Use MatEditor to generate OpenRadioss material data files


November 26, 2022

OpenRadioss is an open-source enterprise-grade explicit dynamics analysis software. Due to its powerful features and long history, it gains a lot of attention from the communities when this open-source project was announced in September 2022. However, as a console solver, OpenRadioss does not have an easy-to-use dedicated GUI front-end program yet. For new users, there is a relatively large learning curve. Therefore an easy-to-use OpenRadioss GUI software is of great significance for the OpenRadioss project, users with simulation needs, and even the entire simulation community.


MatEditor is a free material editing software released by WelSim in September 2019 (see “A Free Material Editing Tool MatEditor”). Because of its rich features and easy-to-use interface, it has been recognized by many users. In addition to conventional material property editing, MatEditor added the test data curve fitting features (see “Hyperelastic Material Model and Its Curve Fitting”). Recently, MatEditor supports OpenRadioss’ material format text file generation. Undoubtedly, MatEditor is the best free material editing software that supports the OpenRadioss format, and the related features are introduced as follows.


Supported Unit Systems

At present, MatEditor supports eight types of unit systems commonly used in engineering simulation, which are as follows.

  • Metric kg-m-s
  • Metric g-cm-s
  • Metrickg-mm-s
  • Metric tonne-mm-s
  • Metric decatonne-mm-s
  • Metric kg-um-s
  • US Customary lbm-ft-s
  • US Customary lbm-in-s
  • Metric g-cm-us

The user can change the system unit system at any time, and the generated OpenRadioss material file will also be based on the current unit system, and the unit conversion will be performed automatically during exporting.


In engineering analysis, a large number of units are involved. Currently, MatEditor already supports 81 different quantities. The figure below shows the commonly used pressure unit in structural analysis.


Save and Resume

MatEditor supports data persistence. Users can save all currently created material nodes as wsmat files. Files can be read on other machines for data sharing. The wsmat file is an ASCII file in XML format, which not only takes into account the performance of data reading and loading but also supports human reading.


An example wsmat file is shown in the figure. Supports reading and writing of multiple materials.


Tabular Data Input

Material properties, in addition to the usual constants. A large amount of experimental data, such as strain-stress curves, also needs to be input. MatEditor not only supports conventional table input, but also supports multi-dimensional tables based on strain rate, temperature, and frequency. While inputting table data, you can observe the shape of the input curve through the chart window. Data input not only supports manual input cell by cell, but also supports copy and paste, and reading from external files.


Export OpenRadioss Material Files

It is very easy and straightforward to export the OpenRadioss file (.rad) file using MatEditor. The toolbar and menu bar of MatEditor provide relevant buttons. When the material editing is completed, click them to proceed with the output.


An example of the output rad file is as follows. Units and all material properties are defined in the file. Note that MatEditor supports exporting multiple materials in one single rad file.


Suppress Specified Materials

When editing materials, some material properties will not be used after being added. At this time, you can simply suppress the material properties by selecting the boolean dropdown. The suppressed material properties will not be exported to the rad file. As shown in the figure, suppressing and activating operations are simple. Meanwhile, the suppressed material properties can be clearly distinguished through the crossed-out font.


Supported OpenRadioss Materials

At present, MatEditor has supported a large number of OpenRadioss material properties, and the number is still increasing. The corresponding list of the supported properties is as follows.

Hyperelasticity and Viscoelasticity

  • LAW34 — Boltzmann
  • LAW35 — Maxwell-Kelvin-Voigt
  • LAW40 — Maxwell-Kelvin
  • LAW42 — Odgen 1/2/3
  • LAW92 — Arruda-Boyce
  • LAW94 — Yeoh 1/2/3
  • LAW100 — Polynomial, Neo-Hookean, Mooney-Rivlin2


  • LAW2 — Johnson-Cook
  • PLAS_ZERIL — Zerilli-Armstrng
  • LAW32 — Hill
  • LAW36 — Rate-Dependent Multilinear Hardening
  • LAW44 — Cowper-Symonds
  • LAW93 — Orthotropic Hill
  • LAW48 — Zhao
  • LAW49 — Steinberg-Guinan
  • LAW52 — Gurson
  • LAW57 — Barlet3
  • LAW78 — Yoshida-Uemori
  • LAW79 — Johnson-Holmquist
  • LAW84 — Swift-Voce
  • LAW103 — Hensel-Spittel
  • LAW110 — Vegter

Failure Models

  • ALTER — Glass Failure
  • BIQUD — BiQuadratic
  • COCKCROFT — Cockcroft
  • CONNECT-Connect
  • EMC — ExtendedMohr-Coulomb
  • ENERGY-Energy
  • FABRIC — Fabric
  • FLD — Forming Limit Diagram
  • GURSON — Gurson
  • HASHIN — Hashin
  • HC_DSSE — Ladeveze Delamination
  • JOHNSON-Johnson-Cook
  • MULLINS_OR — Mullins Effect
  • NXT — NXT
  • ORTHBIQUAD — Orthotropic Biquad
  • ORTHSTRAIN — Orthotropic Strain
  • PUCK — Puck
  • TBUTCHER — Tuler-Butcher
  • TENSSTRAIN — Tensile Strain
  • WILKINS — Wilkins
  • WIERZBICKI — Wierzbicki

Equation of State (EOS)

  • Compaction EOS
  • Gruneisen EOS
  • Ideal Gas EOS
  • Linear EOS
  • Murnaghan EOS
  • Nobel-Abel EOS
  • Osborne EOS
  • Polynomial EOS
  • Puff EOS
  • Stiff-Gas EOS

Additionally, some basic material properties are supported for the OpenRadioss. Such as density, linear elasticity, ALE, etc.


At present, MatEditor has satisfied most of the material types required for OpenRadioss analysis. MatEditor still actively develops and maintains the package, more unit systems and materials will be added as needed, and more output formats and open-source software will be supported. MatEditor is free for life and can be used for academic research or commercial applications. If you use MatEditor in your thesis or product, you are welcome to cite the WelSim User Manual. If you expect any new features of MatEditor, please submit them on WelSim’s GitHub page.

WelSim and the author are not affiliated with the Altair or OpenRadioss team. OpenRadioss is used only as nominative references to the open-source project and software developed and released by the Altair and OpenRadioss teams.

WelSimulation LLC is an independent engineering simulation technology provider, located in Greater Pittsburgh, PA. Its flagship product WESLIM is a general-purpose engineering simulation software with an all-in-one graphical user interface and self-integrated features.