ABAQUS/Explicit uses a central difference rule to integrate the kinematics explicitly through time.

The explicit method requires many small time increments. Since there are no simultaneous equations to solve, each increment is inexpensive.

The explicit method has great cost savings over the implicit method as the model size increases.

The stability limit is the maximum time increment that can be used to advance the kinematic state and still remain accurate.

ABAQUS/Explicit automatically controls the time increment size throughout the analysis to maintain stability.

As the material stiffness increases, the stability limit decreases; as the material density increases, the stability limit increases.

For a mesh with a single material, the stability limit is roughly proportional to the smallest element dimension.

In some situations an ABAQUS/Explicit analysis may become unstable. The example problems in this chapter describe how to recognize and rectify instabilities.