Using the Adhesion subnode, you can add adhesion and decohesion properties to a contact pair. This functionality requires that the contact is modeled using the penalty method, and that no offset is used in the penalty stiffness function.

The selection of the Adhesion node is the same as that of its parent Contact node. If you add more than one Adhesion node under the same parent, the last one will override all the preceding nodes. If Adhesion and Friction are present under the same Contact node, the friction settings will be ignored once the adhesion criterion is fulfilled.

Select an Activation criterion, to describe the onset of the adhesion between the source and destination boundaries.

When the criterion is Pressure, enter the minimum contact pressure pn0, at which adhesion is initiated.

When the criterion is Gap, enter the distance between the source and destination boundaries δ0, at which adhesion is initiated. A negative value indicates that there must be a certain overlap before adhesion is activated.

When the criterion is User Defined, enter a boolean expression such that when it evaluates to true, adhesion is initiated.

When the criterion is Always active, the source and destination boundaries are in always in adhesive contact, unless broken by decohesion.

Select how to specify the Normal stiffness of the adhesive layer. The default is to use From contact penalty factor, in which case the stiffness is the same as the one given as Contact pressure penalty factor in the settings of the parent Contact node.

To use another stiffness, select User defined, and enter the stiffness in the normal direction Kp explicitly. This value is used in tension only; in compression the penalty factor is always used.

Select Shear stiffness defined using to be either Normal to shear ratio or Adhesive Poisson’s ratio.

For Normal to shear ratio, enter the ratio between the shear stiffness and the normal stiffness .

For Adhesive Poisson’s ratio, enter Poisson’s ratio for the adhesive layer, v, explicitly.

Select a Traction separation law. The default is No separation, in which case no decohesion will occur.

For Linear separation, Polynomial separation, or Multilinear separation enter:

For Linear separation or Polynomial separation, select the Failure criterion to be either Power law or Benzeggagh-Kenane. In either case, enter the Mode mixity exponent η.

For Multilinear separation enter the Shape factor λ.

 Solid Mechanics>Contact>Adhesion
 Multibody Dynamics>Contact>Adhesion

Physics tab with Contact selected in the Model Builder tree:
Atributes>Adhesion