公开(公告)号：US20220009022A1

公开(公告)日：2022-01-13

申请号：US17413680

申请日：2019-12-13

Applicant: NHK Spring Co., Ltd.

Inventor： Toshihiko Hanamachi ,  Daisuke Fujino ,  Masaru Takimoto ,  Yoshihito Araki ,  Masahiro Fujii

IPC: B23K20/02 ,  B23K20/00 ,  B23K20/233

Abstract: A joining method of joins a main body and a cover, the main body being a flat plate and made of aluminum or an aluminum alloy and including a passage through which a medium for promoting heat exchange is circulated, and the cover being a flat plate and made of aluminum or an aluminum alloy and configured to cover the passage of the main body. The method includes: a covering step of covering the main body with the cover; and a diffusion bonding step of joining the main body and the cover by diffusion bonding under a condition in which a joining temperature is 500° C. or higher and 640° C. or lower, and a joining surface pressure is 0.7 MPa or higher. Each of a joining surface of the main body and a joining surface of the cover has a flatness of 0.2 or less.