The present invention provides a high Al-content steel sheet having an excellent workability and a method of production of the same at a low cost by mass production, a high Al-content metal foil and a method of production of the same, and a metal substrate using a high Al-content metal foil, that is, a high Al-content steel sheet having an Al content of 6.5 mass % to 10 mass %, the high Al-content steel sheet characterized by having one or both of a {222} plane integration of an -Fe crystal with respect to the surface of the steel sheet of 60% to 95% or a {200} plane integration of 0.01% to 15% and a method of production of the same, a high Al-content metal foil and a method of production of the same, and a metal substrate using a high Al-content metal foil.

A sandwich structure employs a core sheet including alternating peaks and valleys therein, and at least one outer face sheet including grooves or ribs therein. In another aspect, a sandwich structure includes at least one core and at least one adhesively bonded outer face sheet including elongated grooves or ribs formed therein. Yet another aspect of a sandwich structure has raised ridges bridging between adjacent peaks in a core sheet in one direction but not in a perpendicular direction, which synergistically interface, engage or contact with grooves or ribs formed in an outer face sheet.

A spacer structure for a sandwich construction, formed from a material web which is provided with a plurality of cuts and which has a material web plane as a first plane, wherein, by forming the material web, at least one support platform is formed in portions which is spaced at a distance from the first plane and is arranged in a second plane. Spacing elements run along a direction of extent (E) from the first plane into the second plane in the transition zone from the first plane into the second plane and thus the spacing elements space the first plane apart from the support platform, the spacing elements having a twist about the direction of extent thereof along the direction of extent thereof (E), the twist being formed by the shaping of the material web being performed as bending.