> For the complete documentation index, see [llms.txt](https://manual.karamba3d.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://manual.karamba3d.com/beta/2-getting-started/2-getting-started-1/setting-up-a-structural-analysis/2.2.7-specify-materials.md).
# 2.2.7 Specify Materials
Materials can be defined either by manually setting their mechanical properties or by selecting from a library of predefined materials (see Fig. 2.2.7.1, item 3). Materials attach to cross-sections. There are two options for assigning materials:
* **Assignment via the “Assemble” Component:** Use the **“Elem|Id”** input plug to specify the names of the elements to which the material should be attached. Alternatively, a regular expression can be used to select elements. Leaving **“Elem|Id”** empty sets the material for all elements. Materials are not attached directly to elements but to the element’s cross-section.
* **Direct Input at the “Cross Section” Component:** As shown in Fig. 2.2.7.2.
Fig. 2.2.7.2: Definition of a material directly at the "Element" component.
Figure 2.2.7.1 illustrates how materials can be defined by element names **“Elem|Id”**:
1. Definition of an isotropic custom material.
2. Definition of an orthotropic custom material.
3. Selection of a material from the material library.
{% hint style="info" %}
Assignment via the **“Assemble”**-component overrides direct assignment in the cross section.
{% endhint %}
{% hint style="info" %}
Should you not assign a material to your beam or shell elements, the [default material ](/beta/2-getting-started/2-getting-started-1/karamba3d-entities.md#default-settings)will be used.
{% endhint %}
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