# 2.2.7: Specify Materials

Materials can be either defined by manually setting their mechanic properties or by selection from a library of predefined materials (see fig. 2.2.7.1 (3)). Materials attach to cross sections. There are two options for assigning materials:

![Fig. 2.2.7.1: Definition of materials via element names](https://1646753513-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-M9XteyGDAU3Odla53cC%2Fsync%2F4add2d8732d3d616c4cdfc7de50a03766eb3a9bf.png?generation=1591871157293367\&alt=media)

1. Assignment via the **“Assemble”**-component (see fig. 2.2.7.1). The **“Elem|Id”** input-plug specifies the names of the elements to which the material shall 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 to elements directly but to the element’s cross section. 
2. Direct input at the **“Cross Section”**-component like in fig. 2.2.7.2.

![ Fig. 2.2.7.2: Definition of a material directly at the "Element"-component](https://1646753513-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-M9XteyGDAU3Odla53cC%2Fsync%2F415840f0fb53f21e82bbf2b319ceb44f4166a17c.png?generation=1591871157692766\&alt=media)

Fig. 2.2.7.1 shows how materials can be defined by element names **“Elem|Id”**: definition of an isotropic custom material (1); definition of an orthotropic custom material (2); selection of a material from the material library (3).

{% 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 ](https://manual-1-3.karamba3d.com/2-getting-started/karamba3d-entities#default-settings)will be used.
{% endhint %}