36.2.3 Contact properties for general contact in Abaqus/Standard
Products: Abaqus/Standard Abaqus/CAE
References
Overview
Contact properties:
define the surface interaction models that govern the behavior of surfaces when they are in contact; and
can be applied selectively to particular regions within a general contact domain.
Assigning contact properties
The default contact property model in Abaqus/Standard assumes “hard” contact in the normal direction, no friction, no thermal interactions, etc. You can assign a nondefault contact property definition (surface interaction) to specified regions of the general contact domain.
Contact properties for general contact in Abaqus/Standard are assigned at the beginning of the analysis and cannot be modified across steps, with an exception for changes to the friction model, as discussed below.
The surface names used to specify the regions where nondefault contact properties should be assigned do not have to correspond to the surface names used to specify the general contact domain. In many cases the contact interaction will be defined for a large domain, while nondefault contact properties will be assigned to a subset of this domain. Any contact property assignments for regions that fall outside of the general contact domain will be ignored. The last assignment will take precedence if the specified regions overlap.
| Input File Usage: | *CONTACT PROPERTY ASSIGNMENT surface_1, surface_2, interaction_property_name |
This option must be used in conjunction with the *CONTACT option and should appear at most once; the data line can be repeated as often as necessary to assign contact properties to different regions. If the first surface name is omitted, a default surface that encompasses the entire general contact domain is assumed. If the second surface name is omitted or is the same as the first surface name, contact between the first surface and itself is assumed. Surfaces can be defined to span multiple unattached bodies, so self-contact is not limited to contact of a single body with itself. If the interaction property name is omitted, the unnamed set of default contact properties in Abaqus/Standard is assumed. If an interaction property name is specified, it must also appear as the value of the NAME parameter on a *SURFACE INTERACTION option in the model portion of the input file. |
| Abaqus/CAE Usage: | Use the following options to assign a global contact property to the entire general contact domain: |
Interaction module: Create Interaction: General contact (Standard): Contact Properties: Global property assignment: interaction_property_name Use the following options to assign contact properties to individual surface pairs: Interaction module: Create Interaction: General contact (Standard): Contact Properties: Individual property assignments: Edit: select the surfaces and the contact property in the columns on the left, and click the arrows in the middle to transfer them to the list of contact property assignments In Abaqus/CAE you must assign a global contact property; Abaqus/CAE does not assume a default contact interaction property. Contact properties assigned to individual surface pairs override the global assignment. |
Changing friction properties during an analysis
The friction properties associated with a given named surface interaction definition can be modified in any particular step of an Abaqus/Standard analysis, as discussed in “Changing friction properties during an Abaqus/Standard analysis” in “Frictional behavior,” Section 37.1.5.
Example
The following contact property assignments are specified below as model data in a general contact analysis:
a global assignment of contProp1 to the entire general contact domain;
a local assignment of contProp2 to self-contact for surf1;
a local assignment of the default Abaqus contact property to contact between surf2 and surf3; and
a local assignment of contProp3 to contact between the entire contact domain and surf4. The friction coefficient for contProp3 is reset from the initial value of 0.20 to 0.05 in the second step.
*SURFACE INTERACTION, NAME=contProp1 *FRICTION 0.1 *SURFACE INTERACTION, NAME=contProp2 *FRICTION 0.15 *SURFACE INTERACTION, NAME=contProp3 *FRICTION 0.20 *CONTACT *CONTACT INCLUSIONS, ALL EXTERIOR *CONTACT PROPERTY ASSIGNMENT , , contProp1 surf1, surf1, contProp2 surf2, surf3, , surf4, contProp3 … *STEP Step1 *STATIC … *END STEP *STEP Step2 *STATIC … *CHANGE FRICTION, INTERACTION NAME=contProp3 *FRICTION 0.05 *END STEP