| 摘要 |
PROBLEM TO BE SOLVED: To increase the thermal conductivity of the composite material by controlling the asepect ractio of particles essentially consisting of silicon carbide to the value above the specified one and allowing the thermal conductivity in the 1st direction and that in the 2nd direction orthogonal to the 1st direction to satisfy specified relation. SOLUTION: This material is the one in which the aspect ratio of silicon carbide particles is controlled to >1, and there is anisotropy in thermal conductivity. Namely, the relation of 0.7Kx<=Ky<=0.9Kx is valid between the thermal conductivity Kx in the 1st direction of the material and the thermal conductivity Ky in the 2nd direction orthogonal to the 1st direction. In the case a planar radiating substrate is formed by using this material, ordinarily, the 1st direction is applied as the main plane direction, and the 2nd direction is applied as the thickness direction. In the case of being increasing the thermal conductivity in the main face direction, in the producing process of the material, the main planes of the powder particles are orientated to the main plane of the substrate as much as possible. The degree of the anisotropy is remarkable, mainly, as the aspect ratio is made higher, but, it is influenced also by the amt. of the silicon carbide particles, and the amt. is preferably controlled to 50 to 80 wt.%. |
