driven by advanced CAD
algorithmic software, the present invention allows for a new class
of additive manufacturing machinery.
[0030] In addition, the low temperature of the metal additive
process (well below the melting point) enables several additional
capabilities:
[0031] 1) Other components and materials may be incorporated into
output products, such as gaskets, bearings, insulators, or any
other type of material that can withstand the modest (250 degrees
C. or lower) temperatures,
[0032] 2) Metal parts may be welded together by using (for example)
a laser to direct heat into a crevice or other gap, causing the
deposition of metal in that gap to effect a weld. The relatively
low temperature of the process enables dissimilar metals to be
potentially welded, as the differing coefficient of thermal
expansion will not be as much of an issue as with normal
high-temperature (molten metal) welding.
[0033] In the preferred embodiment, the present invention comprises
the following machinery components:
[0034] 1. A metal carbonyl (or other gas wherein the metal is
chemically bound) production system
[0035] 2. A variable vapor delivery and pressure to provide active
temperature control
[0036] 3. A substrate cooling system
[0037] 4. A laser rastering (multiple) An optical patterning and
metal deposit sensor system
[0038] 5. A carbon monoxide (or other reagent)CO) and vapor
recovery mechanical system
[0039] Although the invention has been explained in relation to its
preferred embodiment, it is to be understood that many other
possible modifications and variations can be made without departing
from the spirit and scope of the invention as herein described.
II. Detailed Description of the Apparatus and Operation
[0040] Note that the following description is an example of the
process, described as to the specific active gas Nickel
Tetracarbonyl Ni(CO)4 and the 3D printing of nickel metal parts
using a single laser. Alternative embodiments are described in the
claims.
[0041] The process begins with the production of Ni(CO)4 by
circulating carbon monoxide (CO) gas from tank (1) through a source
of warm (130.degree. C.) nickel powder (in the Reaction Chamber
(2)), which is condensed (4) at room temperature (25.degree. C.)
and collected as a liquid in the Collection Chamber (5). Then, the
purified Ni(CO)4 is piped through valve (7) into the warm Drip Pan
(11) in the Deposit Chamber (10) where it evaporates and a laser
beam (15) generates hot spots onto a substrate (13). The hot spots
cause the Ni(CO)4 to decompose into metallic nickel (which
immediately deposits) and CO gas. The CO gas/Ni(CO)4 gas mixture is
recycled through the Collection Chamber (5) via open valve (8)
which serves to condense and regenerate the Ni(CO)4 by circulating
the CO through the Reaction Chamber (2).
[0042] The operational process is as follows: [0043] Setup (initial
cleansing) [0044] Close exhaust valve (19) only and pump down to
vacuum [0045] OR open all valves and flush with nitrogen from tank
(22) with CO pump (6) running [0046] Fill chambers with CO (Carbon
Monoxide) from tank (1) [0047] Generate Ni(CO)4 [0048] Enable
heaters bringing Reaction Chamber (2) to 150.degree. C., Deposit
Chamber (10) to 50.degree. C., and Neutralizing Chamber (18) to
350.degree. C. [0049] Operate CO Pump (6) with valve (3) open and
valves 7, 8, 9, and 19 closed. [0050] Add CO as required to
maintain target pressure (automatic via regulator valve on tank 1)
[0051] Stop when desired volume of liquid Ni(CO)4 accumulates
[0052] Operate [0053] Open drip valve 7 to deliver liquid Ni(CO)4
into drip pan 11 in Deposit Chamber (10). Open valve 8, and set
pressure regulator/valve 19 to exhaust gases in case of
overpressure condition. Turn on blower (12). [0054] Use computer
(not depicted) to convert 3D schematic into control signals for the
Laser (21) and beam controller (20) to transcribe desired pattern
onto substrate 13 while monitoring temperatures and pressures of
chambers, substrate plate, and laser-heated spots if possible.
Separate Laser Scanner (not depicted) is used to monitor progress
to insure correct depth of metal deposit. [0055] Byproduct CO gas,
passing into the recirculating Reaction Chamber circuit, will
regenerate Ni(CO)4 in Reaction Chamber (2) as replacement pure
liquid Ni(CO)4 will drip into the Deposit Chamber. [0056] Stop when
sample part is complete [0057] Open Deposition Chamber [0058] Close
drip valve (7) and valve 3, open valve 9 and allow liquid Ni(CO)4
to accumulate in Collection Chamber (5) until most Ni(CO)4 has been
collected. [0059] Close all valves and evacuate reaction chamber
using vacuum pump (not depicted), then fill with nitrogen gas
[0060] OR close all valves except exhaust valve 19 which is set to
"full open" (no pressure regulation), then flush with nitrogen gas
to pass remaining gases through Neutralizing Chamber 18. [0061]
Open Deposition Chamber Door (17) and remove part [0062] Neutralize
(used to "safe" the apparatus for transportation or storage) [0063]
Set Reaction Chamber (2) to 250.degree. C. and Collection Chamber
(5) to 50.degree. C. (which will vaporize any remaining
Ni(CO).sub.4), operate CO Pump (6) until all Ni(CO)4 has decomposed
into nickel powder in Reaction Chamber (2), then evacuate or flush
CO with nitrogen through Neutralizing Chamber (18).
* * * * *