This module window is subdivided into two parts. The upper part lists all materials created in RFEM or RSTAB. The Material Properties section shows the properties of the current material, that is, the table row currently selected in the upper section.
Materials that won't be used in the design are grayed out. Materials that are not allowed are highlighted in red. Modified materials are displayed in blue.
Chapter 4.3 of the RFEM manual, or Chapter 4.2 of the RSTAB manual, describes the material properties that are used for the determination of the internal forces (Main Properties). The properties of the materials that are required for the design are also stored in the global material library. These values are preset (Additional Properties).
To adjust the units and decimal places of the properties and stresses, select on the module menu Settings → Units and Decimal Places (see Chapter 7.3).
The materials defined in RFEM or RSTAB are preset but you can modify them anytime:
Click the material in column A to activate the field.
Then, click the 
button, or press the function key [F7] to open the material list.
According to the design concept of the Standard [1], only materials of the Steel category can be selected.
After the material transfer, the design-relevant Material Properties are updated.
If you change the material description manually and the new entry is already listed in the material library, RF-/STEEL EC3 will import the material properties as well.
The material properties are generally not editable in the RF-/STEEL EC3 add-on module.
Many materials are stored in the database. To open the material library, click on the module menu
Edit → Material Library
or use the button shown on the left.
The Steel material category is preset in the Filter section. You can select the desired material grade from the Material to Select list; then you can check the properties in the dialog section below.
Click [OK] or use [↵] to transfer the selected material to Window 1.2 of RF-/STEEL EC3.
Chapter 4.3 of the RFEM manual, or Chapter 4.2 of the RSTAB manual, describes how to filter, add, or reorganize materials.
In the library, you can also select materials of the categories Cast Iron and Stainless Steel. However, please check whether these materials are allowed by the design concept of the Standard [1].