Anisotropic graphite, anisotropic graphite composite, and method for producing same
Anisotropic graphite and an anisotropic graphite composite are provided, each having excellent heat transmission performance and excellent long-term reliability as a heat transmitting element, and a production method for the anisotropic graphite composite. A face of anisotropic graphite which face is perpendicular to crystal orientation planes of graphite layers of the anisotropic graphite may be subjected to surface treatment so as to obtain anisotropic graphite having a specific surface roughness. An anisotropic graphite composite may include anisotropic graphite having an interface that has a specific interface roughness; a titanium-containing metal layer; and an inorganic material layer.
1. An anisotropic graphite composite comprising:
(a) anisotropic graphite;
(b) a titanium-containing metal layer; and
(c) an inorganic material layer,
the (a) anisotropic graphite having graphite layers whose respective crystal orientation planes are parallel to an X-Z plane, given an X axis, a Y axis orthogonal to the X axis, and a Z axis perpendicular to an X-Y plane,
the anisotropic graphite (a) having a length in a direction parallel to the X axis of not less than 4 mm and not more than 300 mm,
the anisotropic graphite (a) having a length in a direction parallel to the Y axis of not less than 4 mm and not more than 300 mm,
the anisotropic graphite (a) having a thickness in a Z axis direction of not less than 0.5 mm and not more than 5.0 mm,
the anisotropic graphite (a), the titanium-containing metal layer (b), and the inorganic material layer (c) being stacked in this order in the Z axis direction and joined to each other,
an interface of the anisotropic graphite (a), at which the anisotropic graphite (a) is joined to the titanium-containing metal layer (b), having an interface roughness of not less than 2 μm and not more than 7 μm,
an interface of the inorganic material layer (c), at which the inorganic material layer (c) is joined to the titanium-containing metal layer (b), having an interface roughness of not less than 3 μm and not more than 10 μm.
2. The anisotropic graphite composite according to claim 1 , wherein the interface of the anisotropic graphite (a) at which the anisotropic graphite (a) is joined to the titanium-containing metal layer (b) has an interface roughness of not less than 2 μm and not more than 4 μm.
3. The anisotropic graphite composite according to claim 1 , wherein the titanium-containing metal layer (b) has a thickness of not less than 20 μm and not more than 40 μm.
4. The anisotropic graphite composite according to claim 1 , wherein the titanium-containing metal layer (b) has a titanium content of not less than 0.1 weight % and not more than 2.0 weight %.
5. The anisotropic graphite composite according to claim 1 , wherein an interface of the inorganic material layer (c) at which the inorganic material layer (c) is joined to the titanium-containing metal layer (b) has an interface roughness of not less than 2 μm and not more than 8 μm.
6. The anisotropic graphite composite according to claim 1 , wherein the interface of the inorganic material layer (c), at which the inorganic material layer (c) is joined to the titanium-containing metal layer (b), has an interface roughness of not less than 3 μm and not more than 5 μm.