litteälevy

Litteälevy, written as litteä levy in Finnish, is a term used in engineering, materials science and architecture to refer to a flat, planar solid with uniform thickness. The word combines litteä, meaning flat, with levy, meaning plate or sheet. In English, the equivalent concept is a flat plate.

Geometrically, a litteälevy is characterized by two large in‑plane dimensions and a much smaller thickness. Shapes commonly encountered are rectangular, circular or square plates. In many applications, the thickness is small enough for plate theories to be used, such as Kirchhoff–Love plate theory for bending, which treats the plate as a thin, flexible shell.

Materials used for litteälevy vary widely and include metals (steel, aluminum, copper), ceramics, polymers and composite materials. Manufacturing methods include sheet metal rolling, extrusion, casting followed by machining, or additive manufacturing, depending on the material and required tolerances. Surface finishing, coating, and heat treatment are common processing steps to achieve desired properties such as corrosion resistance or hardness.

Applications of litteälevy are broad. In construction and machinery, flat plates serve as structural components, brackets, or housings. In heat transfer, plate heat exchangers and heat sinks use flat plates to maximize surface area. In renewable energy, flat-plate solar collectors use flat plates to absorb sunlight. In electronics and acoustics, flat plates act as heat spreaders or reflectors. Architectural uses include cladding and decorative panels.

See also: plate (solid mechanics), sheet metal, plate heat exchanger, flat-plate solar collector.