Elasticity is the physical property of a body of returning to its initial shape after the load is removed.
The body is perfectly elastic if it returns to an identical shape.
It is partially elastic if the deformation produced by external forces does not completely disappear when the forces are removed.
Experience shows that if a certain deformation limit, and therefore a certain stress, (called the elastic limit) is not exceeded,, materials such as steel and metal alloys can generally be considered to be perfectly elastic.
For composite materials with a polymer matrix, they can be considered, in a first approximation, to be perfectly elastic, but in fact, certain relaxation and creep phenomena appear (especially when there is draping in several directions, which is usually the case).