Methods for cold spray repair
10099322 ยท 2018-10-16
Assignee
- South Dakota Board Of Regents (Pierre, SD)
- The United States Of America, As Represented By The Secretary Of The Army (Washington, DC)
Inventors
- Christian Widener (Rapid City, SD, US)
- Adam Well (Rapid City, SD, US)
- Owen Britton (Rapid City, SD, US)
- Brian James (Rapid City, SD, US)
- Rob Hrabe (Rapid City, SD, US)
- Victor Champagne (Rapid City, SD, US)
Cpc classification
Y10T29/49748
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B05B7/16
PERFORMING OPERATIONS; TRANSPORTING
B23P6/00
PERFORMING OPERATIONS; TRANSPORTING
Y10T29/49718
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B64F5/40
PERFORMING OPERATIONS; TRANSPORTING
Y10T29/49723
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
Y10T29/49746
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
International classification
B24C1/08
PERFORMING OPERATIONS; TRANSPORTING
B64F5/00
PERFORMING OPERATIONS; TRANSPORTING
B05B1/24
PERFORMING OPERATIONS; TRANSPORTING
B05B7/14
PERFORMING OPERATIONS; TRANSPORTING
B05B7/16
PERFORMING OPERATIONS; TRANSPORTING
B24C3/32
PERFORMING OPERATIONS; TRANSPORTING
B23P6/00
PERFORMING OPERATIONS; TRANSPORTING
B64F5/40
PERFORMING OPERATIONS; TRANSPORTING
Abstract
Methods for aircraft component repair and reclamation are provided. Cold spraying aircraft panels include identifying a fastener hole in an aircraft panel in need of repair, capturing the location of the fastener hole, and depositing cold spray material about the fastener hole for reclaiming the aircraft panel. Any excess material may be removed. Cold spraying hydraulic lines includes identifying a surface of the hydraulic line in need of repair, aiming a cold spray nozzle at the surface of the hydraulic line and depositing a cold spray material on the surface of the hydraulic line. Excess cold spray material may be removed as needed.
Claims
1. A method for cold spraying metal aircraft panels comprising: providing: a cold spray system comprising an enclosed dry powder source housing a dry powder, a gas source for a gas and an accelerant, and a mixing manifold, wherein the enclosed powder source has a gas source input connected in operable communication with a gas line having a gas line pressure for receiving the gas from the gas source; a gas-powder line operably connected to the dry powder source, the gas source and the mixing manifold; a gas-powder mixture outlet connected in operable communication with the gas-powder line for receiving a gas-powder mixture from within the enclosed dry powder source, wherein the gas source input and the gas-powder mixture outlet operate at the gas line pressure using the gas from the gas source; an accelerant line carrying the accelerant from the gas source and operably connected to the gas source and the mixing manifold; a cold spray gun assembly consisting of a gas-powder-accelerant mixture hose having a hose length for carrying a gas-powder-accelerant mixture a distance from the mixing manifold, an input end operably connected to the mixing manifold and an output end operably connected to a cold spray gun, wherein the cold spray gun is positionable away from the mixing manifold by extending the hose length; identifying a worn fastener hole in metal aircraft panel in need of repair, wherein the metal aircraft panel has opposite top and bottom surfaces and at least one axis of curvature following a contour of the aircraft and the worn fastener hole extends through the top and bottom surface and includes a chamfered surface formed during fabrication of the metal aircraft panel, and wherein as a result of use of the metal aircraft panel the worn fastener hole and chamfered surface include one or more dimensions outside original manufacturer dimensions and tolerances; capturing a location of the worn fastener hole; moving the cold spary gun into position adjacent the worn fastener hole without moving the mixing manifold; orienting a nozzle of a cold spray gun assembly at the worn fastener hole generally perpendicular to the chamfered surface; communicating the gas-powder-accelerant mixture from the mixing manifold through the gas-powder-accelerant mixture hose to an input side of the cold spray gun assembly; depositing cold spray material about the worn fastener hole and chamfered surface to replace metal worn away from use of the metal aircraft panel; and removing any excess cold spray material from the worn fastener hole and chamfered surface for matching the original manufacturer dimensions and tolerances.
2. The method of claim 1 further comprising: recutting a chamfer into the fastener hole by removing deposited cold spray material.
3. The method of claim 1 further comprising at least one of: a. preparing the fastener hold for cold spray adherence; b. grinding the cold spray material flush with the metal aircraft panel; c. repainting the metal aircraft panel.
4. The method of claim 1 wherein the metal aircraft panel further comprises a separate inner composite layer.
5. The method of claim 1 further comprising: directing cold spray deposition by: a. hand; b. automation.
6. The method of claim 1 wherein the metal aircraft panel and cold spray material are aluminum.
7. A method for cold spraying hydraulic lines comprising: providing: a cold spray system comprising a dry powder source housing a dry powder, a gas source for a gas and an accelerant, and a mixing manifold, wherein the powder source has a gas source input connected in operable communication with a gas line having a gas line pressure for receiving the gas from the gas source; a gas-powder line operably connected to the dry powder source for receiving the dry powder, the gas source for receiving the gas and the mixing manifold for receiving a gas-powder mixture; a gas-powder mixture outlet connected in operable communication with the gas-powder line for receiving a gas-powder mixture from within the dry powder source, wherein the gas source input and the gas-powder mixture outlet operate at the gas line pressure using the gas from the gas source; an accelerant line carrying the accelerant from the gas source and operably connected to the gas source and the mixing manifold; a cold spray gun assembly consisting of a gas-powder-accelerant mixture hose having a hose length for carrying a gas-powder-accelerant mixture from the mixing manifold a distance from the mixing manifold through the hose length, an input end operably connected to the mixing manifold and an output end operably connected to a cold spray gun, wherein the cold spray gun is positionable away from the mixing manifold and in close proximity to hydraulic line by extending the hose length; identifying a surface of a hydraulic line in need of repair; aiming the cold spray gun at the surface of the hydraulic line; depositing cold spray material onto the surface of the hydraulic line; and removing any excess cold spray material.
8. The method of claim 7 further comprising: reclaiming the hydraulic line in situ.
9. The method of claim 7 wherein the hydraulic line comprises an aircraft hydraulic line.
10. The method of claim 7 further comprising: carrying the gas-powder-accelerant mixture through the gas-powder-accelerant mixture hose to the cold spray gun from a location of the dry powder source and gas source to a separate location proximate the hydraulic line.
11. The method of claim 7 further comprising: articulating the cold spray gun by: a. hand; b. automation.
12. The method of claim 7 further comprising: mobilizing the method for making an in situ repair to the hydraulic line.
13. A cold spray repair method comprising: providing a cold spray system consisting of a dry powder source housing a dry powder, a gas source for a gas and an accelerant, and a mixing manifold, wherein the dry powder source has a gas source input connected in operable communication with a gas line from the gas source having a gas line pressure controlled by a gas controller for receiving the gas from the gas source at the gas line pressure; a gas-powder line operably connected to the dry powder source, the gas source and the mixing manifold; a gas-powder mixture outlet connected in operable communication with the gas-powder line for receiving a gas-powder mixture from within the dry powder source, wherein the gas source input and the gas-powder mixture outlet operate at the gas line pressure using the gas from the gas source; an accelerant line carrying the accelerant from the gas source and operably connected to the gas source and the mixing manifold; a cold spray gun having a gas-powder-accelerant mixture hose having a hose length for carrying a gas-powder-accelerant mixture a distance from the mixing manifold, an input end operably connected to the mixing manifold and an output end operably connected to a cold spray gun, wherein the cold spray gun is positionable away from the mixing manifold by extending the hose length; heating the gas from the gas source; moving the dray powder from the powder source through the gas-powder line at a pressure above atmospheric pressure; mixing the heated gas and the dry powder creating a heated gas-powder mixture; combining upstream before the input side of the spray gun assembly the heated gas-powder mixture with the accelerant from the gas source; communicating the gas-powder-accelerant mixture together through the gas-powder-accelerant mixture hose to the input side of the cold spray gun; and discharging the gas-powder-accelerant mixture from a discharge side of the cold spray gun onto a surface of a repair part for making a repair.
14. The method of claim 13 wherein the repair part comprises an aircraft component.
15. The method of claim 14 further comprising: repairing the aircraft component in situ while still connected to the aircraft.
16. The method of claim 13 wherein the repair part comprises an aircraft panel and the surface comprises a chamfered fastener hole.
17. The method of claim 16 further comprising: performing the repair of the chamfered fastener hole by discharging the gas-powder accelerant mixture onto the chamfered fastener hole in the aircraft panel to repair any wear.
18. The method of claim 13 wherein the repair part comprises a hydraulic line and the surface comprises an outer surface.
19. The method of claim 18 further comprising: performing the repair of the hydraulic line by discharging the gas-powder-accelerant mixture onto the outer surface of the hydraulic line to repair any wear.
20. The method of claim 13 further comprising: communicating the dry powder from the dry powder source and accelerating the heated gas-powder mixture with the accelerant from the gas source.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) Illustrative embodiments of the present invention are described in detail below with reference to the attached drawing figures, which are incorporated by reference herein and wherein:
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DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
(19) The illustrative embodiments provide methods for cold spray repair of one or more component parts. Specifically, the illustrative embodiments provide cold spray repair methods for aluminum aircraft skin fastener holes and hydraulic tubing.
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(22) According to an embodiment of the invention, a fastener hole 104 in need of repair may undergo one or more of the following operations to fully repair and reclaim the fastener hole and aircraft panel using cold spray repair methods of the present invention.
(23) Methods for cold spray repair may use any one of the cold spray methods illustrated in
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(25) Using, for example, the template created to identify the fastener 104 location and centers, machining may be performed using, for example, a micro-stop tool, to cut the chamfer 108 back into the fastener hole 104. The chamfer 108 is cut by removing portions of the cold spray material 114 and recreating the desired taper or angle of the chamfer surface 108 relative to the fastener hole 104 and outer surface 106 of the aircraft panel 100.
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Experimental Results
(28) Embodiments of the present invention can be applied specifically to a USAF B-1 bomber Forward Equipment Bay skin panel. The panel may be made from 2024-T6 aluminum. The cold spray used may be A0027 powder and compressed nitrogen at 350 psi and 350 C. After cold spray repair and reclamation, the aircraft panel 100 may be tested for adhesion, bearing load, shear force, fatigue and metallography. Regarding bearing load, experimental results of the present invention show cold spray material failure up to full bearing load (i.e., the cold spray material did not separate from the panel at a load of 5600 lbs.). Regarding shear load, a shear strength of greater than 4,000 psi was accomplished using methods of repair and reclamation of the present invention. Regarding fatigue, a 15 ksi tensile strength (which is approximately the same as the upper end for the aircraft skin loads) was used; the panel lasted approximately 500,000 cycles. Metallography microscopic results showed a dense coating with an adequate interface (see
(29) Cold Spray Repair of Hydraulic Tubing
(30) In a cold spray method shown in
(31) Embodiments of the present invention leverage cold spray methods illustrated in
(32) Embodiments of the present invention provide cold spray repair and reclamation methods that extend the life of hydraulic tubing, offering advantages over other existing approaches. Specifically, aspects of the present invention contain the principle advantage over both welding and plain spray techniques in that cold spray can create strong metallurgical bonds with the hydraulic line substrate without damaging the substrate material or surrounding components, surfaces or the like.
(33) Other advantages and aspects of cold spray repair and reclamation methods of the present invention include cold spraying hydraulic lines that are already bent into the final shape prior to cold spray being applied. The application of the cold spray does not change the final shape or orientation of the tube, to the effect that the tube can either be coated in-place (i.e., in situ) or coated after removal and then immediately reinstalled. Other advantages and aspects of the present invention include cold spraying hydraulic lines to increase the thickness only at the locations where they contact another surface, such as a clamp, bulkhead or other like object. As a result, another aspect of the present invention is that a narrower thickness hydraulic line tubing can be used in the first place (with the added width being only at the cold spray locations). Moreover, by using comparatively narrow tubing in the first place, this has the advantage that the tubing is easier to be bent into its final orientation prior to installation, and can reduce the total weight of the line in the aircraft. Other benefits include the fact that cold spray repair and reclamation of hydraulic tubing does not affect the interior wall dimensions or volume of the tubing.
(34) Specific applications of cold spray repair and reclamation of components include successful repair and reclamation of hydraulic landing gear and wing spoiler actuator lines of a USAF B-1 bomber. Specifically, a coating (e.g., titanium coating) may be applied to hydraulic lines (e.g., titanium hydraulic lines). Results successfully show adequate deposition, efficiency, bond strength, density and hardness.
Experimental Results
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(37) TABLE-US-00001 TABLE 1 Cold Spray Titanium Experimental Trials AP&C Powder Accushape Powder Tekna Powder 500 C./300 C. Helium 500 C./500 C. Helium 500 C./500 C. Helium (nozzle clogging (no nozzle clogging) (no nozzle clogging) @400 C.) Density = 95.1% Density = 99.0% Density = 92.0% Adhesion to Ti6AI4V > Adhesion to Adhesion to 10K Ti6AI4V > 10K Ti6AI4V > 10K Hardness = Hardness = Hardness = 225 Vickers 211 Vickers 212 Vickers 91.5 HRB 92.6 HRB 92.9 HRB
(38) Table 1 provides experimental results using exemplary materials, pressures and temperatures for cold spray repair and reclamation of hydraulic lines. By way of example, several powder materials are illustrated in Table 1. Testing temperatures and pressures for each powder are provided in Table 1. For example, helium at 400 psi and 500 psi may be used in the cold spray deposition repair and reclamation process. The main gas temperature may be operated at 500 C. and the powder gas temperature may be operated in between 200 C. and 500 C., by way of example. Deposition efficiencies exceed 65% and the density range for the deposition range was between 95.1% up to 99%. Hardness ranges for the deposition were between 211 and 225 Vickers. The bond strength between the hydraulic line substrate and the deposition (e.g., between 6061 aluminum and Ti6AI4V) exceeded 10,000 psi. Table 2 provides exemplary bond strength results using various exemplary powder materials on material specific substrates for the hydraulic line.
(39) TABLE-US-00002 TABLE 2 Coating Adhesion Experimental Results Powder Substrate UTS (psi) Accushape CP-Ti 6061 Aluminum 10870 11233 Glue Accushape CP-Ti Ti6AI4V 12087 11626 Glue Accushape CP-Ti 6061 Aluminum 12134 10396 Glue AP&C CP-Ti 6061 Aluminum 11703 9785 Glue AP&C CP-Ti Ti6AI4V 10128 7166 Glue AP&C CP-Ti 6061 Aluminum 6144 6196 Glue/Adhesive/ Cohesive
(40) Embodiments of the present invention provide cold spray repair and reclamation for both aluminum aircraft skin fasteners holes and hydraulic lines for aircraft, and specifically for the USAF B-1 bomber. Results successfully showed adequate deposition efficiency, bond strength, density and hardness.
(41) The illustrative embodiments provide systems and methods for repair and reclamation of aircraft skin fastener holes and hydraulic lines. Each of the embodiments may be combined in any number of combinations and such combinations are expected and utilized. The number of combinations and alternative embodiments is not limited nor intended to be limited based on the included disclosure.
(42) The previous detailed description of a small number of embodiments for implementing the invention and is not intended to be limited in scope. The following claims set forth a number of embodiments of the invention disclosed with greater particularity.