Structure around through-hole in metal sheet, blank, and automotive part

A structure around a through-hole formed in a metal sheet, the structure comprising:

• a flat portion;
• and a processed portion rising from the flat portion to one side in a thickness direction of the flat portion and having the through-hole formed in a center,
• wherein the flat portion includes a first flat surface surrounding periphery of the processed portion on the one side of the flat portion,
• the processed portion includes a wall surface extending in the thickness direction and constitutes an inner wall of the through-hole, an annular second flat surface extending in a direction intersecting the thickness direction from an edge on the one side of the wall surface at an inner side of the first flat surface when viewed from the thickness direction and on the one side of the first flat surface in the thickness direction, and an inclined surface connecting an outer edge of the second flat surface and an inner edge of the first flat surface, and inclined with respect to the thickness direction,
• when viewed from the thickness direction, the through-hole includes a curved portion curved in an arc so as to be convex toward an outside of the through-hole,
• in a cross section of the processed portion that is parallel to the thickness direction and passes through a center of the through-hole and the curved portion, following formulas (i) and (ii) are satisfied:
• 1.
• ≤
• W
• ≤
• -
• 3.8314
• ×
• (
• R
• /
• t
• )
• +
• 11.47
• ≤
• 5.
• (
• i
• )
• 0.1
• ≤
• H
• ≤
• -
• 0.6604
• ×
• (
• R
• /
• t
• )
• +
• 2.0489
• ≤
• 1.
• (
• ii
• )
• where, in the formulas (i) and (ii), W is a length (mm) of the inclined surface in a direction orthogonal to the thickness direction, R is a curvature radius (mm) of a portion corresponding to the cross section of the curved portion, t is a thickness (mm) of the metal sheet, and H is a distance (mm) between the first flat surface and the second flat surface in the thickness direction.