Isogrid

An isogrid is a plate (or face sheet) with triangular integral stiffening ribs (often called stringers). The stiffeners of an isogrid are generally machined from a single sheet of material with a milling machine, though below 0.040 in. (1.0 millimeter) thickness chemical milling processes must be used. The triangular pattern is very efficient because triangular trusses are very efficient structures. The term isogrid is used because the structure acts like an isotropic material, with equal properties measured in any direction, and grid, referring to the sheet and stiffeners structure.