公开(公告)号：US11992892B2

公开(公告)日：2024-05-28

申请号：US16967193

申请日：2019-02-05

Applicant: JFE Steel Corporation

Inventor： Reiko Endo ,  Muneo Matsushita ,  Koichi Taniguchi ,  Hiroshi Matsuda ,  Rinsei Ikeda

IPC: B23K11/11 ,  B23K11/16 ,  B23K11/24 ,  B23K101/00 ,  B23K101/18 ,  B23K103/04 ,  C21D6/00 ,  C21D9/50 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54

CPC classification number: B23K11/115 ,  B23K11/16 ,  B23K11/24 ,  C21D6/004 ,  C21D9/50 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54 ,  B23K2101/006 ,  B23K2101/18 ,  B23K2103/04

Abstract: The present invention provides a resistance spot welding method. A resistance spot welding method according to the present invention in which a sheet combination of two or more overlapping steel sheets is sandwiched between a pair of electrodes and joined together by applying current while applying pressure, the method including a main current application step in which current application is performed with a current Iw (kA), and subsequently, a post-tempering heat treatment step in which after cooling is performed for a cooling time tct (ms) shown in formula (1) below, current application is performed with a current It (kA) shown in formula (2) below for a current application time tt (ms) shown in formula (3) below: 800≤tct . . . formula (1), 0.5×Iw≤It≤Iw . . . formula (2), and 500≤tt . . . formula (3).

公开(公告)号：US11498150B2

公开(公告)日：2022-11-15

申请号：US16645789

申请日：2018-08-14

Applicant: JFE STEEL CORPORATION

Inventor： Koichi Taniguchi ,  Reiko Endo ,  Katsutoshi Takashima ,  Hiroshi Matsuda ,  Rinsei Ikeda

IPC: B23K11/16 ,  B23K103/08 ,  B23K103/04 ,  B23K11/11

Abstract: Main current passage and subsequent current passage are performed, with a cooling time of 0.01 s or more being provided between the main current passage and the subsequent current passage. Ip/I which is a ratio of a current value of the subsequent current passage to a current value of the main current passage is controlled to satisfy a predetermined relationship depending on a constant A defined by Mn content and P content of a steel sheet as a part to be welded, in relation to a welding time Tp of the subsequent current passage, a cooling time T, and the constant A.

公开(公告)号：US20210362266A1

公开(公告)日：2021-11-25

申请号：US16967193

申请日：2019-02-05

Applicant: JFE Steel Corporation

Inventor： Reiko Endo ,  Muneo Matsushita ,  Koichi Taniguchi ,  Hiroshi Matsuda ,  Rinsei Ikeda

IPC: B23K11/11 ,  B23K11/16 ,  B23K11/24 ,  C21D9/50 ,  C22C38/54 ,  C22C38/50 ,  C22C38/48 ,  C22C38/46 ,  C22C38/44 ,  C22C38/42 ,  C22C38/06 ,  C21D6/00 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04

Abstract: The present invention provides a resistance spot welding method. A resistance spot welding method according to the present invention in which a sheet combination of two or more overlapping steel sheets is sandwiched between a pair of electrodes and joined together by applying current while applying pressure, the method including a main current application step in which current application is performed with a current Iw (kA), and subsequently, a post-tempering heat treatment step in which after cooling is performed for a cooling time tct (ms) shown in formula (1) below, current application is performed with a current It (kA) shown in formula (2) below for a current application time tt (ms) shown in formula (3) below: 800≤tct . . . formula (1), 0.5×Iw≤It≤Iw . . . formula (2), and 500≤tt . . . formula (3).