| 摘要 |
A base 1 having a recess 2, and a cover 3 to be fitted into the recess 2 and to close an opening of the recess 2 are prepared. A stepped portion 4 is formed on the inner circumferential surface of the recess 2 at an intermediate depth for allowing a peripheral portion of the cover 3 to rest thereon. A cylindrical holder portion 5 having a cooling-medium accommodation recess 6 is formed integrally with the outer surface of the cover 3. The cover 3 is fitted into the recess 2 and placed on the stepped portion 4. A cooling medium for removing latent heat is placed in the cooling-medium accommodation recess 6 of the holder portion 5 of the cover 3. A probe 9 of a friction-stir-welding tool is plunged from outside into a peripheral portion of the base 1 around an opening of the recess 2 and into a peripheral portion of the cover 3. Then, during rotation of the probe 9, the base 1 and the cover 3, and the probe 9 are caused to undergo relative movement, thereby friction-stir-welding the base 1 and the cover 3 together. This method of manufacturing a hollow body can be carried out at low cost. |
