| 摘要 |
A shaped steel wherein a T-shaped joint part, which is formed by pressing an end of a web material comprising a steel plate perpendicularly against a flange material comprising a steel plate, is welded/joined by irradiation with one pass of laser light from one side. When the surface fusing width of the web material (on the laser light irradiation side) is a, the rear surface fusing width of the web material (on the side without laser light irradiation) is b, the maximum penetration depth of the flange material in the plate pressure direction is c, the surface fusing width of the flange material (on the laser light irradiation side) is d, the rear surface fusing width of the flange material (on the side without laser light irradiation) is e, and the thickness of the web material is Tw, the equations a > 0 mm, b > 0 mm, c = 0.14Tw, d = 0 mm, and e = 0 mm are satisfied for the shape of the welded portion in a cross-section perpendicular to the length direction of the shaped steel. Furthermore, when both the flange material and the web material comprise a galvanized steel plate, preferably the equations a > 0 mm, b > 0 mm, c = 0.14Tw, d = 0 mm, e = 0 mm, a+d = 2 mm, and b+e = 2 mm are satisfied. |
