Creo Simulate > Modeling Structure and Thermal Problems > Properties > Materials > Guidelines and Background > Opening a Model containing Materials from a release before Pro/ENGINEER Wildfire 3.0
  
Opening a Model containing Materials from a release before Pro/ENGINEER Wildfire 3.0
When you open a model that was saved in a release before Pro/ENGINEER Wildfire 3.0, you must first enter Creo Simulate before you work with materials in Creo Parametric. Invoking Creo Simulate will initiate a one-time conversion of material properties from the data format of a release before Pro/ENGINEER Wildfire 3.0 to the new Pro/ENGINEER Wildfire 3.0 data format. This is especially important if your material has properties that are a function of temperature. After conversion, you can view the functions and their associations with materials in Creo Parametric.
 
* In Creo Parametric, if you edit the functions associated with the material created in Creo Simulate before their conversion, you may lose your data associated with the material.
A similar conversion also happens for non-isotropic materials, fatigue properties, failure criteria, and materials with parameters. When you open a model in Creo Parametric for the first time, the material value fields show Zero for transversely isotropic and orthotropic materials, None for fatigue properties and failure criteria, and numerical values for the materials with parameters. When you open the model in Creo Simulate, the materials are converted and the material value fields have the required values.
If you have a material definition with the parameter Cost, after conversion it is available under the User Defined tab in the Materials dialog box.