Metal composite structure and method for producing same

A metal composite structure comprising:

• a thin steel sheet;
• a low-specific-gravity sheet material having a lower specific gravity than the thin steel sheet and a lower strength than the thin steel sheet;
• and
• an adhesive layer bonding the thin steel sheet and the low-specific-gravity sheet material and having a lower strength than the thin steel sheet and the low-specific-gravity sheet material,
• wherein a sheet thickness of the thin steel sheet and a sheet thickness of the low-specific-gravity sheet material are set so as to satisfy the following Equation (1) representing a bending rigidity D of the metal composite structure and Inequality (2), the bending rigidity D being set in advance:
• D
• =
• b
• ⁢
• E
• 1
• 3
• ⁢
• (
• 1
• -
• v
• 1
• 2
• )
• ⁢
• {
• (
• h
• 1
• +
• h
• 3
• -
• h
• 0
• )
• 3
• -
• (
• h
• 3
• -
• h
• 0
• )
• 3
• }
• +
• b
• ⁢
• E
• 2
• 3
• ⁢
• (
• 1
• -
• v
• 2
• 2
• )
• ⁢
• {
• (
• h
• 2
• +
• h
• 0
• )
• 3
• -
• h
• 0
• 3
• }
• (
• 1
• )
• h
• 1
• <
• h
• 2
• (
• 2
• )
• wherein in Equation (1),
• b is a width of the metal composite structure,
• E1 is a longitudinal elastic modulus of the thin steel sheet,
• E2 is a longitudinal elastic modulus of the low-specific-gravity sheet material,
• v1 is a Poisson's ratio of the thin steel sheet,
• v2 is a Poisson's ratio of the low-specific-gravity sheet material,
• h1 is the sheet thickness of the thin steel sheet,
• h2 is the sheet thickness of the low-specific-gravity sheet material,
• h3 is a thickness of the adhesive layer, and
• h0 is a distance of a neutral axis of the metal composite structure from a joint interface between the adhesive layer and the low-specific-gravity sheet material, the distance measured from the joint interface between the low-specific-gravity sheet material and the adhesive layer towards the thin steel sheet and satisfying 0≤h0≤h3, and
• wherein in Inequality (2), h1 and h2 have the same meaning as in Equation (1).