Ply Angle

Laminates are generally stacked with plies of different orientations. You stack laminates with plies of different orientations when you need to optimize load-carrying capacity in different directions. Such stacking is necessary as laminates are subjected to complex external loading conditions

Unidirectional laminates (same material orientation across different plies) are usually suitable for carrying loads in only one direction. They are usually weak in the transverse direction to ply orientation.

When you select the row of a ply in the Composite shell plies table, the program highlights that ply angle on the geometry by means of stripes. The ply orientation direction for each lamina, which is the X direction for material properties is highlighted on the geometry. The Y direction is transverse to fiber direction (on surface) and the Z direction is normal to the ply surface. The images show the X, Y and Z directions for ply angles 0 degrees and 60 degrees.

Ply angle: 0 degrees Ply angle: 60 degrees

A composite triad is shown at the center of face. The triad has four arrows:

Shows the 0 degree ply orientation. The red arrow is aligned with the surface stripes.
Shows the 90 degree ply orientation. The green arrow is aligned normal to the surface stripes.
The blue arrow is normal to the surface. Mirror orientation flips the blue arrow direction.
Shows the ply orientation direction.