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 # RAMaterialsInteractionCollection

 Last update: 17.07.2025 

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### *class* RAMaterialsInteractionCollection

Rocky PrePost Scripting wrapper for the collection of materials interactions in a project.

This wrapper corresponds to the “Materials Interactions” item on the project’s data tree. Retrieve the [`RAMaterialsInteractionCollection`](#generated.RAMaterialsInteractionCollection) from a [`RAStudy`](RAStudy.md#generated.RAStudy) via:

```python
interaction_collection = study.GetMaterialsInteractionCollection()

```

Instances of the [`RAMaterialsInteractionCollection`](#generated.RAMaterialsInteractionCollection) class act as regular Python lists and can be iterated on, individual materials accessed via index, etc:

```python
interaction_1 = interaction_collection[3]
for interaction in interaction_collection:
    interaction.SetAdhesiveFraction(80, '%')
interaction_2 = interaction_collection.GetMaterialsInteraction('Default Particles', 'Default Boundaries')

```

Note that individual interactions can’t be created or removed by the user: they are created and removed as necessary as new materials are created or removed.

Items in this list are of type [`RAMaterialsInteraction`](RAMaterialsInteraction.md#generated.RAMaterialsInteraction).

**Methods:**

NameDescription[`Clear`](#generated.RAMaterialsInteractionCollection.Clear)()Unused: Materials Interactions are automatically deleted when Materials are created.[`GetMaterialsInteraction`](#generated.RAMaterialsInteractionCollection.GetMaterialsInteraction)(material\_1, material\_2)Get the materials interaction for the given pair of materials.[`New`](#generated.RAMaterialsInteractionCollection.New)()Unused: Materials Interactions are automatically created when Materials are created.[`Remove`](#generated.RAMaterialsInteractionCollection.Remove)(item)Unused: Materials Interactions are automatically deleted when Materials are created.<a id="generated.RAMaterialsInteractionCollection.Clear"></a>

#### Clear()

Unused: Materials Interactions are automatically deleted when Materials are created.

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#### GetMaterialsInteraction(material\_1, material\_2)

Get the materials interaction for the given pair of materials.

For both material\_1 and material\_2 parameters, the parameter can be either an instance of [`RASolidMaterial`](RASolidMaterial.md#generated.RASolidMaterial) or the material’s name.

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#### New()

Unused: Materials Interactions are automatically created when Materials are created.

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#### Remove(item)

Unused: Materials Interactions are automatically deleted when Materials are created.