Thermal management assembly comprising bulk graphene material
A thermal management assembly comprising a bulk graphene material and a metal-based coating layer disposed on opposing surfaces of the bulk graphene core material comprising an agent that is reactive with the graphene to form a carbide. The metal-based coating layer can serve as an outer layer of the assembly or can serve to bond the graphene to other materials encapsulating the graphene core. The metal-based coating layer with the reactive agent provides an assembly exhibiting excellent thermal conductivity properties and greatly improved thermal interface resistance.
1. A thermal management assembly comprising:
a first substrate;
a second substrate;
a bulk graphene material disposed between the first and second substrates, the bulk graphene material selected from pyrolytic graphite, thermal pyrolytic graphite, highly oriented pyrolytic graphite, compression annealed pyrolytic graphite, or a combination of two or more thereof; and
(a) a first thermal bond layer directly bonding a first surface of the bulk graphene material and the first substrate, and (b) a second thermal bond layer directly bonding a second surface of the bulk graphene material and the second substrate, the first and second thermal bond layers each comprising (i) a metal-based material wherein the metal-based material is independently chosen from silver, tin, lead, silver-copper, nickel or combinations of two or more thereof and (ii) an agent that is reactive with the bulk graphene material to form a carbide wherein the agent is chosen from titanium, zirconium, chromium, hafnium, aluminum, tantalum, iron, silicon, or a combination of two or more thereof, wherein the first and second thermal bond layers are each a single layer and wherein the first and second thermal bond layers independently have a thermal conductivity of about 20 W/m-K or greater, and a melting temperature less than the melting temperature of the substrates and less than the melting temperature of the bulk graphene material.
2. The thermal management assembly of claim 1 , wherein the bulk graphene material comprises at least 3000 graphene layers, the graphene layers being parallel to each other at an angle of at most 1 degree per mm in thickness.
3. The thermal management assembly of claim 2 , wherein the bulk graphene material exhibits an in-plane thermal conductivity at least of 1000 W/m-K.
4. The thermal management assembly of claim 2 , wherein the bulk graphene material exhibits an in-plane thermal conductivity from about 1000 W/m-K to about 1800 W/m-K.
5. The thermal management assembly of claim 1 , wherein the thermal bond layers have a composition different from the composition of the first substrate and the second substrate.
6. The thermal management assembly of claim 1 , wherein the first substrate and the second substrate independently comprise a metal or a ceramic material.
7. The thermal management assembly of claim 1 , wherein the first substrate and the second substrate independently comprise copper, aluminum, tungsten, molybdenum, nickel, iron, tin, silver, gold, beryllium, or alloys of two or more thereof.
8. The thermal management assembly of claim 1 , wherein the first substrate and the second substrate independently comprise silicon nitride, silicon carbide, aluminum nitride, aluminum oxide, beryllium oxide, boron nitride, or a combination of two or more thereof.
9. The thermal management assembly of claim 1 , wherein the first substrate comprises copper, aluminum, tungsten, molybdenum, nickel, iron, tin, silver, gold, beryllium, or alloys of two or more thereof, and the second substrate comprises silicon nitride, silicon carbide, aluminum nitride, aluminum oxide, beryllium oxide, boron nitride, or a combination of two or more thereof.
10. The thermal management assembly of claim 1 , wherein the bulk graphene material has a thickness from about 25% to about 95% of the total thickness of the thermal management assembly.
11. The thermal management assembly of claim 1 , wherein the bulk graphene material has a thickness from about 35% to about 90% of the total thickness of the thermal management assembly.
12. The thermal management assembly of claim 1 , wherein the bulk graphene material comprises at least 3000 of graphene layers, and the bulk graphene material is disposed in the assembly such that the graphene layers are oriented perpendicular to the first and second substrates.
13. The thermal management assembly of claim 12 , having a through-plane thermal conductivity of from about 200 W/m-K to about 1200 W/m-K.
14. The thermal management assembly of claim 1 , wherein the thermal bond has a thermal resistance of less than 10×10-6 K-m2/W.
15. The thermal management assembly of claim 1 , wherein the thermal bond has a thermal resistance of less than 5×10-6 K-m2/W.
16. The thermal management assembly of claim 1 , wherein the thermal bond has a thermal resistance of less than 1×10-6 K-m2/W.
17. The thermal management assembly of claim 1 , wherein the thermal bond has a thermal resistance of less than 0.5×10-6 K-m2/W.
18. The thermal management assembly of claim 1 , wherein the thermal bond has a thermal resistance of less than 0.1×10-6 K-m2/W.
19. An apparatus comprising a heat generating component and the thermal management assembly of claim 1 disposed adjacent the heat generating component such that heat from the heat generating component can be transferred through the thermal management assembly.