Nickel-boron coating for housings and casings

Abstract

Embodiments of the present disclosure generally relate to enclosures and casings for electronic devices and memory devices, and more particularly to such enclosures and casings having a nickel-boron coating and methods for forming such a nickel-boron coating. In one embodiment, an article for housing at least a portion of an electronic device is provided, the article comprising a metal-containing substrate and a layer comprising nickel and boron disposed on at least a portion of the metal-containing substrate, wherein: the amount of nickel in the layer is about 95 wt% or greater based on the total amount of nickel and boron in the layer, and the amount of boron in the layer is about 5 wt% or less. The article has a thermal conductivity of about 25 W / mK or greater, a scratch hardness of about 0.5 GPa or greater, a coefficient of friction of about 0.4 or less, or a combination thereof.

Description

Background Technology Technical Field

[0001] The embodiments of this disclosure generally relate to housings and enclosures for electronic devices and memory devices, and more specifically to such housings and enclosures having a nickel-boron coating and methods for forming such nickel-boron coatings.

[0002] Description of related fields

[0003] Polymers and resins such as epoxy resins, paints, and acrylic resins are commonly used to coat the metal casings and housings of solid-state drive (SSD) products, hard disk drive (HDD) products, heat sink products, and retail packaging (RPG) products such as USB connectors. However, the soft nature, viscoelastic behavior, and low thermal conductivity of such polymer-based materials affect their practical value. For example, when drives have housings coated with conventional polymers, the typical contact between the thermal interface material and the housing coating is not effective in dissipating the drive's heat. The soft nature of conventional coatings also makes the coatings and housings susceptible to scratches and abrasion. Furthermore, due to oil seepage on the housing surface, coupled with the housing's low scratch and abrasion resistance, rejection rates for SSD, HDD, and RPG packaging and housings can be as high as 10% or more in some cases.

[0004] Currently, solutions to these problems are very limited for products unrelated to the electronics industry, let alone SSDs, HDDs, RPGs, other memory devices, and electronic devices. For example, nickel-boron (NiB) coatings have been used in saws, piston rings, and bearings, or other structures subjected to cutting and friction, to mitigate scratches or improve corrosion resistance, but they have not been used as scratch-resistant coatings for housing and packaging applications where surface properties may be critical in determining product rejection. Furthermore, such NiB coatings often contain additional materials, such as stabilizers or metals like thallium or gold, making them unusable, atomically inefficient, and / or amorphous. Additionally, conventional NiB coating techniques typically involve alkaline deposition baths with borohydride reducing agents and require heat treatment to achieve corrosion resistance and hardness. These alkaline baths and borohydride reagents are incompatible with typical housings and substrates for electronic and memory devices, and the heat treatment process is an additional operation that reduces production volume and increases manufacturing costs.

[0005] There is a need for new and improved nickel-boron coatings for housings and enclosures of, for example, electronic devices and memory devices, to overcome one or more of the deficiencies in the art. Summary of the Invention

[0006] The embodiments of this disclosure generally relate to housings and enclosures for electronic devices and memory devices, and more specifically to such housings and enclosures having a nickel-boron coating and methods for forming such nickel-boron coatings.

[0007] In one embodiment, an article of manufacture for accommodating at least a portion of an electronic device is provided. The article of manufacture includes a metal substrate and a layer comprising nickel and boron, the layer being disposed on at least a portion of the metal substrate, wherein: based on the total amount of nickel and boron in the layer, the amount of nickel in the layer is about 95% by weight or greater, and the total amount of nickel and boron in the layer does not exceed 100% by weight; and based on the total amount of nickel and boron in the layer, the amount of boron in the layer is about 5% by weight or less. The article of manufacture has a thermal conductivity of about 25 W / mK or greater (ISO 22007-2), a scratch hardness of about 0.5 GPa or greater (ISO 4586-2), a coefficient of friction of about 0.4 or less (ASTM G133), or a combination thereof.

[0008] In another embodiment, an article of manufacture is provided. The article of manufacture includes an electronic device and a coated substrate disposed on at least a portion of the electronic device. The coated substrate includes a metal-containing substrate and a coating disposed on at least a portion of the metal-containing substrate. The coating has a thickness of about 15 μm or less. The coating contains about 95% by weight or more of nickel based on the total amount of nickel and boron in the coating, and about 5% by weight or less of boron based on the total amount of nickel and boron in the coating, wherein the total amount of nickel and boron in the coating does not exceed 100% by weight. The coated substrate has a thermal conductivity of about 25 W / mK or greater (ISO 22007-2), a scratch hardness of about 0.5 GPa or greater (ISO 4586-2), a coefficient of friction of about 0.4 or less (ASTM G133), or a combination thereof.

[0009] In another embodiment, a method for manufacturing a housing or enclosure for an electronic device is provided. The method includes forming a layer comprising nickel and boron on a substrate by electroless deposition in a deposition bath, wherein the deposition bath is formed from a nickel source, a boron source, and a complexing agent, wherein the amount of nickel in the layer is about 95% by weight or greater, and the amount of boron in the layer is about 5% by weight or less, based on the total amount of nickel and boron in the layer. Attached Figure Description

[0010] Therefore, a detailed understanding of the foregoing features of this disclosure, a more specific description of this disclosure, and the foregoing brief overview can be obtained by referring to the embodiments, some of which are shown in the accompanying drawings. However, it should be noted that the drawings only illustrate typical embodiments of this disclosure and should therefore not be considered as limiting its scope, as this disclosure allows for other equally effective embodiments.

[0011] Figure 1A It is a cross-section of an exemplary article of at least one embodiment of the present disclosure.

[0012] Figure 1B It is a cross-section of an exemplary article of at least one embodiment of the present disclosure.

[0013] Figure 2 This is an exploded view of an exemplary article of manufacture according to at least one embodiment of the present disclosure.

[0014] Figure 3 This is a top perspective exploded view of an exemplary hard disk drive cover and disk drive assembly incorporating the article described herein, according to at least one embodiment of this disclosure.

[0015] Figure 4 This is a perspective view of the top side of an exemplary USB flash drive incorporating the article described herein, according to at least one embodiment of this disclosure.

[0016] Figure 5 Selected operations of an exemplary method for forming an article of article according to at least one embodiment of the present disclosure are shown.

[0017] Figure 6 This is an exemplary scanning electron microscope (SEM) image (scale bar: 1 μm) of an exemplary electroless NiB (ENB) coated housing according to at least one embodiment of the present disclosure.

[0018] Figure 7A Exemplary ENB-coated housings and comparative housings at 25°C are exemplary temperature profiles of at least one embodiment of this disclosure.

[0019] Figure 7B Exemplary temperature profiles of an exemplary ENB-coated housing and a comparative housing at 40°C, according to at least one embodiment of this disclosure.

[0020] Figure 8 Exemplary data on the abrasion resistance of an exemplary ENB-coated housing and a comparative housing according to at least one embodiment of this disclosure are shown.

[0021] Figure 9A This is an exemplary image showing a comparison of oil contamination on a coated casing.

[0022] Figure 9B This is an exemplary image showing an exemplary ENB-coated housing free of oil contamination according to at least one embodiment of the present disclosure.

[0023] For ease of understanding, the same reference numerals are used where possible to denote the same elements common in the accompanying drawings. It is conceivable that elements disclosed in one embodiment may be advantageously used in other embodiments without specific description. Detailed Implementation

[0024] Embodiments of this disclosure generally relate to housings and enclosures for electronic devices and memory devices, and more specifically to such housings and enclosures having a nickel-boron coating and methods for forming such nickel-boron coatings. The inventors have discovered that, compared to conventional housings, nickel-boron (NiB) coated housings / enclosures have, for example, improved thermal properties, increased contact area for improved heat dissipation, scratch and abrasion resistance, and improved durability in the presence of grease and oil. In some examples, articles such as housings and enclosures for products such as solid-state drives (SSDs), hard disk drives (HDDs), radiator products, and retail packaging (RPGs) are provided, comprising a NiB coating on at least a portion of the surface of a substrate housing or enclosure. The NiB coating may be a NiB alloy or a material having about 95% or more Ni and 5% or less B. In some embodiments, the NiB alloy or material can be deposited on the substrate surface by an electroless deposition technique including the use of an acidic bath in the presence of a suitable reducing agent.

[0025] In use, the NiB coating described herein can, for example, dissipate heat from semiconductor junctions, thereby improving device lifespan and efficiency. Compared to conventional coated housings, enclosures, and packages for memory devices and electronic devices, the novel and improved coated housings, enclosures, and packages described herein offer improved other properties (e.g., scratch resistance, abrasion resistance, and water repellency). Furthermore, the electrodeposition-free process described herein improves the thermal, surface, and tribological properties of NiB-coated articles and NiB-coated substrates compared to conventional coatings.

[0026] Conventional techniques for depositing nickel-boron materials are unsuitable for housings or enclosures of electronic and memory devices. For example, conventional techniques typically involve using an alkaline bath with a borohydride reducing agent. Under such alkaline conditions (pH 10-14), metallic substrates, such as aluminum-containing substrates, are unstable and begin to dissolve. Furthermore, conventional NiB coatings will have other materials such as thallium or gold to stabilize the coating, and the resulting NiB coating is amorphous. In contrast, the NiB coating formed by the method described herein exhibits crystalline nickel peaks.

[0027] Furthermore, conventional NiB deposition techniques also emphasize heat treatment processes to obtain the desired hardness, corrosion resistance, and other properties. In contrast, the embodiments described herein do not involve such heat treatment processes.

[0028] Embodiments of the present invention generally relate to housings and enclosures for electronic devices and memory devices. Such articles described herein exhibit improved thermal, mechanical, and surface properties compared to prior art housings and enclosures.

[0029] Figure 1A This is a cross-section of an exemplary article 100 according to at least one embodiment. Article 100 may be a structure, for example, for encapsulating, covering, surrounding, and / or accommodating at least a portion of a memory device, electronic device, component used with a memory device, component used with an electronic device, and / or various other devices / products. Article 100 may be a housing, enclosure, shell, panel, base, cover, or any other suitable structure for encapsulating, covering, surrounding, and / or accommodating at least a portion of a device or product. Generally, article 100 comprises at least two components.

[0030] Article 100 includes a first component 101 (or substrate), which may be made of or comprise metals or metal alloys, such as aluminum (Al), stainless steel, iron, zinc, chromium, magnesium, brass, cobalt, copper, alloys thereof, or combinations thereof. The first component 101 has a first surface 105 and a second surface 110. The second surface 110 may be a surface on a memory device, electronic device, heat sink device, or a component used with a memory device, electronic device, heat sink device, or other device / product. The first component 101 may have any suitable shape or size to, for example, encapsulate, cover, surround, and / or accommodate at least a portion of a memory device, electronic device, heat sink device, component used with a memory device, component used with an electronic device, component used with a heat sink device, and / or various other devices / products. The thickness of the first component 101 can be from about 100 micrometers (μm) to about 25,000 μm, such as from about 250 μm to about 5,000 μm, such as from about 1,000 μm to about 2,500 μm, such as from about 2,500 μm to about 10,000 μm, such as from about 5,000 μm to about 20,000 μm. Larger or smaller thicknesses for the first component 101 are also contemplated.

[0031] Article 100 also includes a second component 115 (or coating) disposed on at least a portion of the first surface 105 of the first component 101. For example... Figure 1A As shown, only a single second component 115 is disposed on the surface of the substrate. It is also contemplated that multiple second components are disposed on the surface of the first component. Here, for example, and as... Figure 1BAs shown in article 150, a second component 115a is disposed on at least a portion of a first surface 105 of a first component 101, and a second component 115b is disposed on at least a portion of a second surface 110 of a first component 101. Unless the context otherwise requires, references to the second component 115 herein shall include separate references to the second components 115a and 115b.

[0032] Compared to conventional material coatings, the second component 115 is a coating used, for example, to increase the contact area with the component to improve heat dissipation and to improve scratch resistance and abrasion resistance. The second component 115 may be a composition comprising nickel (Ni) and boron (B), such as a NiB alloy, a material comprising Ni and B, a reaction product comprising Ni and B, or a combination thereof. In some embodiments, and as described below, the second component 115 (e.g., a NiB alloy or a material comprising Ni and B) may be deposited on one or more surfaces of the first component 101 using an electroless deposition technique involving the use of an acidic bath in the presence of a suitable reducing agent. Each of the first component 101 and the second component 115 may individually be a single layer or multiple layers. In some embodiments, articles 100 and 150 are coated substrates comprising a substrate (e.g., the first component 101) and one or more layers comprising nickel and boron (e.g., the second component 115). For example, and in some embodiments, the coated substrate comprises a metal housing for housing an electronic device (corresponding to the first component 101) and also includes a coating disposed on at least a portion of the metal housing (corresponding to the second component 115).

[0033] Based on the total amount of Ni and B in the second component 115 (not exceeding 100 wt%), the weight percentage of Ni in the second component 115 may be about 90 wt% or greater, such as about 91 wt% to about 99 wt%, such as about 92 wt% to about 98 wt%, such as about 93 wt% to about 97 wt%, such as about 94 wt% to about 96 wt%. In at least one embodiment, based on the total amount of Ni and B in the second component 115, the weight percentage of Ni in the second component 115 is about 95 wt% to about 99 wt%, such as about 95 wt% to about 97 wt% or about 96 wt% to about 98 wt%. The weight percentage of Ni in the second component 115 on the specified material surface is determined using energy-dispersive X-ray spectroscopy (EDX) according to ASTM E1508-12a.

[0034] Based on the total amount of Ni and B in the second component 115, the weight percentage of B in the second component 115 may be about 10% or less, such as about 1 wt% to about 9 wt%, such as about 2 wt% to about 8 wt%, such as about 3 wt% to about 7 wt%, such as about 4 wt% to about 6 wt%. In at least one embodiment, based on the total amount of Ni and B in the second component 115, the weight percentage of B in the second component 115 is about 1 wt% to about 5 wt%, such as about 3 wt% to about 5 wt%, or about 2 wt% to about 4 wt%. The weight percentage of B in the second component 115 is determined using EDX spectroscopy according to ASTM E1508-12a.

[0035] The thickness of the second component 115 (or coating) may be about 20 μm or less, such as about 15 μm or less, such as about 1 μm to about 10 μm, such as about 2 μm to about 9 μm, such as about 3 μm to about 8 μm, such as about 4 μm to about 7 μm, such as about 5 μm to about 6 μm. Larger or smaller thicknesses for the second component 115 are also contemplated.

[0036] In some embodiments, a third component (not shown), such as a metal layer, may be disposed between at least a portion of the first component 101 and a portion of the second component 115. The third component may be in the form of a layer comprising zinc or a zinc-containing material. The thickness of the third component (if present) may be about 3 μm or less, such as about 2 μm or less, such as about 0.05 μm to about 2 μm, such as about 0.5 μm to about 1 μm, such as about 1 μm to about 3 μm. Larger or smaller thicknesses are contemplated for the third component.

[0037] Compared to conventional housings, enclosures, and covers discussed below, the articles and coated substrates described herein, such as article 100 or article 150, include a first component 101 and a second component 115 (e.g., a NiB coating) disposed thereon. The articles or coated substrates described herein (e.g., article 100 and article 150) may possess one or more of the following properties:

[0038] The article or coated substrate may have an average surface roughness of about 0.1 μm or greater, such as about 0.2 μm or greater, and / or about 3 μm or smaller, such as about 0.1 μm to about 3 μm, such as about 0.2 μm to about 2 μm, such as about 0.3 μm to about 1 μm. In at least one embodiment, the average surface roughness of the article or coated substrate may be about 0.2 μm or greater, such as about 0.2 μm to about 0.4 μm. Higher or lower average surface roughness of the article or coated substrate is contemplated. Average surface roughness is a measure of the surface profile or finely spaced irregular portions of a surface at different locations on the surface of a specified material and is generally used to indicate the level of roughness. Average surface roughness is measured using a Mitutoyo surface profile measuring instrument according to ISO 4287:1997.

[0039] The article or coated substrate may have a scratch width of about 100 μm or greater, such as about 125 μm or greater, such as about 150 μm or greater, such as about 175 μm or greater, such as about 185 μm or greater. In at least one embodiment, the article or coated substrate has a scratch width of about 20 μm to about 100 μm, such as about 25 μm to about 95 μm, such as about 30 μm to about 90 μm, such as about 35 μm to about 85 μm, such as about 40 μm to about 80 μm, such as about 45 μm to about 75 μm, such as about 50 μm to about 70 μm, such as about 55 μm to about 65 μm. In some embodiments, the article or coated substrate has a scratch width of about 65 μm to about 75 μm. Higher or lower scratch widths of the article or coated substrate are contemplated. Scratch width is a measure of the width of a groove under a constant applied load and is used to indicate scratch resistance; a lower value indicates higher scratch resistance of the specified material. Scratch width is determined using a Taber scratch tester according to ISO 4586-2.

[0040] The article or coated substrate may have a scratch hardness of about 0.5 gigapascals (GPa) or less and / or about 0.4 GPa or less, such as about 0.3 GPa or less and / or about 0.2 GPa or less, such as about 0.05 GPa to about 0.5 GPa, such as about 0.1 GPa to about 0.4 GPa, such as about 0.15 GPa to about 0.35 GPa, such as about 0.2 GPa to about 0.35 GPa, such as about 0.3 GPa to about 0.35 GPa, such as about 0.2 GPa to about 0.3 GPa, such as about 0.25 GPa to about 0.3 GPa. In at least one embodiment, the scratch hardness of the article or coated substrate is about 0.5 GPa or greater, such as about 0.55 GPa or greater, such as about 1 GPa to about 4 GPa, such as about 1.5 GPa to about 3.5 GPa, such as about 1.75 GPa to about 3 GPa, such as about 1.75 GPa to about 2.75 GPa, or about 2 GPa to about 2.5 GPa. Higher or lower scratch hardness of the article or coated substrate is contemplated. Scratch hardness is a measure of scratch resistance; a higher value indicates higher scratch resistance of the specified material. Scratch hardness is determined using a Taber scratch tester according to ISO 4586-2.

[0041] The article or coated substrate may have a coefficient of friction (unitless) of about 0.5 or less, such as about 0.4 or less, such as about 0.35 or less, such as about 0.3 or less, such as about 0.25 or less, such as about 0.2 or less, such as about 0.15 or less, such as about 0.1 or less. In at least one embodiment, the coefficient of friction of the article or coated substrate is about 0.01 to about 0.3, such as about 0.05 to about 0.25, or about 0.05 to about 0.1, or about 0.1 to about 0.2. Higher or lower coefficients of friction of the article or coated substrate are contemplated. The coefficient of friction of an article is a measure of abrasion resistance; a lower value indicates higher abrasion resistance of the specified material. The coefficient of friction is determined according to ASTM G133 using a pin-disc abrasion tester.

[0042] The article or coated substrate may have a thermal conductivity of about 10 W / m Kelvin (W / (mK)) or greater, such as about 25 W / mK or greater and / or about 75 W / mK or less, such as about 30 W / mK to about 60 W / mK, such as about 35 W / mK to about 50 W / mK, such as 35 W / mK to about 40 W / mK, or about 40 W / mK to about 45 W / mK. In at least one embodiment, the thermal conductivity of the article or coated substrate is about 30 W / mK to about 40 W / mK or about 30 W / mK to about 50 W / mK. Higher or lower thermal conductivity of the article or coated substrate is contemplated. Thermal conductivity measures the degree to which a given material conducts heat. Thermal conductivity is determined according to ISO 22007-2 using a Hotdisk TPS 2500S thermal constant analyzer.

[0043] The article or coated substrate may have a contact angle of about 100° or greater, such as about 100° to about 150°, such as about 105° to about 145°, such as about 110° to about 140°, such as about 115° to about 135°, such as about 120° to about 130°. In at least one embodiment, the contact angle of the article or coated substrate is about 100° to about 135°, such as about 105° to about 130°, such as about 110° to about 125°, such as about 115° to about 120°. In some embodiments, the contact angle of the article or coated substrate is about 110° or greater, such as about 110° to about 135°. The contact angle is a quantitative measure of the wettability or hydrophobicity of a material. The contact angle is measured using a Rame-Hart goniometer according to ASTM D7334-08.

[0044] In at least one embodiment, the article or coated substrate has: a thermal conductivity of about 30 W / mK to about 40 W / mK; a scratch width of about 65 μm to about 75 μm; a scratch hardness of about 1.5 GPa to about 2.5 GPa; a coefficient of friction of about 0.05 to about 0.1; a contact angle of about 100° to about 130°; and / or a surface roughness of about 0.2 μm to about 0.4 μm.

[0045] As described above, the articles of manufacture or coated substrates (e.g., articles 100 and 150) described herein may be structures for encapsulating, covering, surrounding, and / or accommodating at least a portion of memory devices, electronic devices, components used with memory devices, components used with electronic devices, and / or various other devices / products. Such articles of manufacture or coated substrates may be housings, enclosures, shells, panels, bases, covers, or any other suitable structures for encapsulating, covering, surrounding, and / or accommodating at least a portion of a device or product.

[0046] Illustrative but non-limiting examples of electronic devices, memory devices, and other devices that can be used with the articles of manufacture or coated substrates described herein include hard disk drives (HDDs), solid-state drives (SSDs), universal serial bus (USB) flash drives, laptop computer cases, keyboards, mice, SSD packaging, HDD packaging, sensor covers, camera covers, Wi-Fi routers, car audio systems, CPU covers, plastic cases for electrical and electronic products, and components thereof. Also included are retail packaged (RPG) products, such as USB connectors and their components, and heat sink products, such as heat exchangers, heat pipes, microchannels, pin fins, and their components.

[0047] Figure 2 This is an exploded view of an exemplary electronic package in the form of a solid-state drive cover and assembly 200 according to at least one embodiment. The cover and assembly include a printed circuit board (PCB) layer 201 on which optional components are mounted. The PCB layer 201 has a top surface 201a and a bottom surface 201b. A first cover 205 (or housing) is disposed on at least a portion of the top surface 201a of the PCB layer 201. A second cover 210 (or housing) is disposed on at least a portion of the bottom surface 201b of the PCB layer 201.

[0048] A first coating 215a comprising Ni and B may be disposed between the top surface 201a of the PCB layer 201 and the bottom surface 205b of the first cover 205. The first coating 215a may be disposed on at least a portion of the top surface 201a of the PCB layer 201 and / or on at least a portion of the bottom surface 205b of the first cover 205. A second coating 215b comprising Ni and B may be disposed between the bottom surface 201b of the PCB layer 201 and the top surface 210a of the second cover 210. The second coating 215b may be disposed on at least a portion of the bottom surface 201b of the PCB layer 201 and / or on at least a portion of the top surface 210a of the second cover 210. In some examples, a liquid thermal interface material (shown as a circular disk 220) may be used with the articles described herein.

[0049] In some embodiments, a coating containing Ni and B (not shown) may be applied to at least a portion of the top surface 205a of the first cover 205, to at least a portion of the bottom surface 210b of the second cover 210, or to both. Figure 2 The various coatings and housings / caps shown may correspond to article 100 or article 150. For example, a first coating 215a disposed on at least a portion of the bottom surface 205b of the first cap 205 corresponds to article 100 or article 150.

[0050] Figure 3This is a top perspective exploded view of an exemplary hard disk drive cover and disk drive assembly 300 according to at least one embodiment. The hard disk drive cover and assembly includes a cover 310 having an outer surface 315 and a base assembly. At least a portion of the base assembly 305, cover 310, and / or outer surface 315 may include the aforementioned article 100 or 150. The inner surface of the hard disk drive cover and other portions of the disk drive assembly 300 may include the aforementioned article 100 or 150.

[0051] Figure 4 This is a perspective view of the top side of an exemplary USB flash drive 400 incorporating the articles described herein, according to at least one embodiment. The USB flash drive 400 includes a cover 410 that encloses, covers, surrounds, and / or accommodates at least a portion of a USB device 405. At least a portion of the cover 410 may include the articles 100 or 150 described above. Other portions, such as the inner surface of the USB flash drive 400, may include the articles 100 or 150 described above.

[0052] Figures 2 to 4 The electronic and memory devices shown are non-limiting examples of the use of the articles of manufacture and coated substrates described herein, and are not intended to limit the scope of embodiments of this disclosure.

[0053] Embodiments of this disclosure also relate to methods for preparing articles or coated substrates, such as article 100 or article 150. Generally, and in some embodiments, at least a portion of the substrate (or first component 101) may be sequentially contacted with various mixtures or compositions to form a layer comprising nickel and boron (or second component 115) on the substrate. The methods described herein enable, for example, uniform or substantially uniform coating thickness of a NiB-containing layer on a substrate having various shapes or morphologies, and enable mass production of articles.

[0054] Figure 5Selected operations of an exemplary method 500 for forming an article of article according to at least one embodiment are shown. The method begins at operation 510 with cleaning of a substrate (or first component 101) to remove, for example, oil, grease, wax, metal shavings, dirt particles, and / or other contaminants present on the substrate. The substrate may comprise or be made of a suitable metal and / or metal alloy for housings and enclosures, such as Al, stainless steel, iron, zinc, chromium, magnesium, brass, cobalt, copper alloys thereof, or combinations thereof. The cleaning process of operation 510 includes introducing an alkaline bath into the substrate under cleaning conditions. The cleaning conditions of operation 510 may include temperatures ranging from about 10°C to about 50°C, about 20°C to about 40°C, and about 25°C to about 35°C; pressures ranging from about 400 Torr to about 1200 Torr, such as about 600 Torr to about 1000 Torr, and about 700 Torr to about 800 Torr; and / or durations ranging from about 30 minutes to about 10 hours, such as about 1 hour to about 5 hours, and such as about 2 hours to about 3 hours. Here, the substrate may be submerged or otherwise immersed in an alkaline bath. Additionally or alternatively, the alkaline bath may be sprayed onto the substrate. The alkaline bath typically has a pH of about 8 to about 12, such as about 9 to about 11, and may be an aqueous solution containing detergents, soap-oil cleaners, or combinations thereof. The alkaline bath may contain suitable materials such as soap-oil, detergents, and combinations thereof. The ratio of soap-oil to detergent may be about 5:1 to about 1:5, such as about 3:1 to about 1:3, such as about 2:1 to about 1:2, such as about 1:1.

[0055] Once the substrate has been cleaned to the desired specifications, it may optionally be washed with water, sprayed with water, or immersed in water to remove any residual alkaline bath. Washing may be performed for a period of approximately 30 minutes or less, such as approximately 5 to approximately 10 minutes. Additionally or alternatively, and after the cleaning process of operation 510 (using optional washing with water), the substrate may be degreased using one or more organic solvents. Suitable organic solvents for degreasing the substrate include, but are not limited to, ketone solvents such as acetone and / or methyl ethyl ketone; and alcohol solvents such as ethanol and / or isopropanol. Combinations of organic solvents may be used. For example, a ~1:1 mixture of acetone and ethanol may be used to degrease the substrate. If desired, this degreasing operation may be performed for a duration of approximately 1 hour or less, such as approximately 30 minutes or less, such as approximately 20 minutes or less.

[0056] Method 500 further includes polishing the substrate at operation 520. The polishing process of operation 520 may include introducing a polishing solution / mixture into the substrate under polishing conditions to form a polished substrate. The polishing solution / mixture may contain suitable materials to polish the metals and / or metal alloys of the substrate. The polishing solution may be an aqueous solution containing one or more acids (inorganic acids), such as HNO3, H2SO4, H2CrO4, HCl, H3PO4, or suitable combinations thereof. Non-limiting examples of polishing solutions or mixtures include varying proportions of HNO3, H2SO4, and water, such as about 40 vol% to about 60 vol% of HNO3, 20 vol% to about 30 vol% of H2SO4, and the remainder of the solution being water. The polishing solution or mixture may have a pH of about 2 to about 6, such as about 3 to about 5. Polishing conditions for operation 520 may include temperatures ranging from about 10°C to about 50°C, such as about 20°C to about 40°C, such as about 25°C to about 35°C; pressures ranging from about 400 Torr to about 1200 Torr, about 600 Torr to about 1000 Torr, about 700 Torr to about 800 Torr; and / or durations ranging from about 1 minute to about 20 minutes, such as about 3 minutes to about 15 minutes, such as about 3 minutes to about 5 minutes, or about 5 minutes to about 10 minutes. Here, the substrate may be submerged or otherwise immersed in the polishing solution / mixture. Additionally or alternatively, the polishing solution / mixture may be sprayed onto the substrate.

[0057] In some embodiments, the polishing solution or mixture may additionally or alternatively contain various water-soluble mineral salts, such as sulfates and bisulfates of alkali metals and ammonium. Illustrative but non-limiting examples include sodium sulfate, sodium bisulfate, potassium sulfate, potassium bisulfate, ammonium sulfate, and ammonium bisulfate. Mixtures of such salts may be used. The polishing solution may additionally or alternatively contain salts of organic acids. Such organic salts can help control the oxidation and decomposition of various substances in the polishing solution. Illustrative but non-limiting examples of organic salts may include alkali metal salts or ammonium salts of acetic acid, citric acid, tartaric acid, gluconic acid, lactic acid, propionic acid, or mixtures thereof. Non-limiting examples include sodium tartrate, sodium gluconate, potassium citrate, potassium gluconate, potassium lactate, etc.

[0058] Method 500 also includes depositing a zinc-containing layer on the substrate at operation 530. This process is referred to as "galvanizing" and typically involves immersing the substrate in an acidic or alkaline zinc bath to deposit a thin zinc-containing layer. The resulting zinc-containing layer (or zinc plating) minimizes oxidation on the substrate surface. A typical process sequence for depositing the zinc-containing layer typically includes zinc plating; chemical stripping of the zinc plating; and re-galvanizing of the surface. This secondary zinc plating process can be performed prior to the electroless NiB deposition discussed below to, for example, facilitate NiB plating on the substrate.

[0059] The first galvanizing process of operation 530 includes introducing a galvanizing bath into a polished substrate under the following conditions: a temperature between about 10°C and about 50°C, such as about 20°C to about 40°C; such as about 25°C to about 35°C; a pressure between about 400 Torr to about 1200 Torr, about 600 Torr to about 1000 Torr, about 700 Torr to about 800 Torr; and / or the following durations: about 10 seconds to about 100 seconds, such as about 20 seconds to about 80 seconds, such as about 30 seconds to about 60 seconds, such as about 40 seconds to about 50 seconds. Here, the substrate may be submerged or otherwise immersed in the galvanizing bath. The galvanizing bath includes an aqueous solution of a zinc source (such as zinc hydroxide and / or zinc oxide) and an alkali metal hydroxide such as sodium hydroxide. The galvanizing bath may also include ferric chloride and a tartrate / tartrate ion source (such as a salt of tartaric acid, such as potassium sodium tartrate, also known as rochelle salt)). In some embodiments, the zinc plating bath may contain various amounts of these materials, such as the following formulation ranges: ~250 g / L-325 g / L NaOH, ~5 g / L-12 g / L zinc oxide, ~0.75 g / L-1.5 g / L ferric chloride, and ~0.1 g / L-1 g / L potassium sodium tartrate. Another zinc plating solution that can be used with embodiments of this disclosure includes, for example, U.S. Application Serial No. 10 / 265,864, the entire contents of which are incorporated herein by reference.

[0060] The zinc plating layer formed by the first zinc plating process of operation 530 can be peeled off from the substrate or otherwise removed by immersing the substrate in an acidic zinc bath containing HNO3 and water. In some embodiments, the acidic bath may contain a certain amount of these materials, such as the following formulation range: 20 g / L-80 g / L of HNO3 (nitric acid), with the remainder being water. For example, the acidic bath may include 50% nitric acid and 50% water. The zinc layer can be removed from the substrate using the acidic bath under the following conditions: temperatures ranging from about 10°C to about 50°C, such as about 20°C to about 40°C; such as about 25°C to about 35°C; pressures ranging from about 400 Torr to about 1200 Torr, about 600 Torr to about 1000 Torr, about 700 Torr to about 800 Torr; and / or the following durations: about 10 seconds to about 100 seconds, such as about 20 seconds to about 80 seconds, such as about 30 seconds to about 60 seconds, such as about 40 seconds to about 50 seconds. The second galvanizing process of operation 530 can be performed in the same or similar manner as the first galvanizing process discussed above.

[0061] The zinc-containing layer formed by operation 530 may have a thickness of about 0.05 μm to about 3 μm, such as about 0.1 μm to about 2 μm, but larger or smaller thicknesses of the zinc-containing layer are contemplated.

[0062] Method 500 also includes depositing a composition comprising nickel and boron on a zinc-containing material at operation 540. The Ni and B-containing composition may be a NiB alloy, a Ni and B-containing material, a Ni and B-containing reaction product, or a combination thereof. The Ni and B-containing composition may be in the form of a layer, such as a NiB coating, for example, the second component 115. Operation 540 is an electroless NiB deposition process, which generally refers to an autocatalytic process in which a potential can be generated in a deposition bath (or plating bath) containing nickel ions and other components.

[0063] Operation 540 includes introducing a deposition bath onto a substrate on which a Zn-containing layer is formed under deposition conditions. The deposition conditions of operation 540 may include the following temperatures: greater than about 50°C and / or about 100°C or lower, such as about 55°C to about 80°C, such as about 60°C to about 75°C, such as about 65°C to about 70°C; pressures within the following ranges: about 400 Torr to about 1200 Torr, such as about 600 Torr to about 1000 Torr, such as about 700 Torr to about 800 Torr; and / or the following durations: about 30 minutes or longer, such as about 1 hour to about 3 hours, such as about 1.5 hours to about 2.5 hours. Generally, the substrate is submerged or otherwise immersed in the deposition bath.

[0064] The deposition bath in operation 540 may contain suitable proportions of a Ni source, a boron source, a complexing agent, and a stabilizer. The deposition bath in operation 540 may be an aqueous solution / suspension with an acidic pH, such as about 4 to about 6, such as about 4.5 to about 5.5, such as about 4.5 to about 5, or about 5 to about 5.5. In at least one embodiment, the deposition bath for operation 540 has a pH of about 4 to about 5.5, such as about 4 to about 4.5, 4.5 to about 5, or about 5 to about 5.5.

[0065] The nickel source used to operate the deposition bath at 540 may be any suitable Ni source, such as nickel sulfate, nickel acetate, nickel chloride, or combinations thereof. Based on the total weight of the nickel source, boron source, complexing agent, and stabilizer in the deposition bath, the amount of nickel source used in the deposition bath may be from about 25% to about 50% by weight, such as from about 26% to about 38.5% by weight, such as from about 30% to about 36.5% by weight, such as from about 32% to about 34.5% by weight. In some embodiments, the amount of nickel source may be from about 25 g / L to 40 g / L, such as from about 30 g / L to 35 g / L.

[0066] Boron sources that can also act as reducing agents in the deposition bath at 540 may include amines, such as alkylamines, such as dimethylamineborane ((CH3)2NH·BH3), diethylamineborane, trimethylamineborane, triethylamineborane, or combinations thereof. More than one boron source may be used. Based on the total weight of the nickel source, boron source, complexing agent, and stabilizer in the deposition bath, the amount of boron source used in the deposition bath may be from about 1.9 wt% to about 3.1 wt%, such as from about 2 wt% to about 3 wt%, such as from about 2.1 wt% to about 2.9 wt%. In some embodiments, the amount of boron source may be from about 2 g / L to 3 g / L, such as from about 2 g / L to 2.5 g / L or from about 2.5 g / L to 3 g / L.

[0067] The deposition bath of operation 540 may contain one or more complexing agents. The complexing agent used in the deposition bath of operation 540 may include salts of organic acids. Exemplary but non-limiting examples of organic acid salts may include alkali metal salts or ammonium salts of acetic acid, citric acid, tartaric acid, gluconic acid, lactic acid, propionic acid, or combinations thereof. Non-limiting examples include sodium citrate, sodium acetate, sodium tartrate, sodium gluconate, potassium citrate, potassium acetate, potassium gluconate, potassium lactate, and combinations thereof. Based on the total weight of the nickel source, boron source, complexing agent, and stabilizer in the deposition bath, the amount of complexing agent in the deposition bath (e.g., when one or more complexing agents are used in the deposition bath) may be from about 27% to about 39% by weight, such as from about 29% to about 37% by weight, such as from about 31% to about 36% by weight, such as from about 33% to about 34.5% by weight.

[0068] In some embodiments, and when two complexing agents are used in the deposition bath of operation 540, the amount of the first complexing agent used in the deposition bath may be about 10 g / L to 30 g / L, such as about 15 g / L to 25 g / L; and / or the amount of the second complexing agent used in deposition may be about 8 g / L to 30 g / L, such as about 10 g / L to 30 g / L, such as about 15 g / L to 25 g / L.

[0069] The deposition bath in operation 540 may contain one or more stabilizers, such as alcohols (e.g., methanol, ethanol, and / or propanol), lead, ammonia, or combinations thereof. Based on the total weight of the nickel source, boron source, complexing agent, and stabilizer in the deposition bath, the amount of stabilizer in the deposition bath may be from about 28% to about 33% by weight, such as from about 28.5% to about 32% by weight, such as from about 29% to about 31% by weight. In some embodiments, the amount of stabilizer used in the deposition bath may be from about 20 mL / L to 50 mL / L, such as from about 25 mL / L to 45 mL / L, such as from about 30 mL / L to 40 mL / L.

[0070] The weight ratio of nickel source to boron source in the deposition bath of operation 540 can be from about 1:10 to about 1:15, such as from about 1:11 to about 1:14, such as from about 1:12 to about 1:13. In at least one embodiment, the weight ratio of nickel source to boron source in the deposition bath of operation 540 is from about 1:11.7 to about 1:13.3, such as from about 1:12.5 to about 1:13, such as from about 1:11 to about 1:12.5.

[0071] In the deposition bath of operation 540, the weight ratio of nickel source to complexing agent can be from about 9:10 to about 19:20, such as from about 9:11.7 to about 13.5:20, such as from about 9:12.5 to about 11.7:13.5, such as from about 11.7:11.75 to about 13.5:20.

[0072] The weight ratio of nickel source to stabilizer in the deposition bath of operation 540 can be from about 9:12 to about 18:13, such as from about 9.5:11 to about 13:17, such as from about 10:13 to about 11:13. In at least one embodiment, the weight ratio of nickel source to stabilizer in the deposition bath of operation 540 is from about 9.8:11.7 to about 16.6:13.3, such as from about 9.8:10.5 to about 12.5:16.6, such as from about 10:12.5 to about 10.5:13.3.

[0073] In the deposition bath of operation 540, the weight ratio of boron source to complexing agent can be from about 1:12 to about 1:14, such as from about 1:11.7 to about 1:13.3, such as from about 1:12.5 to about 1:13, such as from about 1:11 to about 1:12.5.

[0074] The weight ratio of boron source to stabilizer in the deposition bath of operation 540 can be from about 1:10 to about 1:17, such as from about 1:9.8 to about 1:16.6, such as from about 1:10 to about 1:15, such as from about 1:9.8 to about 1:12.

[0075] The weight ratio of stabilizer to complexing agent in the deposition bath of operation 540 can be from about 9:10 to about 20:13.3, such as from about 9.8:11.7 to about 13.3:15, such as from about 10:12 to about 10:13.3.

[0076] The weight percentages of nickel source, boron source, complexing agent, and stabilizer in the deposition bath of operation 540 are determined based on the weight percentages of the starting materials used to prepare the deposition bath. The weight ratios of the components in the deposition bath of operation 540 are determined based on the weight ratios of the starting materials used to prepare the deposition bath.

[0077] A deposition bath, as described in Operation 540, is formed in an aqueous solution or suspension, such that the nickel source, boron source, complexing agent, and / or other components can be in ionic form, such as Ni ions, organic acid ions, etc. In the solution / suspension, the dimethylamine borane (DMAB) complex can decompose into boric acid, borates, hydrogen, and dimethylamine. Such components can also be present in the deposition bath. The reaction products of the components in the deposition bath can also be present in the deposition bath.

[0078] The electroless NiB deposition in operation 540 enables the uniform or substantially uniform deposition of a NiB-containing layer having the layer thickness described above on a substrate. This NiB coating may have a nanonodular structure or morphology. The exemplary characteristics of the NiB-coated structures (e.g., articles 100 and 150) formed by the operation of method 500 have been described above.

[0079] The following embodiments are provided to provide those skilled in the art with a complete disclosure and description of how to implement and use various aspects of this disclosure, and are not intended to limit the scope of embodiments of this disclosure. Efforts have been made to ensure the accuracy of the figures used (e.g., quantities, dimensions, etc.), but some experimental errors and biases should be taken into account.

[0080] Example

[0081] According to ASTM E1508-12a, the weight percentages of Ni and B on the surface of a specified material were determined using an energy-dispersive X-ray spectrometer (Quanta 650FEG, SEM) on a 10 mm × 10 mm sample. As described below, the average surface roughness was determined using a Mitutoyo surface profiler according to ISO 4287:1997. As described below, the scratch width was determined using a Taber scratch tester according to ISO 4586-2. As described below, the scratch hardness was determined using a Taber scratch tester according to ISO 4586-2. As described below, the coefficient of friction was determined using a pin-disc abrasion tester according to ASTM G133. As described below, the thermal conductivity was determined using a Hotdisk TPS 2500S thermal constant analyzer according to ISO 22007-2. The contact angle was determined using a Rame-Hart goniometer according to ASTM D7334-08.

[0082] 1. An exemplary NiB-coated housing.

[0083] The NiB-coated housing is formed according to the following general procedure. The aluminum alloy substrate (die-cast ADC-12 aluminum alloy) is alkaline cleaned for two hours using a 1:1 ratio of detergent and soap oil cleaner, followed by gentle rinsing with distilled water for 5-10 minutes. The substrate is then degreased for 20 minutes using a 1:1 mixture of acetone and ethanol. The cleaned substrate is then polished by immersing it in a polishing bath (40%-60% nitric acid, 20%-30% sulfuric acid, the remainder distilled water).

[0084] The polished substrate is then treated with a galvanizing step. The galvanizing bath contains approximately 700-980 ml of distilled water containing NaOH (~250 g / L-325 g / L), zinc oxide (~5 g / L-12 g / L), ferric chloride (~0.7 g / L-1.5 g / L), and potassium sodium tartrate (~0.1 g / L-1 g / L). The galvanizing bath is run at approximately 25°C and approximately 760 Torr for approximately 40 seconds. The Zn layer is removed by immersing the substrate in a bath consisting of 50% HNO3 and 50% distilled water at approximately 25°C and approximately 760 Torr for approximately 30 seconds. The substrate is then immersed again in the same galvanizing bath under similar conditions to form a Zn layer on the substrate.

[0085] Electroless NiB deposition was then performed on the substrate on which the zinc layer was deposited. Various exemplary formulations for the electroless deposition bath and the conditions used for deposition are shown in Table 1. During deposition, control factors such as pH and bath temperature were continuously monitored and maintained.

[0086] Table 1

[0087] Exemplary formulation range Exemplary Recipe Nickel sulfate, g / L ～25-40 ～30 Dimethylamineborane, g / L ～2-3 ～2.55 Sodium acetate, g / L ～10-30 ～20 Sodium citrate, g / L ～8-30 ～10 Methanol, mL / L ～20-50 ～25 condition Condition range Exemplary conditions pH ～4-5.5 ～4.5 Bath temperature, ℃ ～55-80 ～70 Deposition time, minutes ～90-150 ～120

[0088] The deposition on the Al shell substrate forms a Ni-B coating with a substantially uniformly distributed nanonodular structure, ~95 wt%-97 wt% Ni and ~3 wt%-5 wt% B, and a thickness of ~6 μm-7 μm. Figure 6 This is an exemplary SEM image of an exemplary electroless NiB (ENB) coated housing captured using a Quanta 650FEG scanning electron microscope. The image shows the nanonodular features of the ENB coating. When mounted onto a thermal interface material (TIM), this nanonodular coating can, for example, increase the contact points between the TIM and the housing, thereby improving heat dissipation.

[0089] Various properties of the exemplary electroless NiB (ENB) coated housing were evaluated relative to the comparative coated housing. These properties, further discussed below, include heat dissipation, scratch resistance, abrasion resistance, oil contamination, thermal conductivity, contact angle, and surface roughness parameters. The comparative coated housing used for evaluation was an epoxy-coated aluminum alloy substrate.

[0090] 2. Exemplary heat dissipation

[0091] To investigate heat dissipation performance, functional thermal plotting was performed on an exemplary ENB-coated housing and a control coated housing (epoxy-coated aluminum alloy substrate) using VDBench software. The thermal plotting measured the thermal behavior of the coated housing under controlled airflow. The experimental setup involved attaching thermocouples to the hottest points on the coated housing (designated as hotspots T1, T2, T3, and T4); performing thermal scans; and recording temperature readings. Exemplary test conditions used for heat dissipation evaluation are shown in Table 2.

[0092] Table 2

[0093] Environmental conditions ~25℃ and ~40℃ Driver test conditions 100% Sequential Write Functionality Temperature scan T-type thermocouple Airflow control 2.3 m / s, using a wind tunnel Test duration 2 hours, 10-second division

[0094] Figure 7A and Figure 7B Exemplary temperature profiles of an exemplary ENB-coated housing (Example 1) and a comparative coated housing (Comparative Example 1) measured at ~25°C and ~40°C, respectively, at thermocouple controller position T1. Figure 7A and Figure 7B The data shown demonstrates that the exemplary ENB-coated housing effectively dissipates heat. Furthermore, the data proves that the exemplary ENB-coated housing exhibits a significant improvement in heat dissipation compared to the comparative coated housing, showing improvements of ~4.6°C and ~5.7°C at the T1 hot spot on the housing.

[0095] Table 3 shows exemplary data on the temperature reduction (AT) of the exemplary ENB-coated housing relative to the contrast-coated housing, for each thermocouple at different hot spots on the housing. T1, T2, T3, and T4 refer to the positions of the thermocouples at the hottest spots. The NAND point refers to the positions of the thermocouples at points T2 and T4. The controller point refers to the position of the thermocouple at point T1, and the secondary or back side of the controller refers to the position at point T3.

[0096] For example, and using Figure 2 The top surface 201a of PCB layer 201 has NAND (T2) and controller (T1) components. Each hot spot is fixed to the top surface 205a of the first cover 205 by a thermocouple. The bottom surface 201b of PCB layer 201 only has NAND components. The corresponding thermocouple T4 is located on the bottom surface 210b of the second cover 210. Although the controller is not placed on the bottom surface 201b of PCB layer 201, the controller hot spot located on the top surface 201a of PCB layer 201 affects the bottom surface 210b of the second cover 210, and therefore T3 is located on the bottom surface 210b of the second cover 210.

[0097] Table 3

[0098] thermocouple Environment (°C) Comparative Example 1 (°C) Example 1 (°C) ΔT (°C) T1 (Controller Point - Top) 40 57.6 51.9 5.7 T2 (NAND point) 40 52.0 47.9 4.1 T3 (Controller Point - Bottom) 40 53.2 49.8 3.4 T4 (NAND point) 40 52.8 49.6 3.2 T1 (Controller Point - Top) 25 43.6 39.0 4.6 T2 (NAND point) 25 38.0 34.2 3.8 T3 (Controller Point - Bottom) 25 39.3 36.4 2.7 T4 (NAND point) 25 38.6 36.2 2.4

[0099] Overall, the data in Table 3 demonstrate that the exemplary ENB coating has a significant impact on reducing component junction temperature and housing temperature. For example, ΔT in the range of approximately 2.4°C to approximately 5.7°C indicates a significant improvement in heat dissipation of the exemplary ENB-coated housing compared to the comparative coated housing. The ~10%-12% improvement in heat dissipation of the ENB-coated housing compared to the comparative coated housing indicates that the ENB-coated housing can improve the lifespan of various components within and / or around the housing.

[0100] 3. Exemplary tribological properties and other properties

[0101] Conventional housings suffer from high rejection rates due to various reasons, including poor scratch resistance, poor abrasion resistance, and oil contamination. These production losses result in high manufacturing costs and waste. The implementation scheme described herein addresses these and other problems.

[0102] The scratch resistance properties (such as scratch width and scratch hardness) of an exemplary ENB-coated housing and a comparative coated housing were investigated. The comparative coated housing studied was an epoxy-coated aluminum substrate. The scratch resistance properties of the coated housing were determined using a Taber 550 / 551 scratch tester according to ISO 4586-2. Here, a substantially flat 70mm × 70mm NiB-coated sample was mounted on a scratch test bench for scratching under applied load.

[0103] The coated housing was plowed with a diamond tool (0.5 kg applied load, constant speed) and then observed under a microscope. The control coated housing showed poor scratch resistance under the 0.5 kg applied load, which is likely due to the viscoelastic properties of the epoxy polymer. Under the same test conditions, the exemplary ENB-coated housing showed a significant improvement in scratch resistance performance (scratch width and scratch hardness). For example, the control coated housing exhibited a scratch width of 180 μm-190 μm and a scratch hardness of 0.2 GPa-0.5 GPa, while the exemplary ENB-coated housing showed a scratch width of approximately 65 μm to approximately 75 μm and a scratch hardness of approximately 1.5 GPa to approximately 2.5 GPa. This test shows that the scratch width is significantly improved by approximately 60%-70% compared to the control coated housing. In addition, the scratch hardness is significantly improved. Here, the scratch hardness of the exemplary ENB-coated housing is approximately 12 times or more higher than that of the control coated housing. Overall, the results demonstrate that the exemplary ENB-coated housing exhibits significantly higher scratch resistance compared to conventional housings. The data also show that the ENB coating eliminates or at least reduces drive rejection (yield loss) due to scratch resistance performance.

[0104] Abrasion resistance was also evaluated to investigate the durability and surface resilience of, for example, the exemplary ENB-coated housing relative to the control housing. Abrasion resistance was measured by determining the coefficient of friction (CoF) of the coating under normal load. Generally, a low CoF is desirable for the coating. The coefficients of friction for the exemplary ENB-coated housing and the control housing were determined according to ASTM G133 and measured using a DUCOM POD 4.0. Here, a flat sample (70 mm × 20 mm) of a NiB-coated substrate was mounted on a worktable. The CoF test involved placing the sample under study under the reciprocating motion of an EN52100 ball (10 mm diameter). At a frequency of 1 Hz, the ball applied a load of 0.5 kg to the surface of the coating, with a sliding distance of 10 mm. Figure 8 Exemplary data on CoF of an exemplary ENB-coated housing (Example 1) and a comparative coated housing (Comparative Example 1) are shown.

[0105] like Figure 8As shown, the contrast-coated housing exhibits an increased coefficient of friction of up to approximately 0.5. Visually, the coating on the contrast-coated housing is prone to deformation, resulting in very high friction on its surface. Under the same test conditions, the exemplary ENB-coated housing demonstrates a significantly lower coefficient of friction of approximately 0.05, along with negligible wear or visual deformation after 900 seconds of sliding time. That is, the ENB coating results in a CoF five times better than the conventionally coated housing without any defects or deformation. Without being bound by theory, it is believed that the improved coefficient of friction of the exemplary ENB-coated housing relative to the contrast-coated housing is attributed to, for example, the lubricating behavior of boron and the uniform coating of the exemplary ENB-coated housing.

[0106] This superior abrasion resistance and CoF performance can be achieved through the ENB-coated articles and ENB process described herein. Overall, the results show that the exemplary ENB-coated housing described herein exhibits very high abrasion resistance compared to conventional housings. The ENB coating can eliminate or at least reduce drive rejection due to wear-induced production losses.

[0107] Oil contamination is another problem that occurs during manufacturing and leads to the rejection of memory drives and other devices. Oil contamination can be attributed to curing conditions under which conventional housings tend to expose silicone oil seepage on their surfaces.

[0108] For example, in Figure 2 A liquid thermal interface material (LTIM), shown as a circular disk, can be applied to the surface of the housing. The LTIM can be made of an elastomer-type material containing a silicone dielectric. The LTIM is used to transfer heat from hot components to the environment through contact with the housing. Once the LTIM is applied to the housing, the PCB with the entire driver assembled can be cured in an oven at 100°C for approximately 30 minutes. After curing, the epoxy-coated housing exhibits visible oil contamination. In contrast, the ENB-coated housing of this disclosure does not exhibit visible oil contamination or traces.

[0109] Figure 9A This is an image showing a contrasting casing with visible oil contamination / leakage (indicated by arrows). Typically, this type of oil seepage requires cleaning the casing or enclosure with isopropyl alcohol to remove the oil contamination. In contrast, and as... Figure 9B As shown in the images, the exemplary ENB-coated housing exhibits no visible oil contamination or leakage. Therefore, the ENB coating can facilitate higher production volumes and lower yield losses, for example, by eliminating the isopropyl alcohol cleaning step.

[0110] Table 4 summarizes the performance of the exemplary ENB-coated housing described herein relative to the comparative coated housing (epoxy-coated housing). Thermal conductivity was determined according to ISO 22007-2 and measured using a Hot Disc TPS 2500s thermal conductivity analyzer. To measure thermal conductivity, a Kapton insulated TPS sensor was placed between two identical NiB-coated (70mm × 70mm) samples. Contact angle was determined according to ASTM D7334-08 and measured using a Rame-Hart goniometer. A flat 70 × 70mm Ni-B-coated substrate was mounted on a worktable, and a controlled amount of 5 μL of water was dispensed onto the Ni-B surface using a nozzle. The contact angle between the solid surface and the liquid medium was measured and discussed using droplet images from the build software. Surface roughness was determined according to ISO 4287:1997 and measured using a Mitutoyo SJ410 surface roughness profiler with a 60° / 2μm stylus indenter under a measuring force of 0.75 mN. A 70mm × 70mm NiB coated substrate was placed on a granite workbench, and then the average roughness value was obtained by tracking the 4.0mm stroke length of the indenter on the surface.

[0111] Table 4

[0112] performance Comparative Coating Examples Exemplary ENB-coated housing Thermal conductivity, W / mK 10-25 ～30-40 Scraping width, μm 180-190 ～65-75 Scratch hardness, GPa 0.2-0.5 ～1.5-2.5 coefficient of friction, dimensionless 0.4-0.5 ～0.05-0.1 Contact angle, degrees (°) 95-105 (hydrophobic) ~100-135 (hydrophobic) Surface roughness, μm 0.1-0.3 ～0.2-0.4 Oil seepage pollution yes no

[0113] The data in Table 4 indicate the thermal, mechanical, and surface properties of the ENB-coated housing described herein. For example, the exemplary ENB-coated housing exhibits a thermal conductivity increase of approximately 20%–30% or more compared to the comparative coated housing. As shown in Table 4, the surface roughness of the ENB-coated surface remains nearly similar to that of the epoxy-coated surface, but may be slightly improved.

[0114] The hydrophobicity or water-repellency of the coating enables the coated surface to exhibit self-cleaning behavior against various liquid media. Here, hydrophobicity, as measured by the contact angle, is increased to approximately 135°. Therefore, compared to conventional coatings, coating contamination problems can be reduced, and the surface appearance of the exemplary coating can be maintained more intact.

[0115] The embodiments described herein relate generally to housings, enclosures, and packages for, for example, memory devices or electronic devices, and to methods for forming such housings, enclosures, and packages. Overall, the electroless NiB coatings described herein offer superior thermal performance, scratch and abrasion resistance, surface finish, and hydrophobic properties compared to conventional coatings used for housings. Furthermore, exemplary electroless NiB-coated housings show no oil seepage on their surfaces. Data also indicate that the coatings described herein can be used for housings or enclosures of various electronic devices, memory devices, heat sink products, and other devices and products, such as SSD, HDD, and RPG metal housings.

[0116] As used herein, a “composition” may include components of the composition and / or reaction products of two or more components of the composition.

[0117] In the foregoing, reference has been made to embodiments of this disclosure. However, it should be understood that this disclosure is not limited to the specifically described embodiments. Rather, consider any combination of the following features and elements (whether or not related to different embodiments) to implement and practice this disclosure. Furthermore, while embodiments of this disclosure may achieve advantages over other possible solutions and / or over the prior art, whether a particular advantage is achieved by a given embodiment is not a limitation of this disclosure. Therefore, the foregoing embodiments, aspects, features, and advantages are illustrative only and should not be considered as elements or limitations of the appended claims unless expressly stated in the claims. Similarly, reference to “this disclosure” should not be construed as a generalization of any inventive subject matter disclosed herein and should not be considered as elements or limitations of the appended claims unless expressly stated in the claims.

[0118] For the purposes of this disclosure, and unless otherwise specified, all numerical values ​​in the detailed descriptions and claims herein are modified by values ​​indicated by “about” or “approximately”, and take into account experimental errors and variations expected by those skilled in the art. For brevity, only certain ranges are explicitly disclosed herein. However, a range from any lower limit may be combined with any upper limit to enumerate ranges not explicitly enumerated, and a range from any lower limit may be combined with any other lower limit to enumerate ranges not explicitly enumerated, and in the same manner, a range from any upper limit may be combined with any other upper limit to enumerate ranges not explicitly enumerated. Additionally, each point or individual value included within a range, even if not explicitly enumerated, is considered. Thus, each point or individual value may be used as its own lower or upper limit in combination with any other point or individual value or any other lower or upper limit to enumerate ranges not explicitly enumerated.

[0119] As used in this article, the indefinite article “a” or “one” should mean “at least one”, unless otherwise specified or the context clearly indicates otherwise.

[0120] While the foregoing describes embodiments of this disclosure, other and additional embodiments of this disclosure may be contemplated without departing from the basic scope of this disclosure, the scope of which is defined by the appended claims.

Claims

1. An article of article for accommodating at least a portion of an electronic device, the article of article being used with a thermal interface material disposed between the electronic device and the article of article, the article of article comprising: Contains a metal substrate; as well as A layer comprising nickel and boron, said layer being disposed on at least a portion of said metal-containing substrate, said layer having a nanonodular structure morphology and attached to said thermal interface material, wherein: Based on the total amount of nickel and boron in the layer, the amount of nickel in the layer is 95% to 97% by weight, and the total amount of nickel and boron in the layer does not exceed 100% by weight; and Based on the total amount of nickel and boron in the layer, the amount of boron in the layer is 3% to 5% by weight. The article has the following characteristics: Thermal conductivity of 25 W / mK or greater; 0.5 GPa or greater scratch hardness; A coefficient of friction of 0.4 or less; or Their combination; and The layer is not amorphous, and it exhibits crystalline nickel peaks; and The article in question was not heat-treated.

2. The article of claim 1, wherein the article comprises: Scratching width of 180μm or less; 100° or greater contact angle; Surface roughness of 0.1 μm or greater; or Their combination.

3. The article of claim 1 further comprises a zinc-containing layer disposed between at least a portion of the metal-containing substrate and the nickel- and boron-containing layer.

4. The article of claim 1, wherein the article of claim 1 comprises: Thermal conductivity from 30 W / mK to 50 W / mK; Scratching hardness from 1 GPa to 3 GPa; A coefficient of friction of 0.3 or less; or Their combination.

5. The article of claim 4, wherein the article of claim 4 comprises: Scraping width of 100μm or less; 110° or greater contact angle; Surface roughness of 0.2 μm or greater; or Their combination.

6. The article of manufacture according to claim 1, wherein the electronic device comprises a hard disk drive, a solid-state drive, a universal serial bus (USB) flash drive, a laptop computer casing, a keyboard, a mouse, a USB package, an SSD package, an HDD package, a sensor cover, a camera cover, a Wi-Fi router, a car audio system, a CPU cover, a heat pipe, a microchannel, a pin heat sink, or components thereof.

7. The article of claim 1, wherein the metal substrate comprises aluminum, stainless steel, iron, zinc, chromium, magnesium, brass, cobalt, copper alloys thereof, or combinations thereof.

8. An article comprising: Electronic devices; A coated substrate disposed on at least a portion of the electronic device; as well as A thermal interface material disposed between the electronic device and the coated substrate, the coated substrate comprising: Contains a metal substrate; as well as A coating disposed on at least a portion of the metal-containing substrate, the coating having a thickness of 15 μm or less, the coating having a nano-nodular structure morphology and being attached to the thermal interface material, the coating comprising: The coating contains 95% to 97% by weight of nickel, based on the total amount of nickel and boron; and Based on the total amount of nickel and boron in the coating, boron is present in an amount of 3% to 5% by weight, and the total amount of nickel and boron in the coating does not exceed 100% by weight. The coated substrate has: Thermal conductivity of 25 W / mK or greater; 0.5 GPa or greater scratch hardness; A coefficient of friction of 0.4 or less; or Their combination; and The coating is not amorphous, and it exhibits crystalline nickel peaks; and The article in question was not heat-treated.

9. The article of claim 8, wherein: The thermal conductivity of the coated substrate is 30 W / mK to 50 W / mK; The scratch hardness of the coated substrate is 1 GPa to 3 GPa; The coefficient of friction of the coated substrate is 0.3 or less; or Their combination.

10. The article of claim 8, wherein the coated substrate comprises: Scraping width of 100μm or less; 110° or greater contact angle; Surface roughness of 0.2 μm or greater; or Their combination.

11. The article of claim 8, wherein the coated substrate has at least three of the following properties: Thermal conductivity of 30 W / mK to 40 W / mK; Scraping width of 65μm to 75μm; Scratching hardness from 1.5 GPa to 2.5 GPa; A coefficient of friction of 0.1 or less; Contact angle of 110° to 135°; or Surface roughness from 0.2 μm to 0.4 μm.

12. The article of manufacture according to claim 8, wherein the electronic device comprises a hard disk drive, a solid-state drive, a universal serial bus (USB) flash drive, a laptop computer casing, a keyboard, a mouse, a USB package, an SSD package, an HDD package, a sensor cover, a camera cover, a Wi-Fi router, a car audio system, a CPU cover, a heat pipe, a microchannel, a pin heat sink, or components thereof.

13. A method of manufacturing a housing for an electronic device, comprising: A layer containing nickel and boron is formed on a substrate by electroless deposition in a deposition bath. in: The deposition bath is formed from a nickel source, a boron source, and a complexing agent. Based on the total amount of nickel and boron in the layer, the amount of nickel in the layer is 95% to 97% by weight, and Based on the total amount of nickel and boron in the layer, the amount of boron in the layer is 3% to 5% by weight, and The thermal interface material is disposed between the electronic device and the deposited substrate; and The layer described herein has a nanonodular structure and is attached to the thermal interface material; and The layer is not amorphous, and it exhibits crystalline nickel peaks; and The method described herein does not include a heat treatment process; and The pH of the sedimentation bath is 4 to 6.

14. The method of claim 13, wherein: The nickel source comprises nickel sulfate, nickel chloride, nickel acetate, or a combination thereof; and The boron source includes dimethylamineborane, diethylamineborane, trimethylamineborane, triethylamineborane, or combinations thereof.

15. The method according to claim 13, wherein: The electrodeposition is performed at a temperature of 100°C or lower.

16. The method of claim 13, further comprising: The substrate is zinc-plated before the nickel- and boron-containing layer is formed.

17. The method of claim 13, further comprising: Clean the substrate with an alkaline bath; as well as The cleaned substrate is polished using a polishing bath containing one or more inorganic acids, wherein cleaning and polishing are performed prior to the formation of the nickel and boron-containing layer.

18. The method of claim 13, wherein: The weight ratio of the nickel source to the complexing agent used to form the deposition bath is from 9:12.5 to 13.3:

20.

19. The method of claim 13, wherein the layer comprising nickel and boron is 15 μm or less.

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