TECHNICAL FIELD Various embodiments of the present disclosure relate generally to the field of electroplating and, more particularly, to electroplated structures and methods of fabricating the same.
BACKGROUND Various types of metal objects (e.g., machinery parts) are electroplated in electroplating solution baths or chambers. A layer of coating applied on a metal object via electroplating may provide a protective barrier that improves, for example, the corrosion resistance, strength, and durability of the metal object. However, electroplated metal objects may become susceptible to damage during assembly, handling, and/or use. Such damage may result in one more cracks (or fissure or chips) in the coating, which may lead to corrosion or rusting on the surfaces of the metal objects at or near the locations of the cracks. As such, there is a need for an efficient and cost effective solution to producing improved corrosion resistant electroplated structures.
The present disclosure is directed to overcoming one or more of these challenges. The background description provided herein is for the purpose of generally presenting the context of the disclosure. Unless otherwise indicated herein, the materials described in this section are not prior art to the claims in this application and are not admitted to be prior art, or suggestions of the prior art, by inclusion in this section.
SUMMARY OF THE DISCLOSURE According to certain aspects of the disclosure, an electroplate laminated structure and methods of fabricating the same for improving corrosion resistance of electroplated structures are provided in this disclosure.
In one embodiment, a method of fabricating a laminated structure is disclosed. The method may comprise: providing an object in an electroplating solution; forming a first layer on the object by applying a first electric current, the first electric current being associated with a first current density; and forming a second layer on the first layer by applying a second electric current, the second electric current being associated with a second current density. Each of the first layer and the second layer may include, at least in part, phosphorus, and the first current density and the second current density may be different.
In another embodiment, a corrosion-resistant laminated structure is disclosed. The corrosion-resistant laminated structure may comprise an object and a first layer may be formed on the object. The first layer may have a first thickness. The corrosion-resistant laminated structure may also comprise a second layer formed on the first layer. The second layer may have a second thickness. The first layer and the second layer may be formed by applying a first electric current and a second electric current, respectively, to the object placed in an electroplating solution. A first current density associated with the first electric current may be different from a second current density associated the second electric current. Each of the first layer and the second layer may include, at least in part, phosphorus.
In another embodiment, a method of fabricating a laminated structure is disclosed. The method may comprise: providing an object in an electroplating solution; forming a first layer on the object by applying a first electric current having a first current density; forming a second layer on the first layer by applying a second electric current having a second current density; and forming a third layer on the second layer by applying a second electric current having the first current density. Each of the first layer, the second layer, and the third layer includes, at least in part, phosphorus.
Additional objects and advantages of the disclosed embodiments will be set forth in part in the description that follows, and in part will be apparent from the description, or may be learned by practice of the disclosed embodiments. The objects and advantages of the disclosed embodiments will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. As will be apparent from the embodiments below, an advantage to the disclosed structures and methods is that structures laminated with alternating hard and soft electroplate layers improve the wear and corrosion resistance of the electroplate laminated structures.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosed embodiments, as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate various exemplary embodiments and together with the description, serve to explain the principles of the disclosed embodiments.
FIG. 1 depicts an example electroplating system, according to one or more aspect of the present disclosure.
FIGS. 2A and 2B illustrate an impact of a damaged electroplate coating on the corrosion resistance of an electroplated structure, according to one or more aspects of the present disclosure.
FIGS. 3A and 3B depict a set of example electroplate laminated structures, according to one or more aspect of the present disclosure.
FIGS. 4A and 4B depict another set of example electroplate laminated structures, according to one or more aspects of the present disclosure.
FIGS. 5A and 5B depict yet another set of example electroplate laminated structure, according to one or more aspects of the present disclosure.
FIG. 6 depicts a corrosion-resistant property of an example electroplate laminated structure, according to one or more aspects of the present disclosure.
FIG. 7 depicts a flowchart of an example method for fabricating an electroplate laminated structure, according to one or more aspects of the present disclosure.
DETAILED DESCRIPTION OF EMBODIMENTS The following embodiments describe electroplate laminated structures and methods of fabricating electroplate laminated structures.
As described above, there is a need in the electroplating field and other related industries including, but not limited to, the oil and gas industries, to prevent corrosion and rusting of metal objects. For example, large machinery parts (e.g., mud motor rotor) used in the oil and gas industries are typically coated with hard, wear and corrosion resistant electroplating coatings, for example, for strength, protection, and/or durability. However, such hard, wear and corrosion resistant coatings are susceptible to cracking during manufacturing, handling, and/or operation. As such, the base metal of electroplated machinery parts may corrode or rust at or near the locations of the cracks. Further, corrosion may undercut the bonding between the electroplate coatings and the base metal of the electroplated machinery parts, which may separate the electroplate coatings from the base metal and render the machinery parts ineffective or inoperable.
Accordingly, the following embodiments describe systems and methods for fabricating electroplate laminated structures having alternating hard and soft electroplate layers that improve the wear and corrosion resistance of the electroplate laminated structures. According to certain aspects of the present disclosure, an object (e.g., a metallic machinery part) may be provided in an electroplating solution. A first layer of electroplating material may be formed on the object by applying a first electric current. The first electric current may be associated with a first current density. Further, a second layer of electroplating material may be formed on the first layer by applying a second electric current. The second electric current may be associated with a second current density. In one embodiment, the first current density and the second current density may be different. Each of the first layer and the second layer may include, at least in part, phosphorus. The amount of phosphorus content in the first layer may be lower or greater than the amount of phosphorus content in the second layer. In one embodiment, a plurality of layers with varying amounts of phosphorous content may be formed by controlling the density of the current being applied. The amount of phosphorus content in the first layer and the second layer may determine the hardness or ductility of the layers. For example, a first layer having a relatively low amount of phosphorus content may form a relatively soft layer on the object, and a second layer having a relatively high amount of phosphorous content may form a relatively hard layer on the first layer. Providing alternating, relatively soft and hard layers of electroplate coatings on an object may terminate cracks at one or more soft layers or may direct cracks to propagate laterally instead of downward toward the object. Accordingly, the electroplate laminated structures of the present disclosure may significantly reduce or prevent the above-described corrosion or rusting on objects formed of metal (e.g., three times or more compared to a hard, single electroplate layer structure) by providing alternating layers of soft and hard electroplate coatings with varying amounts of phosphorous content.
The subject matter of the present description will now be described more fully hereinafter with reference to the accompanying drawings, which form a part thereof, and which show, by way of illustration, specific exemplary embodiments. An embodiment or implementation described herein as “exemplary” is not to be construed as preferred or advantageous, for example, over other embodiments or implementations; rather, it is intended to reflect or indicate that the embodiment(s) is/are “example” embodiment(s). Subject matter can be embodied in a variety of different forms and, therefore, covered or claimed subject matter is intended to be construed as not being limited to any exemplary embodiments set forth herein; exemplary embodiments are provided merely to be illustrative. Likewise, a reasonably broad scope for claimed or covered subject matter is intended. Among other things, for example, subject matter may be embodied as methods, devices, components, or systems. Accordingly, embodiments may, for example, take the form of hardware, software, firmware, or any combination thereof (other than software per se). The following detailed description is, therefore, not intended to be taken in a limiting sense.
Throughout the specification and claims, terms may have nuanced meanings suggested or implied in context beyond an explicitly stated meaning. Likewise, the phrase “in one embodiment” as used herein does not necessarily refer to the same embodiment and the phrase “in another embodiment” as used herein does not necessarily refer to a different embodiment. It is intended, for example, that claimed subject matter include combinations of exemplary embodiments in whole or in part.
The terminology used below may be interpreted in its broadest reasonable manner, even though it is being used in conjunction with a detailed description of certain specific examples of the present disclosure. Indeed, certain terms may even be emphasized below; however, any terminology intended to be interpreted in any restricted manner will be overtly and specifically defined as such in this Detailed Description section. Both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the features, as claimed.
In this disclosure, the term “based on” means “based at least in part on.” The singular forms “a,” “an,” and “the” include plural referents unless the context dictates otherwise. The term “exemplary” is used in the sense of “example” rather than “ideal.” The term “or” is meant to be inclusive and means either, any, several, or all of the listed items. The terms “comprises,” “comprising,” “includes,” “including,” or other variations thereof, are intended to cover a non-exclusive inclusion such that a process, method, or product that comprises a list of elements does not necessarily include only those elements, but may include other elements not expressly listed or inherent to such a process, method, article, or apparatus. Relative terms, such as, “substantially” and “generally,” are used to indicate a possible variation of ±10% of a stated or understood value.
Referring now to the appended drawings, FIG. 1 shows an overview of an example electroplating system 100, according to one or more aspects of the present disclosure. In one embodiment, the system 100 may include an electroplating bath (or tank or container) 102, a controller system 103, a variable power supply 104, one or more cathodes (or cathode electrodes) 106, one or more anodes (or anode electrodes) 108, and a pump 112. In one embodiment, the electroplating bath 102 may be configured to receive and contain one or more electroplating solutions 114. For example, an electroplating solution 114 may include water, a hydrochloric acid (HCl) solution, a nickel (Ni) solution, a cobalt (Co) solution, a phosphorous (P) solution, a cobalt phosphorous (Co—P) solution, etc. Further, the electroplating bath 102 may be configured to receive and contain one or more parts or work pieces 110 (e.g., a shaft, rod, beam, cylinder, bar, etc.) to be electroplated. The size of the electroplating bath 102 may be designed to be any size suitable for electroplating various parts and work pieces.
Still referring to FIG. 1, the one or more cathodes 106 and anodes 108 may be coupled to or placed in the electroplating bath 102. In one embodiment, the one or more cathodes 106 and anodes 108 may be arranged in the electroplating bath 102, so as to be in contact, fully or partially, with the electroplating solution 114. The one or more cathodes 106 and anodes 108 may provide various levels of electric current necessary to facilitate electroplating the one or more parts 110.
Still referring to FIG. 1, the controller system 103 may include one or more timers, switches, sensors, controllers, etc. (not shown in the figure for brevity and clarity) and may facilitate the automatic or manual electroplating process of the present disclosure. For example, the controller system 103 may be configured to control the variable power supply 104 to apply electric current to the electroplating bath 102 via the one or more cathodes 106 and anodes 108. The variable power supply 104 may include one or more rectifiers and may act as a current source. Upon receiving a command or a signal from the controller system 103, the variable power supply 104 may provide electric current via the one or more cathodes 106 and anodes 108. The electric current may initiate a chemical reaction between the electroplating solution 114 and the one or more parts 110 in the electroplating bath 102. The electric current provided to the electroplating bath 102 may be controlled by the one or more rectifiers. In some embodiments, the system 100 may be completely automated via the controller system 103, by automatically monitoring various timers and/or sensors coupled to the system 100. The manner in which various components are arranged in FIG. 1 is merely exemplary. In practice, there may be additional components, fewer components, different components, or differently arranged components than those shown in FIG. 1.
FIGS. 2A and 2B depict an example electroplated structure 210, according to one or more aspects of the present disclosure. In particular, FIG. 2A illustrates an impact of a damaged electroplate coating (e.g., a crack or crevice) on the corrosion resistance of the structure 210. The structure 210 may comprise a metal object, for example, one or more parts or work pieces (e.g., one or more parts 110) of a device, a tool, equipment, a machine, etc. In one embodiment, the structure 210 may comprise a base metal layer 212 (i.e., a substrate 212) and a coating layer 214. The base metal layer 212 may be an outermost layer of a metal object (e.g., one or more parts 110). The coating layer 214 may be formed on an outer surface of the base metal layer 212 in accordance with an electroplating process of the present disclosure. For example, the metal object having the base metal layer 212 may be electrically coupled to the cathode 106. The metal object may then be completely or partially immersed in the electroplating solution 114 of the electroplating bath 102. The variable power supply 104 may apply electric current to the base metal layer 212 via the cathode 106 and the anode 108 for a predetermined period of time. The application of electric current may facilitate a chemical reaction between the electroplating solution 114 and the base metal layer 212, forming the coating layer 214. In one embodiment, the controller system 103 may control the pump 112 to agitate the electroplating solution 114 and keep electroplating particles in suspension in order to remove materials from the outer surface of the base metal layer 212 for efficient electroplating and prevention of impurity build-up.
Still referring to FIG. 2A, the thickness (or amount) of the coating layer 214 applied to the base metal layer 212 may be determined based on various electroplating conditions and factors, such as, for example, a current density, a current application duration, an agitation rate, cathode 106 and anode 108 spacing, etc. Further, the coating layer 214 may include an alloy (e.g., nickel phosphorus alloy, cobalt phosphorous alloy, etc.) with varying element compositions. In one embodiment, the coating layer 214 may be hardened (e.g., precipitation hardening) by undergoing one or more heat treatments. The hardness of a coating layer may vary based on the composition of the coating layer. For example, the hardness of a coating layer (e.g., cobalt phosphorous alloy) comprising, for example, 7-8% phosphorous content may increase by about 400 Vickers Pyramid Number (HV). That is, the hardness may increase from about 600 HV to about 1000 HV after going through a precipitation hardening heat treatment step. Alternatively, the hardness of a coating layer (e.g., cobalt phosphorous alloy) comprising, for example, below 6% phosphorous content, may increase by only about 100 HV. As described above, although hard, wear-resistant coatings may provide a stronger outer layer, they may become susceptible to cracking during assembly, manufacturing, handling, and/or operation. In the example of FIGS. 2A and 2B, the coating layer 214 has a relatively high level of hardness (e.g., greater than about 1000 HV) and may be more susceptible to cracks 216 than a coating layer with a relatively lower level of hardness (e.g., about 800 HV). Further, the cracks 216 on the hard coating layer 214 may cause corrosion or rust on the base metal layer 212, as further described in FIG. 2B.
During usage of the structure 210, debris, liquid, or chemicals (e.g., chloride solution) that induce corrosion or rusting may enter into the cracks 216. As shown in FIG. 2B, corrosion or rusting may occur at locations 228 where the cracks 216 may propagate or grow all the way down to the base metal layer 212. The corrosion or rusting at the locations 228 may damage the structure 210 and/or undercut between the coating layer 214 and the base metal layer 212, which may separate the coating layer 214 from the base metal layer 212, rendering the structure 210 unusable or inoperable.
FIG. 3A depicts an example electroplate laminated structure 310 that reduces or prevents corrosion or rusting caused by cracks, according to one or more aspects of the present disclosure. The structure 310 may comprise a metal object, for example, one or more parts or work pieces (e.g., one or more parts 110) of a device, a tool, equipment, a machine, etc. In one embodiment, the structure 310 may comprise a base metal layer 312, a first coating layer 314, and a second coating layer 316. The base metal layer 312 may be an outermost layer of a metal object (e.g., one or more parts 110). The first coating layer 314 may be formed on an exposed surface of the base metal layer 312, in accordance with an electroplating process of the present disclosure. For example, the metal object having the base metal layer 312 may be physically and electrically coupled to the cathode 106. The metal object may then be completely or partially immersed in the electroplating solution 114 of the electroplating bath 102. The controller system 103, by way of the variable power supply 104, may apply a first electric current having a first current density (e.g., 125 amps per foot squared (ASF)) to the base metal layer 312 via the cathode 106 and the anode 108 for a first predetermined period of time. The application of the first electric current may facilitate a chemical reaction between the electroplating solution 114 and the base metal layer 312, forming the first coating layer 314. Upon forming the first coating layer 314, the variable power supply may 104 apply a second electric current having a second current density (e.g., 25 ASF) to the first coating layer 314 for a second predetermined period of time. The application of the second electric current may facilitate a chemical reaction between the electroplating solution 114 and the first coating layer 314, forming the second coating layer 316. The process of forming the first coating layer 314 and the second coating layer 316 may be repeated so as to form multiple alternating electroplate coating layers as shown in FIG. 3A. In the example shown in FIG. 3A, the structure 310 includes twelve coating layers. However, it should be noted that any number of alternating coating layers may be formed using the electroplating method of the present disclosure. In one embodiment, the pump 112 may agitate the electroplating solution 114 and keep electroplating particles in suspension in order to remove materials from the outer surface of the base metal layer 312 for efficient electroplating and prevention of impurity build-up.
Still referring to FIG. 3A, the thicknesses (or amount) and/or hardness of the first and second coating layers 314, 316 may be configured based on various electroplating conditions and factors, such as, for example, a current density, a current application duration, an agitation rate, cathode 106 and anode 108 spacing, etc. Further, the first and second coating layers 314, 316 may each include an alloy (e.g., nickel phosphorus alloy, cobalt phosphorous alloy, etc.) with varying element compositions. In one embodiment, the first coating layer 314 and the second coating layer 316 may be hardened (e.g., precipitation hardening) by undergoing one or more heat treatments. The hardness of the first coating layer 314 and the second coating layer 316 may vary based at least on the composition of the first coating layer 314 and the second coating layer 316, as described above in reference to FIGS. 2A and 2B.
In one embodiment, the first coating layer 314 may comprise a hardness level that is different from the hardness level of the second coating layer 316. For example, the first coating layer 314 may comprise a relatively softer layer than the second coating layer 316. In one embodiment, the first coating layer 314 may have, for example, a hardness level of about 800 HV, and the second coating layer 316 may have, for example, a hardness level of about 1000 HV. Of course, the specific levels of hardness of the first and second coating layers 314, 316 may be varied depending on the use case. In one embodiment, the hardness levels of the first coating layer 314 and the second coating layer 316 may be controlled based at least on the amount of phosphorous content. Thus, a first coating layer 314 (e.g., cobalt phosphorous alloy) comprising, for example, about 6% phosphorous content or less may yield a hardness level that is lower than a second coating layer 316 comprising, for example, about 7-8% phosphorous content. As described above, in accordance with FIGS. 2A and 2B, the hardness of a coating layer (e.g., cobalt phosphorous alloy) comprising, for example, 7-8% phosphorous content may increase by about 400 Vickers Pyramid Number (HV). That is, the hardness may increase from about 600 HV to about 1000 HV after going through a precipitation hardening heat treatment step. Alternatively, the hardness of a coating layer (e.g., cobalt phosphorous alloy) comprising, for example, about 6% phosphorous content or less, may increase by only about 100 HV.
Still referring to FIG. 3A, the structure 310 may significantly reduce or prevent the above-described corrosion or rusting by forming alternating layers of coating with varying phosphorous content amounts (e.g., phosphorous content ratios). That is, the first coating layer 314 with a relatively low phosphorous content (e.g., under 6%) may be formed on the base metal layer 312. Subsequently, the second coating layer 316 with a higher phosphorous content (e.g., equal to or greater than 7%) than the first coating layer 314 may be formed. A relatively soft (e.g., about 800 HV) electroplating layer (e.g., first coating layer 314) may have greater ductility or pliability compared to a relatively hard (e.g., 1000 HV) electroplating layer (e.g., second coating layer 316). As such, providing alternating layers of soft and hard coatings on a base metal layer may terminate cracks at or near a soft coating layer, or may direct cracks to propagate laterally instead of downward (later shown in detail in FIG. 6). The ratio of phosphorous content between the first coating layer 314 and the second coating layer 316, the thickness of the coating layers, and/or the number of electroplate coating layers (e.g., first and second coating layers 314, 316) may affect the efficacy of the structure 310 in preventing corrosion or rusting. As such, the phosphorous content ratio, thickness, and/or number of the electroplate coating layers may be adjusted depending on the use case.
Still referring to FIG. 3A, the ratio of phosphorous content between the first coating layer 314 and the second coating layer 316 may be adjusted by controlling the current density of the electric current applied during the electroplating process of the present disclosure. In one embodiment, the current density and the current application duration may be controlled by the controller system 103 by way of the variable power supply 104 either automatically or manually by an operator. The controller system 103 may program the variable power supply 104 to control the rectifier of the variable power supply 104 to apply electric current at different densities during different time periods. Additionally or alternatively, the current density and the current application duration may be controlled by the variable power supply 104 by manually programming the variable power supply 104 and/or by manually changing the output of current at different time periods by an operator. In this exemplary embodiment, the ratio of the amount of phosphorous content between the first coating layer 314 and the second coating layer 316 may be 1 to 2. As such, the structure 310 of FIG. 3A may comprise alternating soft and hard coating layers, with the ratio of the amount of phosphorous content therebetween being 1 to 2. Further, the total thickness of the coating layers of the structure 310 may be about 10 millimeters. Of course, the ratio of phosphorous content, the thickness of each layer or the total thickness of all layers combined, and/or the number of coating layers may be varied or adjusted depending on the use case.
FIG. 3B depicts another example electroplate laminated structure 320 that reduces or prevents corrosion or rusting caused by cracks, according to one or more aspects of the present disclosure. The structure 320 may comprise a metal object, for example, one or more parts or work pieces (e.g., one or more parts 110) of a device, a tool, equipment, a machine, etc. In one embodiment, the structure 320 may comprise a base metal layer 322, a first coating layer 324, and a second coating layer 326. The base metal layer 322 may be an outermost layer of a metal object (e.g., one or more parts 110). The first coating layer 324 and the second coating layer 326 may be formed in the similar manner as described in reference to FIG. 3A above. In the example of FIG. 3B, the first coating layer 324 and the second coating layer 326 may comprise a different thickness (e.g., smaller thickness) than the thickness of the first coating layer 314 and the second coating layer 316 of FIG. 3A. The thickness of each coating layer (first coating layer 324 or second coating layer 326) may be configured based on the current density and/or the duration of current application during the electroplating process of the present disclosure. For example, applying about 125 ASF of electric current for about 0.167 hour (approximately 10 minutes) may yield about 0.5 millimeters of thickness. Alternatively, applying about 50 ASF of electric current for about 1 hour may yield about 2 millimeters of thickness. Of course, the thickness may vary based on other factors, such as, an agitation rate, cathode 106 and anode 108 spacing, etc. Thus, based on the characteristic and/or use of the structure 320, electroplate coating layers having different thicknesses may be formed in accordance with the present disclosure. In the embodiment of FIG. 3B, the first coating layer 324 and the second coating layer 326 may comprise the same thickness. However, the first coating layer 314 may comprise a higher phosphorous content than the second coating layer 326. As such, the first coating layer 324 may be relatively softer than the second coating layer 326. Accordingly, the hardness as well as the thickness of electroplating coating layers (e.g., first coating layer 324 and/or second coating layer 326) may be determined depending on the use case, the structure 320 having desired hardness and thickness may be formed by configuring various parameters associated with those properties (e.g., current density, current application duration, agitation rate, cathode 106 and anode 108 spacing, etc.).
FIG. 4A depicts yet another example electroplate laminated structure 410 that reduces or prevents corrosion or rusting caused by cracks, according to one or more aspects of the present disclosure. The structure 410 may comprise a metal object, for example, one or more parts or work pieces (e.g., one or more parts 110) of a device, a tool, equipment, a machine, etc. In one embodiment, the structure 410 may comprise a base metal layer 412, a first coating layer 414, a second coating layer 416, and a third coating layer 418. The first coating layer 414, the second coating layer 416, and the third coating layer 418 may be formed in the similar manner as described in reference to FIGS. 3A-3B above. In the example of FIG. 4A, the first coating layer 414 may comprise a first thickness, the second coating layer 416 may comprise a second thickness, and the third coating layer 418 may comprise a third thickness. The thickness of each layer may be controlled using the electroplating process described in FIG. 3B above.
Still referring to FIG. 4A, the first thickness of the first coating layer 414 may be greater than the thickness of the second coating layer 416 and the third coating layer 418. Further, the first coating layer 414 and the third coating layer 418 may comprise relatively soft layers compared to the second coating layer 416. In some embodiments, electroplate laminated structure with a relatively thick soft layer may yield an improved corrosion or rust resistance because cracks tend to terminate at a relatively soft layer. Thus, forming a relatively thicker soft layer as the first coating layer as shown in FIG. 4A may improve the prevention of cracks propagating through to the base metal layer 412 of the structure 410.
FIG. 4B depicts yet another example electroplate laminated structure 420 that reduces or prevents corrosion or rusting caused by cracks, according to one or more aspects of the present disclosure. The structure 420 may comprise a metal object, for example, one or more parts or work pieces (e.g., one or more parts 110) of a device, a tool, equipment, a machine, etc. In one embodiment, the structure 420 may comprise a base metal layer 422, a first coating layer 424, a second coating layer 426, and a third coating layer 428. The first coating layer 424, the second coating layer 426, and the third coating layer 428 may be formed in the similar manner as described in reference to FIGS. 3A-3B above. In this exemplary embodiment, the first coating layer 424 may comprise a first thickness, the second coating layer 426 may comprise a second thickness, and the third coating layer 428 may comprise a third thickness. Notably, FIG. 4B illustrates an example of varying the thicknesses of the electroplate coating layers. For example, the thickness of the second coating layer 426 and the third coating layer 428 may be equal or substantially similar, while the thickness of each of the second coating layer 426 and the third coating layer 428 may be smaller than the thickness of the first coating layer 424. Further, the thickness of the second and third coating layers 426, 428 may be smaller than the thickness of the second and third coating layers 416, 418 illustrated in FIG. 4A. The thickness of the electroplate coating layers of the structure 420 may be controlled similarly in the manner described in reference to FIG. 3B. As such, the exemplary embodiment of FIG. 4B may include a relatively thick soft first coating layer 424, similar to the first coating layer 414 in FIG. 4A, the second and third coating layers 426, 428 being substantially thinner than the first coating layer 424. In some embodiments, as described above, an electroplate laminated structure with a relatively thick soft layer may yield an improved corrosion or rust resistance because cracks tend to terminate at a relatively soft layer. Thus, forming a relatively thicker soft layer as the first coating layer as shown in FIG. 4B may improve the prevention of cracks propagating through to the base metal layer 422 of the structure 420.
FIG. 5A depicts yet another example electroplate laminated structure 510 that reduces or prevents corrosion or rusting caused by cracks, according to one or more aspects of the present disclosure. The structure 510 may comprise a metal object, for example, one or more parts or work pieces (e.g., one or more parts 110) of a device, a tool, equipment, a machine, etc. In one embodiment, the structure 510 may comprise a base metal layer 512, a first coating layer 514, and a second coating layer 516. The first coating layer 514 and the second coating layer 516 may be formed in the similar manner as described in reference to FIGS. 3A-3B and FIGS. 4A-4B above. In this exemplary embodiment, the first coating layer 514 may comprise a first thickness and the second coating layer 516 may comprise a second thickness. The first thickness of the first coating layer 514 may be greater than the second thickness of the second layer 516. For example, the ratio of thickness between the first coating layer 514 and the second layer 516 may be 1 to 2. Of course, the thickness ratio between the first and second coating layers 514, 516 may be varied based on the design and/or use of the structure 510. In one embodiment, the first coating layer 514 may comprise a relatively soft layer compared to the second coating layer 516. As such, providing alternating layers of relatively soft and hard coatings on a base metal layer may terminate cracks or may direct cracks to propagate laterally instead of downward (later shown in detail in FIG. 6). As described above, an electroplate laminated structure with a relatively thick soft layer may yield an improved corrosion or rust resistance because cracks tend to terminate at the relatively soft layer. Thus, laminating one or more relatively soft electroplate coating layers with one or more relatively hard electroplate coating layers in an alternating manner may improve the prevention of cracks propagating through to the base metal layer 514 of the structure 510.
FIG. 5B depicts yet another example electroplate laminated structure 520 that reduces or prevents corrosion or rusting caused by cracks, according to one or more aspects of the present disclosure. The structure 520 may comprise a metal object, for example, one or more parts or work pieces (e.g., one or more parts 110) of a device, a tool, equipment, a machine, etc. In one embodiment, the structure 520 may comprise a base metal layer 522, a first coating layer 524, a second coating layer 526, and a third coating layer 528. The first coating layer 524, the second coating layer 526, and the third coating layer 528 may be formed in the similar manner as described in reference to FIGS. 3A-3B, 4A-4B, and 5A above. In the example of FIG. 5B, the first coating layer 524 may comprise a first thickness, the second coating layer 526 may comprise a second thickness, and the third coating layer 528 may comprise a third thickness. FIG. 5B illustrates an example of forming the first coating layer 524 as the thickest layer compared to the second coating layer 526 and the third coating layer 528. After forming the first coating layer 524, multiple hard and soft coating layers may be formed in an alternating manner, similar to the structure 510 in FIG. 5A. For example, the ratio of thickness between the second coating layer 526 and the third layer 528 may be 1 to 2. Of course, the thickness ratio between the second and third coating layers 526, 528 may be varied based on the design and/or use of the structure 520. The thickness of the electroplate coating layers of the structure 520 may be controlled similarly in the manner described in reference FIG. 3B. As such, the exemplary embodiment of FIG. 5B may include the relatively thick soft first coating layer 524, and the second and third coating layers 526, 528 that are thinner than the first coating layer 524. In some embodiments, as described above, an electroplate laminated structure with a relatively thick soft layer may yield an improved corrosion or rust resistance because cracks tend to terminate at the relatively soft layer. Thus, laminating one or more relatively soft electroplate coating layers with one or more relatively hard electroplate coating layers in an alternating manner may improve the prevention of cracks propagating through to the base metal layer 524 of the structure 520.
One skilled in the art will recognize that the scope of the present disclosure is not limited to the specific embodiments illustrated in FIGS. 3A-3B, 4A-4B, and 5A-5B. Rather, FIGS. 3A-3B, 4A-4B, and 5A-5B illustrate structures with varying dimensions and specifications, in order to suggest that the number of alternating relatively soft and hard layers, thickness of the layers, hardness of the layers, and the manner by which soft and hard layers are arranged (e.g., alternating or non-alternating, i.e., random) may all be configured in various ways using the parameters discussed above, such as the electroplating current density, current application duration, agitation rate, cathode and anode spacing, etc.
FIG. 6 illustrates a corrosion-resistant property of an example electroplate laminated structure, in accordance with one or more aspects of the present disclosure. The structure 610 may comprise a metal object, for example, one or more parts or work pieces (e.g., one or more parts 110) of a device, a tool, equipment, a machine, etc. In one embodiment, the structure 610 may comprise a base metal layer 612, a first coating layer 614 and a second coating layer 616. The first coating layer 614 and the second coating layer 616 may be formed in the similar manner as described in reference to FIGS. 3A-3B, 4A-4B, and 5A-5B above. As discussed above, providing alternating, relatively soft and hard layers of electroplate coatings on a base metal layer may terminate cracks or may direct cracks to propagate laterally instead of downward. FIG. 6 shows cracks 618 propagating from the outermost layer of the structure 610. By alternating soft and hard layers, the propagation of the cracks 618 starting from a hard, outer layer may be mitigated when the crack 618 reaches a soft layer. In some embodiments, the soft layer may cause the cracks 618 to travel relatively laterally across the soft layer rather than propagating downward toward the base metal layer 612. As such, laminating soft and hard coating layers in an alternating manner as shown FIGS. 3A-3B, 4A-4B, 5A-5B, and 6 may improve the efficacy of preventing cracks from propagating through to the base metal layer of the electroplate laminated structures of the present disclosure.
FIG. 7 depicts a flowchart of an exemplary method 700 for fabricating an electroplate laminated structure (e.g., structure 310, 320, 410, 420, 510, 520, and/or 600), in accordance with one or more aspects of the present disclosure. At step 702, an object (e.g., one or more parts 110) may be provided (or immersed) in an electroplating solution (e.g., electroplating solution 114). In one embodiment, the electroplating solution may be agitated by the pump 112 for a predetermined period of time. At step 704, a first layer (e.g., first coating layer 314, 324, 414, 424, 514, 524, or 614) may be formed on the object by applying a first electric current by the controller system 103 or the variable power supply 104. The first electric current may be associated with a first current density. At step 706, a second layer (e.g., second coating layer 316, 326, 416, 426, 516, 526, or 616) may be formed on the first layer by applying a second electric current using the controller system 103 or the variable power supply 104. The second electric current may be associated with a second current density. The first current density and the second current density may be the same or different. In one embodiment, the first electric current may be applied for a first duration, and the second electric current may be applied for a second duration. The first duration and the second duration may be the same or different. In one embodiment, steps 704 and 706 may be performed iteratively in order to form multiple first layers and multiple second layers, each of the multiple second layers formed on a corresponding one of the multiple first layers, thereby forming alternating sets of first and second layers as depicted in FIGS. 3A-3B, 4A-4B, 5A-5B, and 6 for example.
In some embodiments, a third layer may be formed on the second layer by applying a third electric current. The third electric current may be associated with a third current density. The third current density and the first current density may be the same or different. The third electric current may be applied for a duration that is the same as or different from the first duration. Furthermore, during or after the electroplating process, heat may be applied to the laminated structured for a predetermined amount of time.
In one embodiment, the first current density and the second current density may be different. In one embodiment, the first current density may be lower than the second current density. Further, each of the first layer and the second layer may include, at least in part, phosphorus. In one embodiment, the amount of phosphorous in the first layer may be greater than the second layer. In some embodiments, the first layer may comprise a first thickness and the second layer comprises a second thickness. In another embodiment, the first thickness may be greater than the second thickness. In yet another embodiment, the first thickness may be equal or substantially similar to the second thickness.
It should be appreciated that in the above description of exemplary embodiments, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed embodiment requires more features than are expressly recited in each claim. Thus, the claims following the Detailed Description are hereby expressly incorporated into this Detailed Description, with each claim standing on its own as a separate embodiment of this disclosure.
Furthermore, while some embodiments described herein include some but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the disclosure, and form different embodiments, as would be understood by those skilled in the art. For example, in the following claims, any of the claimed embodiments can be used in any combination.
Thus, while certain embodiments have been described, those skilled in the art will recognize that other and further modifications may be made thereto without departing from the spirit of the disclosure, and it is intended to claim all such changes and modifications as falling within the scope of the disclosure. For example, functionality may be added or deleted from the block diagrams and operations may be interchanged among functional blocks. Steps may be added or deleted to methods described within the scope of the present disclosure.
The above disclosed subject matter is to be considered illustrative, and not restrictive, and the appended claims are intended to cover all such modifications, enhancements, and other implementations, which fall within the true spirit and scope of the present disclosure. Thus, to the maximum extent allowed by law, the scope of the present disclosure is to be determined by the broadest permissible interpretation of the following claims and their equivalents, and shall not be restricted or limited by the foregoing detailed description. While various implementations of the disclosure have been described, it will be apparent to those of ordinary skill in the art that many more implementations and implementations are possible within the scope of the disclosure. Accordingly, the disclosure is not to be restricted.
