Jfe Steel Corporation

Jfe Techno-research Corporation

Akihide Yoshitake

Yuji Yamasaki

Rinsei Ikeda

Kentaro Sato

Yoshikiyo Tamai

Takanobu Saito

Muneo Matsushita

Takashi Iwama

Mitsuaki Uesugi

This indirect spot welding is for welding members including at least two overlapping steel sheets that have a ferrite phase as a main phase by holding a welding electrode () against a steel sheet () from one side while applying pressure with the electrode (), attaching a feeding point () to a steel sheet () at the other side at a location remote from the electrode (), and allowing current to flow between the electrode () and the feeding point (). This welding includes contacting magnetic rigid bodies (--) to a peripheral area of the electrode () from the one side against which the electrode () is held and securing an overlapping region in the peripheral area of the electrode () by a magnetic force produced by the rigid bodies (--), thereby obtaining a weld having fully satisfactory strength, regardless of the rigidity of the members.

Indirect spot welding method

A press forming method for a metal sheet uses dies, a surface roughness of which is an arithmetical mean roughness Ra of 7.5 &#x3bc;m or smaller, which are used as a punch, an upper die, and a blank holder. Fluid with a kinematic viscosity of 500 mm/s or lower is supplied to a space between a metal sheet and the blank holder, a space between the metal sheet and the punch, and a space between the metal sheet and the upper die. A die is detached from a workpiece in the middle of forming, and resuming the forming.

Press forming method for metal sheet and frame part for automotive body manufactured thereby

A surface-distortion measuring device and a surface-distortion measuring method can quantitatively, rapidly, and highly accurately measure and evaluate surface-distortion distribution at all of observable points on a specular or semi-specular surface of a measurement target. The device includes pattern displaying meanscapable of switching and displaying a plurality of kinds of light-and-shade patterns, capturing meansfor capturing mirror images, reflected in the specular or semi-specular surface of a measurement target, of the plurality of light-and-shade patterns displayed on the pattern displaying means, and surface-distortion distribution calculating meansfor performing image processing on the captured mirror images of the plurality of light-and-shade patterns to calculate surface-distortion distribution of the measurement-target surface.

Surface-distortion measuring device and method

Growing community of inventors

Toyko, Japan

Akihide Yoshitake