Heat dissipation member
A substantially rectangular flat heat dissipation member includes: a composite portion where silicon carbide having voids is impregnated with metal; and a metal portion that is different from the composite portion. Here, a proportion of a volume of the metal portion to a total volume of the heat dissipation member is 2.9% or higher and 12% or lower. In addition, when a length of a diagonal line of the rectangular flat heat dissipation member is represented by L, in a top view where one main surface of the heat dissipation member is a top surface, 40% or higher of a total volume of the metal portion is present in a region D within a distance of L/6 from an apex of any one of four corners of the heat dissipation member. Further, a hole penetrates the metal portion in the region D.
1. A heat dissipation member that is substantially rectangular flat, the heat dissipation member comprising:
a composite portion where silicon carbide having voids is impregnated with metal; and
a metal portion that is different from the composite portion,
a proportion of a volume of the metal portion to a total volume of the heat dissipation member is 2.9% or higher and 12% or lower,
when a length of a diagonal line of the heat dissipation member is represented by L, in a top view where one main surface of the heat dissipation member is a top surface, 40% or higher of a total volume of the metal portion is present in a region D within a distance of L/6 from an apex of any one of four corners of the heat dissipation member, and
a hole that penetrates the metal portion in the region D is provided.
2. The heat dissipation member according to claim 1 ,
wherein a thickness of the metal portion present in the region D is substantially the same as a thickness of the composite portion.
3. The heat dissipation member according to claim 1 ,
wherein when the volume of the metal portion present in the region D is represented by V metal and a volume of the hole is represented by V hole , a value of V hole /(V metal +V hole ) is 0.60 or lower.
4. The heat dissipation member according to claim 1 ,
wherein when a radius of the hole is represented by r in the top view of the heat dissipation member where one main surface of the heat dissipation member is a top surface, the composite portion is not present in a region within a distance of 1.3 r from a center of the hole.
5. The heat dissipation member according to claim 1 ,
wherein in the top view of the heat dissipation member where one main surface of the heat dissipation member is a top surface, the hole is not present in a region within a distance of L/40 from apexes of the four corners of the heat dissipation member.
6. The heat dissipation member according to claim 1 ,
wherein a part of the metal portion is continuously provided in a peripheral portion of the heat dissipation member.
7. The heat dissipation member according to claim 1 ,
wherein in the top view of the heat dissipation member where one main surface of the heat dissipation member is a top surface,
the metal portion includes a first metal portion that includes at least a part of a peripheral portion of the heat dissipation member and a second metal portion that is not in contact with the peripheral portion of the heat dissipation member and the first metal portion,
the second metal portion is present at a distance of L/55 to L/5 from a closest apex in the heat dissipation member, and
the hole penetrates the second metal portion.
8. The heat dissipation member according to claim 1 ,
wherein the metal portion includes an inorganic fiber containing alumina or silica as a main component.
9. The heat dissipation member according to claim 1 ,
wherein a relative density of the silicon carbide is 55% or higher and 75% or lower.
10. The heat dissipation member according to claim 1 ,
wherein the metal with which the composite portion is impregnated and metal contained in the metal portion are the same.