The Settings Window for Material

The window for (

) summarizes the predefined or user-defined material properties for a material. This is where you can add or change material properties to fit your model and assign the material to all types of geometric entities: domains (most common), boundaries, edges (3D models only), or points. Also see Material Link and Switch for Materials.

After adding a material (see The Add Material Window and The Material Browser Window), click the Material node (for example, or ) in the . The window for opens.

A standard node in the global component can turn into a layered material by adding a property group. After that, it can be linked by a Layered Material Link

In the field, enter a suitable label for the material. If you defined global materials for a user-defined material library, the label becomes the name of the material. See also below. You can also use the field to change the identifier. This setting also changes the tag and therefore makes it possible to control the scope of variables and functions that the material defines.

This section is available for materials in a component. Assign the material to some or all entities on a specific — , , (3D only), or — on the geometry in the window (the geometry in the model).

	By default, the first material in the Component is active in all domains (or all boundaries or edges if the Component only contains surfaces or edges). By assigning other materials to some or all domains, the first material is overridden and remains active only in domains where no other material, added below it in the Materials branch, is active.

	If the Component contains features on different geometric entity levels, such as solid mechanics in domains coupled to beams on edges, and the features use the same material, you need to add two Material nodes with the same material, one defined in the domains, and the other defined on the edges.

This section, available for materials in a component, shows if the material, in some or all parts of the geometry where it is active, is overridden by another material added underneath it in the Materials branch, or if it overrides another material above it.

The list shows the names of the materials that override this material. The list in the section displays for the geometric entities in which this material is overridden.

The list shows the names of the materials that this material overrides.

	This section only appears in Material nodes that are single layer material. See Single-Layer Materials.

Select a defining the principal directions of the laminate. Only coordinate systems can be selected.

Choose a — , , , or . This controls the possible offset of the material from the geometrical boundary on which the mesh exists (the reference surface). For , enter a value for the . The value 1 corresponds to , and the value −1 corresponds to . Values may be outside the range −1 to 1, in which case the reference surface is outside the laminate.

The setting is only used by physics features where the physical behavior depends of the actual location, such as structural shells.

By clicking the (

) button, you get a preview plot of the single layer material, including the location of the reference surface. This plot looks similar to Figure 9-12, but there is only a single layer. You can also click the downward pointing arrow to choose (

) button or (

) button, which adds the preview plot as a new plot group under .

You can add material properties to the material if they are not already included. To do so, browse the available material property categories (, , and so on), and select a material property or a collection of material properties in one of the property groups or material models that appear under the main level of material property categories. Right-click the material property or property group and select , or click the button (

) to add the material property or group of properties to the material.

	Review the properties listed in the Material Contents table before adding new material properties.

For example, under select and right-click to or click the button (

). If you add a material model like the with more than one property, all of its material properties are added to the table. In this example, a node is added to the and its associated properties are added to the table.

	To delete a property group, right-click the property group node (in the Model Builder) and select Delete (). The Basic property group cannot be deleted.

Material properties can be added to the group or to any from two locations — the windows for and .

•

When material properties are added from the node’s or a user-defined group node’s window for , they are listed under and in that window.

•

When material properties are added from the window for , the available material properties are listed under and are added to the list under with the property group listed. The list under also contains material properties added from a subnode with a window for .

The setting decides how materials behave and how material properties are interpreted when the mesh is deformed. Select for materials whose properties change as functions of material strain, material orientation, and other variables evaluated in a material reference configuration (material frame). Select for materials whose properties are defined only as functions of the current local state at each point in the spatial frame and for which no unique material reference configuration can be defined.

Simply put, materials associate material properties with specific pieces of the material, and the properties follow the material as it moves around. In particular, a solid material may be inherently anisotropic, meaning that its axes rotate together with the material. The choice, in contrast, applies typically to liquids and gases whose properties are associated with fixed points in space and insensitive to local rotation of the material. Such materials are inherently isotropic when studied in isolation but can exhibit anisotropy induced by external fields. In practice, this means that any anisotropic tensor properties in a nonsolid material must be functions of some external vector field.

This section lists all of the material properties that are defined for the material or required by the physics in the model. The table lists the , , , and for the material property as well as the to which the material property belongs. The corresponds to the subnodes in the with the same name. If required, edit the values or expression for the property’s .

The left column provides visual cues about the status of each property:

•

A stop sign (

) indicates that an entry in the column is required. It means that the material property is required by a physics feature in the model but is undefined. When you enter a value in the column, the material property is added to its property group.

You can change the value for any property that is not synchronized by editing its value directly in the column, or, for a selected property, click the button (

) or right-click and choose to enter a value in the window that opens. If the property can be anisotropic, you can choose to enter the values in one of these forms: , , , or . The column lists the variable names corresponding to the degree of anisotropy. For example, for a symmetric electrical conductivity, it contains . For an isotropic electrical conductivity, it contains , where sigma_iso is the name of the variable for the isotropic electrical conductivity (available as, for example, mat1.def.sigma_iso).

You can right-click any defined material property in the table and choose ; the focus in the model tree then moves to the node that requested that material property. If there are more than one node that requests that material property, a dialog box appears, where you can choose which of those nodes to go to. Also, for nodes such as and , you can right-click any defined material property and choose to move to the material node that is the source of that material property.

	Select the Material Library Settings check box in the Show More Options dialog box to display this section for Material nodes under Global Definitions.

In this section, you can define properties for materials in a user-defined material library to create a set of materials with varying material phase and orientation or variation.

Click the button (

) to update the label, which becomes the name of the material in the user-defined material library.

From the list, choose , , , or to define the material’s phase. This setting is not available if the parent node has its set to , in which case the phase is defined in that node’s settings.

In the field, enter some orientation or variation that represent this material.

The settings in this section, available for materials in a component, make it possible to control or change the default appearance of a material in the Graphics window when working in the materials or physics parts of the model tree.

	In 3D components, the material is rendered including color and texture when Scene Light is active. In 2D models and in 3D components, when Scene Light is turned off, only a change of color is visible.

The list provides quick settings approximating the appearance of a number of materials — , , , , , , , , , , , , , , , , , , and more. Select to make further adjustments of the specific settings for colors, texture, reflectance, and so on. The default custom settings are inherited from the material selected last from the list. If you have chosen a family other than , click the Customize button to define a custom material.

For each of these properties, select a standard color from the list: , , , , , , , , or , or choose button to define a custom color from the color palette that becomes available underneath the list of colors.

The combination of , , and gives a 3D object its overall color:

•

is the color of the light of a specular reflection (specular reflection is the type of reflection that is characteristic of light reflected from a shiny surface).

•

represents the true color of an object; it is perceived as the color of the object itself rather than a reflection of the light. The diffuse color gets darker as the surface points away from the light (shading). As with Ambient color, if there is a texture, this is multiplied by the colors in the texture, otherwise it is as if it has a white texture.

•

is the color of all the light that surrounds an object; it is the color seen when an object is in low light. This color is what the object reflects when illuminated by ambient light rather than direct light. Ambient color creates the effect of having light hit the object equally from all directions. As with Diffuse color, if there is a texture, this is multiplied by the colors in the texture; otherwise, it is as if it has a white texture.

	For examples of specular, diffuse, and ambient light, which are related to these definitions, see About the 3D View Light Sources and Attributes.

Select the check box to define a custom coordinate basis for the brush lines. The default values for the brush line axes represent the global Cartesian coordinate system. Specify other x, y, and z coordinates for the and theif desired. To specify other coordinates for the , first select the check box.

Select the check box to add normal vector noise and brush lines. Normal mapping is a texture that disturbs the normals when calculating lighting on the surface (also called bump mapping). This causes the surface to look rough and textured. The default and are taken from the material. You can choose the type from the list: (a uniform distribution) or .

Enter other values as needed, or click to clear the check box.

•

The is the size of the noise disturbances. A small value creates smaller features on the texture. A value between 0–10 is suitable.

•

Add brush lines if desired by choosing an option from the list: (the default), , , , , , , , , , or .

	The “m” in xm, ym, and zm above represents that the coordinates are with respect to the material basis (custom basis).

Select the check box if you want to blend the appearance with an additional color that is added on the surface using noise. The settings are similar to those for the normal mapping above, but you can also choose the color to add from the list and choose a between 0 and 1. The is a parameter that affects the appearance of the added color.

The default is 1.

The default — or — is based on the material. Select instead as needed; it has no additional settings.

The different lighting models provide a set of techniques used to calculate the reflection of light from surfaces to create the appropriate shading. For example, a specular highlight is the bright spot of light that appears on shiny objects when illuminated. Specular highlights are important in 3D computer graphics because they provide a strong visual cue for the shape of an object and its location with respect to light sources in the scene.

For , the default is 64. The specular exponent determines the size of the specular highlight. Typical values for this property range from 1 to 500, with normal objects having values in the range 5 to 20. This model is particularly useful for representing shiny materials.

For , the default settings are taken from the material. The Cook–Torrance lighting model accounts for wavelength and color shifting and is a general model for rough surfaces. It is targeted at metals and plastics, although it can also represent many other materials, and it includes the following settings.

•

The parameter is a value that affects how metallic the material appears to be. A less metallic material reflects less of the environment. A nonmetallic material cannot reflect the environment

•

The parameter is an artificial effect that makes surfaces that are parallel to the view direction more white. It also adds specular highlighting and reduces the effect on the environment reflections from the normal mapping.