New features in Z-mat 8.0.3

Many comprehensive developments were added to the 8.0.3 version of Z-set, including many new capabilities for Z-mat users. A summary of some of the additions follows.

• Speed improvements Many speed improvements have been made both algorithmically and in program optimization. Running a small problem in Z-mat with simple materials model which exist in ABAQUS typically consumes more CPU than the native material models (usually a factor of 1.6). This is due to extra data exchange which must be done, and very general program implementation.
• ABAQUS/Explicit There is now an interface with ABAQUS/Explicit.
• Ansys interface The ANSYS interface was completed this year, and performs very well. In particular with ANSYS 5.7 new post processing capabilities have been added so the state variables can be visualized.
• External variable storage Z-mat can now use an external database file for the state variables. This feature allows any number of state variables to be used with Z-mat breaking the barriers presented by different codes (e.g. Cosmos and ABAQUS.
• Cycle skipping with ABAQUS A special module has been developed to control ABAQUS and provide cyclic based extrapolation to greatly speed up fatigue analysis.
• More automatic time stepping integration A local-level sub-stepping is available for implicit integration allowing highly non-linear materials to pass without causing the global problem time step to reduce.
• Perturbation derivatives Finite difference analysis is now available for the local integration Jacobian and the material tangent. These methods are useful for highly complex models and user development.
• Ability to run Fortran UMATs Z-mat now has a "wrapper" behavior which can be used to run Fortran UMAT code within the Z-mat platform. This is primarily useful for using the Simulation/Optimization programs directly on those existing programs.

• Cast iron material
• Non-quadratic yields
• Dynamic strain aging
• More kinematic hardening

New features in Z-mat 8.3

• Greatly expanded documentation
• User elements
• Improved performance with explicit solvers including parallel
• LS Dyna interface

• General multi-mat
• Finite strain viscoelasticity with damage
• Porous plastic with kinematic hardening
• Multi-surface porous plastic

New features in Z-mat 8.4

• Continued expansion of the documentation
• Improvements of the graphical user interface, Zmaster, to include a GUI for Z-sim