Heat transport structure and manufacturing method thereof
In order to provide a thermal transport structure excellent in bendability, heat dissipation property, and lightweight property and also a thermal transport structure having a high reliability against vibrations and an excellent heat transport performance, used is a thermal transport structure ( 5, 201 ) including stacked graphite sheets ( 1, 213 ). This thermal transport structure ( 5, 201 ) includes a fixing portion ( 10, 202, 301 ) in which the stacked graphite sheets ( 1, 213 ) are fixed to each other; and a thermally conductive portion ( 11, 203 ) in which the stacked graphite sheets ( 1, 213 ) are not fixed to each other.
1. A thermal transport structure comprising:
at least two fixing portions; and
a thermally conductive portion between the fixing portions,
wherein the thermal transport structure has a resilience against bending of not more than 40 N/cm in a case where a distance between the fixing portions is shortened and the thermally conductive portion is compressed by 10% in length,
wherein the fixing portions and the thermally conductive portion are provided with at least two thermally conductive sheets,
wherein the thermally conductive sheets each is a graphite sheet or a graphite composite sheet obtained by covering, by a covering layer, at least a part of (i) a surface and (ii) an edge of the graphite sheet, and
wherein the graphite sheet has a thermal conductivity in a plane direction of not less than 900 W/m·K.
2. The thermal transport structure of claim 1 , wherein:
the graphite sheet has a thermal conductivity in a plane direction of not less than 1,000 W/m·K.
3. The thermal transport structure of claim 1 , wherein:
in each of the fixing portions, the thermally conductive sheets are kept in a state in which the thermally conductive sheets are bonded to each other via a bonding layer which comprises at least one selected from the group consisting of a thermosetting resin, a thermoplastic resin, and a sticky resin.
4. The thermal transport structure of claim 1 , wherein:
the covering layer comprises at least one selected from the group consisting of a thermosetting resin, a thermoplastic resin, and a sticky resin; and
in each of the fixing portions, the covering layer is subjected to thermal curing or thermal welding, or made adhesive, so that the thermally conductive sheets are kept in a state in which the thermally conductive sheets are bonded to each other.
5. The thermal transport structure of claim 1 , further comprising:
a flat plate provided on at least one side of at least one fixing portion,
wherein each fixing portion and the flat plate have through holes, respectively, and
wherein each fixing portion and the flat plate are fixed by a bolt inserted through the through holes such that the thermally conductive sheets are kept in a state in which the thermally conductive sheets are in contact with each other.
6. The thermal transport structure of claim 1 , wherein:
in each of the fixing portions, the thermally conductive sheets are kept in a state in which the thermally conductive sheets are in contact with each other or bonded to each other; and
in the thermally conductive portion, the thermally conductive sheets are at least partially out of contact with each other or at least partially not bonded to each other.