NICKEL-BORON COATINGS FOR HOUSINGS AND ENCLOSURES
Embodiments of the present disclosure generally relate to housings and enclosures for electronic devices and memory devices, and more specifically to such housings and enclosures having nickel-boron coatings and processes for forming such nickel-boron coatings. In an embodiment is provided an article for housing at least a portion of an electronic device that includes a metal-containing substrate, and a layer comprising nickel and boron, the layer disposed on at least a portion of the metal-containing substrate, wherein: an amount of nickel in the layer is about 95 wt % or more and an amount of boron in the layer is about 5 wt % or less based on the total amount of nickel and boron in the layer. The article has a thermal conductivity of about 25 W/mK or more, a scratch hardness of about 0.5 GPa or more, a coefficient of friction of about 0.4 or less, or combinations thereof.
1 . An article for housing at least a portion of an electronic device, the article comprising:
a metal-containing substrate; and
a layer comprising nickel and boron, the layer disposed on at least a portion of the metal-containing substrate, wherein:
an amount of nickel in the layer is about 95 wt % or more based on a total amount of nickel and boron in the layer, the total amount of nickel and boron in the layer not to exceed 100 wt %; and
an amount of boron in the layer is about 5 wt % or less based on the total amount of nickel and boron in the layer,
the article having:
a thermal conductivity (ISO 22007-2) of about 25 W/mK or more;
a scratch hardness (ISO 4586-2) of about 0.5 GPa or more;
a coefficient of friction (ASTM G133) of about 0.4 or less; or
combinations thereof.
2 . The article of claim 1 , wherein the article has:
a scratch width (ISO 4586-2) of about 180 μm or less;
a contact angle (ASTM D7334-08) of about 100° or more;
a surface roughness (ISO 4287:1997) of about 0.1 μm or more; or
combinations thereof.
3 . The article of claim 1 , further comprising a zinc-containing layer disposed between at least a portion of the metal-containing substrate and the layer comprising nickel and boron.
4 . The article of claim 1 , wherein the article has:
a thermal conductivity (ISO 22007-2) of about 30 W/mK to about 50 W/mK;
a scratch hardness (ISO 4586-2) of about 1 GPa to about 3 GPa;
a coefficient of friction of about 0.3 or less; or
combinations thereof.
5 . The article of claim 4 , wherein the article has:
a scratch width (ISO 4586-2) of about 100 μm or less;
a contact angle (ASTM D7334-08) of about 110° or more;
a surface roughness (ISO 4287:1997) of about 0.2 μm or more; or
combinations thereof.
6 . The article of claim 1 , wherein the electronic device comprises a hard disk drive, a solid state drive, a universal serial bus (USB) flash drive, USB packaging, SSD packaging, HDD packaging, or components thereof.
7 . The article of claim 1 , wherein the metal-containing substrate comprises aluminum, stainless steel, iron, zinc, chromium, magnesium, brass, cobalt, copper alloys thereof, or combinations thereof.
8 . The article of claim 1 , wherein the amount of nickel in the layer is from about 95 wt % to about 97 wt %, and the amount of boron in the layer is from about 3 wt % to about 5 wt %.
9 . An article, comprising:
an electronic device;
a coated substrate disposed on at least a portion of the electronic device, the coated substrate comprising:
a metal-containing substrate; and
a coating layer disposed over at least a portion of the metal-containing substrate, the coating layer having a thickness of about 15 μm or less, the coating layer comprising:
an amount of nickel of about 95 wt % or more based on a total amount of nickel and boron of the coating layer; and
an amount of boron of about 5 wt % or less based on the total amount of nickel and boron in the coating layer, the total amount of nickel and boron in the coating layer not to exceed 100 wt %,
the coated substrate having:
a thermal conductivity (ISO 22007-2) of about 25 W/mK or more;
a scratch hardness (ISO 4586-2) of about 0.5 GPa or more;
a coefficient of friction (ASTM G133) of about 0.4 or less; or
combinations thereof.
10 . The article of claim 9 , wherein:
the thermal conductivity of the coated substrate is about 30 W/mK to about 50 W/m K;
the scratch hardness of the coated substrate is about 1 GPa to about 3 GPa;
the coefficient of friction of the coated substrate is about 0.3 or less; or
combinations thereof.
11 . The article of claim 9 , wherein the coated substrate has:
a scratch width (ISO 4586-2) of about 100 μm or less;
a contact angle (ASTM D7334-08) of about 110° or more;
a surface roughness (ISO 4287:1997) of about 0.2 μm or more; or
combinations thereof.
12 . The article of claim 9 , wherein the coated substrate has at least three of the following properties:
a thermal conductivity (ISO 22007-2) of about 30 W/mK to about 40 W/mK;
a scratch width (ISO 4586-2) of about 65 μm or to about 75 μm;
a scratch hardness (ISO 4586-2) of about 1.5 GPa to about 2.5 GPa;
a coefficient of friction of about 0.1 or less;
a contact angle (ASTM D7334-08) of about 110° to about 135°; or
a surface roughness (ISO 4287:1997) of about 0.2 μm to about 0.4 μm.
13 . The article of claim 9 , wherein the electronic device comprises a hard disk drive, a solid state drive, a universal serial bus (USB) flash drive, USB packaging, SSD packaging, HDD packaging, or components thereof.
14 . A process of making a housing or enclosure for an electronic device, comprising:
forming, by electroless deposition in a deposition bath, a layer comprising nickel and boron on a substrate,
wherein:
the deposition bath is formed from a nickel source, a boron source, and a complexing agent,
an amount of nickel in the layer is about 95 wt % or more based on a total amount of nickel and boron in the layer, and
an amount of boron in the layer is about 5 wt % or less based on the total amount of nickel and boron in the layer.
15 . The process of claim 14 , wherein:
the nickel source comprises nickel sulfate, nickel chloride, nickel acetate, or combinations thereof; and
the boron source comprises dimethylamine borane, diethylamine borane, trimethylamine borane, triethylamine borane, or combinations thereof.
16 . The process of claim 14 , wherein:
the electroless deposition is performed at a temperature of about 100° C. or less; and
a pH of the deposition bath is from about 4 to about 6.
17 . The process of claim 14 , further comprising:
zincating the substrate prior to forming the layer comprising nickel and boron.
18 . The process of claim 14 , further comprising:
cleaning the substrate with an alkaline bath; and
polishing the cleaned substrate with a polishing bath comprising one or more inorganic acids, wherein cleaning and polishing is performed prior to forming the layer comprising nickel and boron.
19 . The process of claim 14 , wherein:
a weight ratio of the nickel source to the boron source used to form the deposition bath is from about 1:11.7 to about 1:13.3; and
a weight ratio of the nickel source to the complexing agent used to form the deposition bath is from about 9:12.5 to about 13.3:20.
20 . The process of claim 14 , wherein the layer comprising nickel and boron is about 15 μm or less.