Balanced laminate

A laminate whose ply orientations and materials mirror each other about the mid-plane. Symmetry prevents coupling between in-plane loads and bending, so the laminate remains flat after cure instead of warping.

The specified order and orientation of the plies through the thickness of a laminate, usually written as a shorthand code of ply angles. It governs the laminate's stiffness, strength and coupling behaviour, and is fixed on the drawing as part of the laminate schedule.

A laminate with equal numbers of plies in three or more equally spaced orientations, giving in-plane stiffness that is effectively the same in every direction. It is the standard conservative layup where load directions are uncertain or vary in service.