Patent attributes
Provided is a method for manufacturing a liquid cooling jacket including a jacket body and a sealing body joined to the jacket body. The method includes steps of: preparing; placing; first primary joining with a rotary tool; and second primary joining with the rotary tool. A rotary tool includes a base end pin and a distal end pin. The distal end pin includes a flat surface and a protrusion extending from the flat surface. In the first primary joining and the second primary joining, friction stirring is performed in a state where a front surface of the sealing body is brought in contact with an outer peripheral surface of the base end pin, the sealing body is brought in contact with the flat surface of the distal end pin, and the jacket body is brought in contact with the protrusion.
