Electronic device housing having a radio-frequency transmissive component
An electronic device component including a thermoset composite material is described herein. The electronic device component may be a structural component of the housing and define an exterior surface of the housing. The electronic device component may also be transparent to radio-frequency signals.
1. An electronic device comprising:
a housing comprising:
a first housing component formed from a first metal material, configured to operate as an antenna, and defining:
a first exterior surface; and
a first surface extending from the first exterior surface towards an interior volume of the housing and defining a first set of retention features;
a second housing component formed from a second metal material and defining:
a second exterior surface; and
a second surface extending from the second exterior surface and defining a second set of retention features;
a third housing component formed from a thermoset composite material, defining a third exterior surface, bonded to the first and the second housing components, and electrically isolating the first housing component from the second housing component, the thermoset composite material conforming to retention features of each of the first and the second sets of retention features and comprising:
an epoxy-based material; and
10 wt % to 50 wt % of nanosized silica particles dispersed in the epoxy-based material; and
wireless communication circuitry positioned within the housing and operably connected to the first housing component.
2. The electronic device of claim 1 , wherein:
the thermoset composite material has a glass transition temperature ranging from 65° C. to 85° C.
3. The electronic device of claim 2 , wherein:
the second housing component further defines an interior retention feature that protrudes from a portion of an interior surface of the housing; and
the third housing component extends around the interior retention feature.
4. The electronic device of claim 2 , wherein:
the first set of retention features includes a first set of pores
the second set of retention features includes a second set of pores; and
the third housing component extends into the first set of pores and the second set of pores.
5. The electronic device of claim 4 , wherein:
the first housing component includes a first anodization layer that defines the first set of pores; and
the second housing component includes a second anodization layer that defines the second set of pores.
6. The electronic device of claim 1 , wherein the thermoset composite material has an ultimate tensile strength from 30 MPa to 50 MPa and an elongation from 10% to 15%.
7. The electronic device of claim 1 , wherein:
the thermoset composite material has a dielectric constant in a range from 2 to 4 as measured at a frequency of 2.5 GHz.
8. An electronic device comprising:
wireless communication circuitry; and
a housing at least partially enclosing the wireless communication circuitry, the housing comprising:
a first housing component operably coupled to the wireless communication circuitry, formed from a first metal, and defining:
a first portion of a side surface of the electronic device, and
a first bonding surface extending from the first portion of the side surface and defining a first set of retention features;
a second housing component formed from a second metal and defining:
a second portion of the side surface of the electronic device, and
a second bonding surface extending from the second portion of the side surface and defining a second set of retention features; and
a dielectric housing component defining a third portion of the side surface of the electronic device, electrically isolating the first and the second housing components, and engaged with retention features of the first and the second sets of retention features, the dielectric housing component formed from a thermoset composite material comprising:
an epoxy-based polymer; and
10 wt % to 50 wt % of nanosized silica.
9. The electronic device of claim 8 , wherein:
the dielectric housing component has an ultimate tensile strength from 30 MPa to 50 MPa and an elongation from 10% to 15%.
10. The electronic device of claim 9 , wherein:
the second bonding surface is set apart from the first bonding surface by a gap; and
the dielectric housing component is partly positioned within the gap and bonded to each of the first bonding surface and the second bonding surface.
11. The electronic device of claim 10 , wherein:
the first bonding surface further defines a first angled portion;
the second bonding surface further defines a second angled portion that together with the first angled portion defines an interlock feature.
12. The electronic device of claim 10 , wherein:
the housing further comprises:
a first porous anodization layer provided along the first bonding surface that defines the first set of retention features; and
a second porous anodization layer provided along the second bonding surface that defines the second set of retention features; and
the dielectric housing component extends at least partially into pores of each of the first porous anodization layer and the second porous anodization layer.
13. The electronic device of claim 8 , wherein:
at least some of the silica particles have a size in a range from 1 nm to 100 nm.
14. The electronic device of claim 13 , wherein the thermoset composite material further comprises pigment particles having a size less than 20 micrometers.
15. An electronic device comprising:
a housing defining an internal cavity and comprising:
a first metal housing component defining:
a first portion of an exterior surface of the housing; and
a first surface extending from the first portion of the exterior surface and defining a first set of retention features;
a second metal housing component defining:
a second portion of the exterior surface of the housing; and
a second surface extending from the second portion of the exterior surface and defining a second set of retention features; and
a dielectric housing component formed from a thermoset composite material comprising an epoxy matrix and 10 wt% and 50 wt% of nano-sized silica particles dispersed within the epoxy matrix, the dielectric housing component:
defining a third portion of the exterior surface of the housing;
engaged with retention features of each of the first set of retention features and the second set of retention features; and
electrically isolating the first and the second housing components; and
wireless communication circuitry positioned within the internal cavity and operably connected to at least one of the first metal housing component and the second metal housing component.
16. The electronic device of claim 15 , wherein the thermoset composite material has:
a hardness from 70 to 95 on a Shore D hardness scale; and
an impact strength from 50 J/m to 90 J/m.
17. The electronic device of claim 16 , wherein:
a first porous layer defines the first set of retention features;
a second porous layer defines the second set of retention features; and
the dielectric housing component extends into pores of each of the first and the second porous layers.
18. The electronic device of claim 17 , wherein: the first surface further defines a recess that is larger than the pores of the first porous layer.
19. The electronic device of claim 15 , wherein:
the first metal housing component is formed from a first metal;
the second metal housing component is formed from a second metal; and
a bond strength between the thermoset composite material and each of the first and the second metal is greater than 20 MPa and up to 50 MPa as measured with a lap shear test.
20. The electronic device of claim 19 , wherein each of the first metal and the second metal are a same metal.