WO2015006420A1

WO2015006420A1 - Vented plated polymer

Info

Publication number: WO2015006420A1
Application number: PCT/US2014/045911
Authority: WO
Inventors: Glenn Levasseur; Joseph Parkos; Grant O. COOK, III; Charles R. Watson
Original assignee: United Technologies Corporation
Priority date: 2013-07-09
Filing date: 2014-07-09
Publication date: 2015-01-15
Also published as: US20160251760A1; CA2917875A1

Abstract

A vented plated polymer component is disclosed. The vented plated polymer component may comprise a polymer substrate, a metal plating deposited on a surface of the polymer substrate, and at least one vent formed through the metal plating. The at least one vent may extend from an outer surface of the metal plating to the surface of the polymer substrate, and it may be sized to allow an escape of a gas from the polymer substrate to an external environment surrounding the plated polymer component.

Description

VENTED PLATED POLYMER

Cross-Reference to Related Applications

[0001] This application claims priority under 35 U.S. C. § 119(e) to U.S. Provisional Patent Application Serial Number 61/844,108 filed on July 9, 2013.

Field of the Disclosure

[0002] The present disclosure generally relates to plated polymers. More specifically, this disclosure relates to plated polymer components having vents for outgassing during high- temperature events.

Background

[0003] Lightweight polymer materials continue to be explored for use in gas turbine engine applications to reduce the overall weight of the engine and improve engine efficiency and fuel savings. However, due to the high temperatures and stresses encountered in many parts during engine operations, the use of many polymeric materials have been restricted to cooler parts of the engine, such as external parts of the engine. When polymeric materials are exposed to high temperatures, they tend to outgas, releasing gases from the polymer substrate to the external environment. However, in plated polymeric structures in which the outer surfaces of the polymer substrate are encapsulated in (or blocked by) a metal plating, such outgassing is inhibited and may lead to significant expansion of the polymer substrate and possible defects in the metal plating as well as in the structure of the part as a whole. To provide performance characteristics necessary for the safe use of lightweight polymer materials in a broader range of gas turbine engine parts, especially those parts that may experience very high temperatures in the event of a fire, enhancements are needed to improve the high-temperature stability of plated polymeric components. SUMMARY OF THE DISCLOSURE

[0004] In accordance with one aspect of the present disclosure, a plated polymer component is disclosed. The plated polymer component may comprise a polymer substrate and a metal plating deposited on a surface of the polymer substrate. The plated polymer component may further comprise at least one vent formed through the metal plating.

[0005] In another refinement, the at least one vent may extend from an outer surface of the metal plating to the surface of the polymer substrate.

[0006] In another refinement, the at least one vent may be sized to allow an escape of a gas from the polymer substrate to an external environment surrounding the plated polymer component.

[0007] In another refinement, the polymer substrate may be fully encapsulated in the metal plating.

[0008] In another refinement, the plated polymer component may have a fireproof side and a weakened side, and the at least one vent may be localized on the weakened side of the plated polymer component.

[0009] In another refinement, the escape of the gas from the polymer substrate may occur through the weakened side of the plated polymer component.

[0010] In another refinement, the at least one vent may have a diameter in the range of about 0.8 mm to about 6.4 mm.

[0011] In another refinement, the at least one vent may be normal to the outer surface of the metal plating.

[0012] In another refinement, the at least one vent may be oriented at an oblique angle with respect to the outer surface of the metal plating.

[0013] In accordance with another aspect of the present disclosure, a method for fabricating a plated polymer component is disclosed. The method may comprise forming a polymer substrate, and depositing a metal plating on a surface of the polymer substrate. The method may further comprise forming at least one vent through the metal plating such that the at least one vent extends from an outer surface of the metal plating to the surface of the polymer substrate.

[0014] In another refinement, forming the at least one vent through the metal plating may comprise forming the at least one vent on a weakened side of the plated polymer component.

[0015] In another refinement, forming the at least one vent through the metal plating may comprise drilling or machining the at least one vent through the metal plating.

[0016] In another refinement, depositing the metal plating on the surface of the substrate may comprise: 1) preparing the surface of the polymer substrate for receiving a catalyst, 2) activating the surface of the polymer substrate by depositing the catalyst on the surface of the polymer substrate, 3) depositing a first layer on the catalyst by electroless deposition, 4) depositing a second conductive layer on the first layer by electrolytic deposition, and 5) depositing the metal plating on the second layer.

[0017] In another refinement, forming the at least one vent through the metal plating may comprise introducing a contaminant onto the surface of the polymer substrate prior to or after depositing a second layer on the first layer by electrolytic deposition.

[0018] In another refinement, the contaminant may be selected from the group consisting of an oil and an overconductive paint.

[0019] In accordance with another aspect of the present disclosure, a plated polymer component is disclosed. The plated polymer component may have a polymer substrate, a metal plating deposited on a surface of the polymer substrate, and at least one vent formed through the metal plating. The plated polymer component may be fabricated by a method comprising: 1) forming the polymer substrate, 2) depositing the metal plating on the surface of the polymer substrate, and 3) forming the at least one vent through the metal plating such that the at least one vent extends from an outer surface of the metal plating to the surface of the polymer substrate.

[0020] In another refinement, forming the at least one vent through the metal plating may comprise forming the at least one vent on a weakened side of the plated polymer component.

[0021] In another refinement, forming the at least one vent through the metal plating may comprise drilling or machining the at least one vent through the metal plating.

[0022] In another refinement, depositing the metal plating on the surface of the substrate may comprise: 1) preparing the surface of the polymer substrate for receiving a catalyst, 2) activating the surface of the polymer substrate by depositing the catalyst on the surface of the polymer substrate, 3) depositing a first layer on the catalyst by electroless deposition, 4) depositing a second conductive layer on the first layer by electrolytic deposition, and 5) depositing the metal plating on the second layer.

[0023] In another refinement, forming the at least one vent through the metal plating may comprise introducing a contaminant onto the surface of the polymer substrate prior to or after depositing a second layer on the first layer by electrolytic deposition.

[0024] These and other aspects and features of the present disclosure will be more readily understood when read in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] FIG. 1 is a front view of a vented plated polymer component constructed in accordance with the present disclosure.

[0026] FIG. 2 is a cross-sectional view of the vented plated polymer component of FIG. 1 taken along the line 2-2 of FIG. 1, constructed in accordance with the present disclosure.

[0027] FIG. 3 is a cross-sectional view of a vented plated polymer component similar to FIG. 2, but having a fireproof side and a weakened side, constructed in accordance with the present disclosure. [0028] FIG. 4 is a flow chart diagram illustrating steps involved in the fabrication of the vented plated polymer component in accordance with a method of the present disclosure.

[0029] It should be understood that the drawings are not necessarily drawn to scale and that the disclosed embodiments are sometimes illustrated schematically and in partial views. It is to be further appreciated that the following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses thereof. In this regard, it is to be additionally appreciated that the described embodiment is not limited to use for certain applications. Hence, although the present disclosure is, for convenience of explanation, depicted and described as certain illustrative embodiments, it will be appreciated that it can be implemented in various other types of embodiments and in various other systems and environments.

DETAILED DESCRIPTION

[0030] FIGs. 1 and 2 illustrate a vented plated polymer component 180 in accordance with the present disclosure. The vented plated polymer component 180 may be characterized by high structural robustness and an ability to maintain its structure at high temperatures, such as those experienced in certain high-temperature regions or fire zones of a gas turbine engine. In this regard, the component 180 may be a structural component of a gas turbine engine requiring high strength and high-temperature resistance such as, but not limited to ducts or covers in fire zones of the gas turbine engine. Alternatively, it may be employed as a structural or operative component for use in another application requiring parts with high structural and temperature stability. Moreover, although depicted as an exemplary box-like structure for clarity purposes, the component 180 may have any structure suitable for its use, whether simple or complex.

[0031] The vented plated polymer component 180 may consist of a polymer substrate 182 having one or more metal platings 184 applied to one or more of the outer surfaces of the polymer substrate 182, as best shown in FIG. 2. As one possibility, the polymer substrate 182 may be fully encapsulated in the metal plating 184, as shown in FIG. 2. The metal plating 184 may contribute substantially to the overall structural resilience of the component 180.

[0032] Importantly, the metal platings 184 may have one or more vents 185 which may penetrate through the thickness of the metal plating 184 from an outer surface 186 of the component 180 to at least the outer surface of the polymer substrate 182, as shown in FIG. 2. The vents 185 may permit the escape of gases (or outgassing) from the polymer substrate 182 to the external environment when the component 180 is exposed to high temperatures, such as a during a fire event. Therefore, the vents 185 may assist in preventing expansion of the polymer substrate 182 as well as resulting structural distortion of the metal plating 184 which may otherwise occur if such outgassing were blocked by solid metal plating layers.

[0033] The vents 185 may be localized in certain areas or selected outer surfaces of the component 180 in defined or irregular patterns, or they may be more evenly distributed over all of the outer surfaces 186 of the component 180 in defined or irregular patterns.

Furthermore, venting features may be installed on selected outer surfaces of the component 180 to provide controlled venting on one side of the component which is not structurally limiting during a high temperature or fire event (see FIG. 3 and further details below). The diameter of the vents 185 may be in the range of about 0.031 inches (about 0.79 mm) to about 0.25 inches (about 6.4 mm), but other diameters may also suffice. In addition, the vents 185 may be normal to the outer surface 186 of the component 180, as shown in FIG. 2, or may be oriented at variable oblique angles with respect to the outer surface 186. The vents 185 may be introduced into the metal plating 184 by laser drilling, machine drilling, or another comparable method selected by a skilled artisan. Alternatively, the vents 185 may be incorporated into the metal plating 184 by the introduction of contaminants onto the outer surfaces of the polymer substrate 182 to cause defects and the formation of voids or pores in the metal plating 184 during its deposition (see FIG. 4 and further details below). As yet another alternative method, masking may be used to block certain surfaces of the polymer substrate 182 during deposition of the metal plating 184, as will be understood by those skilled in the art.

[0034] The metal plating 184 may consist of one or more platable materials such as, but not limited to nickel, cobalt, copper, iron, gold, silver, palladium, rhodium, chromium, and alloys with any of the foregoing elements comprising at least 50 wt.% of the alloy, and combinations thereof. The metal plating 184 may also have a thickness in the range of about 0.001 inches (about 0.0254 mm) to about 0.050 inches (about 1.27 mm), although other thicknesses may also apply. The polymer substrate 182 may be formed from a thermoplastic material or a thermoset material. Suitable thermoplastic materials may include, but are not limited to, polyetherimide (PEI), thermoplastic polyimide, polyether ether ketone (PEEK), polyether ketone ketone (PEKK), polysulfone, polyamide, polyphenylene sulfide, polyester, polyimide, and combinations thereof. Suitable thermoset materials may include, but are not limited to, condensation polyimides, addition polyimides, epoxy cured with aliphatic and/or aromatic amines and/or anhydrides, cyanate esters, phenolics, polyesters, polybenzoxazine, polyurethanes, polyacrylates, polymethacrylates, silicones (thermoset), and combinations thereof. Optionally, the polymer substrate 182 may also include one or more structurally reinforcing components such as carbon fibers, glass fibers, or structurally reinforcing nanomaterials or metals.

[0035] As one possible arrangement for situations where the component 180 is required to maintain its structural integrity during a high temperature event or a fire event, the component 180 may be designed to have a fireproof side 188 and a weakened side 190, as best shown in FIG. 3. The operative structure of the component 180 may be dependent on the structural integrity of the fireproof side 188, whereas the weakened side 190 may be at least somewhat structurally expendable. The fireproof side 188 may lack the vents 185 and may be strong enough to retain its structure in the case of a high temperature event. For example, the fireproof side 188 may have thicker metal plating walls than the weakened side 190 or it may have other design features that enable it to resist heat-induced structural failure. In contrast, the weakened side 190 may have one or more of the vents 185 to allow

outgassing from the polymer substrate 182 during high temperature events. The component 180 may be positioned such that the fireproof side 188 is oriented towards a fireproof zone 192 (where a fire or other high-temperature event may occur) and the weakened side 190 is oriented towards a non-fireproof zone 195 (where fires or other high-temperature events may not occur), as shown. During a fire or other high-temperature event, this arrangement may allow the preferential venting and/or structural failure at the weakened side 190 (non- structurally limiting side) instead of at the structural fireproof side 188 such that the component 180 may retain its operative structure during the high-temperature event.

[0036] FIG. 4 illustrates a method of fabricating vented plated polymer components in accordance with this disclosure. According to a first block 197, the polymer substrate 182 may be formed from the thermoplastic or thermoset materials described above (including optional reinforcing components) in a desired shape by a method apparent to a skilled artisan such as, but not limited to, injection molding, compression molding, blow molding, additive manufacturing (liquid bed, powder bed, deposition processes), or composite layup (autoclave, compression, or liquid molding). According to a next block 199, outer surfaces of the polymer substrate 182 selected for plating with the metal plating 184 may then be prepared for activation with a catalyst by etching, surface abrasion, ionic activation, or other mechanical or chemical surface activation process. Such surface preparation may promote adhesion of the catalyst to the selected outer surfaces of the polymer substrate 182. The prepared surfaces of the polymer substrate 182 may then be activated by deposition of the catalyst on the selected outer surfaces according to a block 201, as shown. The catalyst may assist in promoting attachment of metals onto the selected outer surfaces of the polymer substrate 182. The catalyst may be a palladium layer having an atomic-scale thickness, although other suitable catalysts and/or other layer thicknesses may also be used.

[0037] Electroless (current-free) deposition of a first layer on the catalyst layer followed by electrolytic deposition of a second layer layer on the first layer may then be carried out according to a block 203 and a block 205, respectively. The first layer may be a nickel layer and the second layer may be a copper layer, although other suitable metals may also suffice. The nickel layer may have a thickness of about one micron (about 0.001 mm) and the copper layer may have a thickness in the range of about 0.0001 inches to about 0.001 inches (about 0.0025 mm to about 0.025 mm), however, other nickel-layer and copper-layer thicknesses may also be used. The methods of electroless metal deposition and electrolytic metal deposition required for the performance of the blocks 203 and 205 will be apparent to those having ordinary skill in the art. Notably, following the block 205, the treated outer surfaces of the polymer substrate 182 may exhibit the surface characteristics of a metal (e.g., conductivity), thereby allowing the electrolytic deposition of the metal plating layer 184 thereon.

[0038] As one possible method to create the vents 185 in the component 180, contaminants may be introduced onto the selected outer surfaces of the polymer substrate 182 according to an optional block 204, as shown. The block 204 may be performed either prior to or after the block 205, as shown. The contaminants may be contaminants which adhere to the outer surfaces of the polymer substrate 182 and may include contaminants such as, but not limited to, oils or overconductive paints such as a conductive paint or adhesive. The contaminants may create the vents 185 by at least partially attenuating the surface conductivity of the polymer substrate 182, thereby reducing or preventing the adherence of metal ions to the outer surfaces of the polymer substrate during electrolytic deposition steps. In this way, defects including voids and/or pores (vents 185) may be created in the component 180.

Masking may also be used to perform the same function as described above for the contaminants, as will be understood by those skilled in the art.

[0039] Following the block 205, deposition of the metal plating 184 may be carried out according to a block 207, as shown. Deposition of the metal plating 184 may be performed using metal deposition techniques apparent to those skilled in the art including, but not limited to, electrolytic plating, electroless plating, or electro forming. The metal composition of the metal plating 184 may be selected from those platable materials listed above.

Following deposition of the metal plating 184, additional metal plating layers having the same or different compositions may be deposited, if desired, by electrolytic plating or another metal deposition method. As another possible method to create the vents 185 in the component, the vents 185 may be formed in the metal plating(s) 184 according to a block 209 after the metal plating 184 layer(s) have been deposited. As one possibility, the vents 185 may be formed in the metal plating 184 by drilling. Possible drilling techniques may include laser drilling, machine drilling, or another comparable drilling method selected by a skilled artisan. It is noted that the vents 185 may be created by either or both of the blocks 204 and 209.

Industrial Applicability

[0040] In summary, it can therefore be seen that vented plated polymer components as disclosed herein may find wide applicability in many areas including, but not limited to, heat- and fire-resistant component fabrication for gas turbine engines. As disclosed herein, the polymer support structure may be formed from a lightweight polymer and the metal plating applied to its surfaces may substantially contribute to the structural resilience of the component. The introduction of vents in the metal plating layer may allow the polymeric substrate to outgas when exposed to high temperatures, thereby preventing resulting structural distortion of the metal plating layer. Moreover, the vents may be strategically introduced in a non-structurally limiting zone of the component to drive controlled failure or venting of the weakened zone during a high-temperature event. The invention described herein may also find wide industrial applicability in a wide range of areas such as, but not limited to, aerospace and automotive industries.

Claims

WHAT IS CLAIMED IS:

1. A plated polymer component, comprising:

a polymer substrate;

a metal plating deposited on a surface of the polymer substrate; and at least one vent formed through the metal plating.

2. The plated polymer component of claim 1, wherein the at least one vent extends from an outer surface of the metal plating to the surface of the polymer substrate.

3. The plated polymer component of claim 2, wherein the at least one vent is sized to allow an escape of a gas from the polymer substrate to an external environment surrounding the plated polymer component.

4. The plated polymer component of claim 3, wherein the polymer substrate is fully encapsulated in the metal plating.

5. The plated polymer component of claim 3, wherein the plated polymer component has a fireproof side and a weakened side, and wherein the at least one vent is localized on the weakened side of the plated polymer component.

6. The plated polymer component of claim 5, wherein the escape of the gas from the polymer substrate occurs through the weakened side of the plated polymer component.

7. The plated polymer component of claim 3, wherein the at least one vent has a diameter in the range of about 0.8 mm to about 6.4 mm.

8. The plated polymer component of claim 3, wherein the at least one vent is normal to the outer surface of the metal plating.

9. The plated polymer component of claim 3, wherein the at least one vent is oriented at an oblique angle with respect to the outer surface of the metal plating.

10. A method for fabricating a plated polymer component, comprising:

forming a polymer substrate; depositing a metal plating on a surface of the polymer substrate; and forming at least one vent through the metal plating such that the at least one vent extends from an outer surface of the metal plating to the surface of the polymer substrate.

11. The method of claim 10, wherein forming the at least one vent through the metal plating comprises forming the at least one vent on a weakened side of the plated polymer component.

12. The method of claim 10, wherein forming the at least one vent through the metal plating comprises drilling or machining the at least one vent through the metal plating.

13. The method of claim 10, wherein forming the at least one vent comprises masking a surface of the polymer substrate while depositing the metal plating on the surface of the polymer substrate to create the at least one vent.

14. The method of claim 13, wherein forming the at least one vent through the metal plating comprises introducing a contaminant onto the surface of the polymer substrate prior depositing the metal plating on the surface of the substrate.

15. The method of claim 14, wherein the contaminant is selected from the group consisting of an oil and an overconductive paint.

16. A plated polymer component having a polymer substrate, a metal plating deposited on a surface of the polymer substrate, and at least one vent formed through the metal plating, the plated polymer component being fabricated by a method comprising:

forming the polymer substrate;

depositing the metal plating on the surface of the polymer substrate; and forming the at least one vent through the metal plating such that the at least one vent extends from an outer surface of the metal plating to the surface of the polymer substrate.

17. The plated polymer component of claim 16, wherein forming the at least one vent through the metal plating comprises forming the at least one vent on a weakened side of the plated polymer component.

18. The plated polymer component of claim 16, wherein forming the at least one vent through the metal plating comprises drilling or machining the at least one vent through the metal plating.

19. The plated polymer component of claim 16, wherein depositing the metal plating on the surface of the substrate comprises:

preparing the surface of the polymer substrate for receiving a catalyst;

activating the surface of the polymer substrate by depositing the catalyst on the surface of the polymer substrate;

depositing a first layer on the catalyst by electroless deposition; depositing a second layer on the first layer by electrolytic deposition, the second layer being conductive; and

depositing the metal plating on the second layer.

20. The plated polymer component of claim 19, wherein forming the at least one vent through the metal plating comprises introducing a contaminant onto the surface of the polymer substrate prior to or after depositing the second layer on the first layer by electrolytic deposition.