Nippon Steel Corporation

Sho Matsui

Seiji Furusako

Masahiro Saito

Hiroyuki Kawata

Kunio Hayashi

Shinji Kodama

Yasunobu Miyazaki

Fuminori Watanabe

Chisato Wakabayashi

Katsunari Norita

Yutaka Mikazuki

Chisato Yoshinaga

Kyohei Miyake

Takashi Oke

According to the present invention, provided are a joint structure () which joins a plurality of overlapped steel members () using a connecting element () having a shaft portion (), the joint structure including: a first steel member (); and one or more of second steel members () overlapping the first steel member (), in which the shaft portion () of the connecting element () is penetrated through the second steel member (), and the shaft portion () of the connecting element () and the second steel member () are joined by friction welding, and the shaft portion () and the first steel member () are joined by friction welding, and a joining method for obtaining the joint structure.

Joint structure and joining method

Art for spot welding able to suppress penetration of hydrogen, one of the factors behind delayed fracture, at the time of spot welding, that is, a spot welding method in which at one or both of the surfaces of the steel sheets becoming the facing surfaces of the overlaid steel sheets, a location where the steel sheets contact each other to form a contact part at the time of initial squeezing of the spot welding is worked in advance to form a plurality of lines running through the contact part and connected to the outside of the contact part and the spot welding is performed at the location of the contact part and also a steel sheet in which the plurality of lines are formed in advance at the location becoming a contact part when steel sheets contact each other at the time of initial squeezing in the spot welding.

Method of manufacture of spot welded joint, steel sheet for spot welding use, and steel sheet member for spot welding use

A spot welding method able to simply prevent liquid metal embrittlement cracks in spot welding of plated steel sheets, comprising, before spot welding, removing the plating at least in a zone including the inside of a circle centered at a scheduled location where the center of the nugget is formed and having an outer circumference of the inside of the outer edge of a weld affected zone or a zone at the mated surfaces of the steel sheets to be welded at the inside of a circle sharing a center of a scheduled location becoming the center of the nugget formed at the mated surfaces of the steel sheets and having an outer circumference of the inside of the outer edge of a weld affected zone.

Method of spot welding

Growing community of inventors

Tokyo, Japan

Sho Matsui