Creating Spot Welding Connection Properties

A spot weld is modeled by a connection that passes through a point and connects two surfaces. The surfaces can lie on separate parts or within a single part (for example, between overlapping faces). The parts can be meshed with either compatible or incompatible meshes. If you have a compatible mesh, a spot weld connects a node on the first surface directly to a node on the second surface. If you have an incompatible mesh, a spot weld distributes the connection between the surfaces among several nodes.

After you create a spot welding connection property, Abaqus for CATIA V5 creates a spot welding connection mesh. Table 6–11 summarizes the constraints that can be used to define a spot welding connection property in Abaqus for CATIA V5.

Table 6–11 Spot welding connection properties.

Abaqus for CATIA V5
Point Analysis ConnectionPoint Analysis Connection Within One Part

In Abaqus for CATIA V5 the connection between the surfaces can be one of the following:

Rigid

A rigid spot weld is modeled by a rigid beam connector between surfaces, as described in Table 6–12.

Table 6–12 Rigid spot weld.

Compatible MeshAbaqus EquivalentIncompatible MeshAbaqus Equivalent
Rigid beam connectorDistributing couplings and a rigid beam connector

Spring-Rigid-Spring

A spring-rigid-spring spot weld is modeled by two zero-length springs between surfaces, as described in Table 6–13. The springs have identical elastic properties and are joined by a rigid beam connector.

Table 6–13 Spring-rigid-spring spot weld.

Compatible MeshAbaqus EquivalentIncompatible MeshAbaqus Equivalent
CARDAN and CARTESIAN connectors with elastic behavior and a rigid beam connectorDistributing couplings, CARDAN and CARTESIAN connectors with elastic behavior, and a rigid beam connector

Rigid-Spring-Rigid

A rigid-spring-rigid spot weld is modeled by two rigid beam connectors between surfaces, as described in Table 6–14. The rigid beam connectors are joined by a zero-length spring.

Table 6–14 Rigid-spring-rigid spot weld.

Compatible MeshAbaqus EquivalentIncompatible MeshAbaqus Equivalent
Rigid beam connectors and a CARDAN and CARTESIAN connector with elastic behavior Distributing couplings, rigid beam connectors and a CARDAN and CARTESIAN connector with elastic behavior

Beam

A beam spot weld is modeled by a beam element between surfaces, as described in Table 6–15.

Table 6–15 Beam spot weld.

Compatible MeshAbaqus EquivalentIncompatible MeshAbaqus Equivalent
Beam elementDistributing couplings and a beam element
See Creating Mesh Properties for a description of the CATIA V5 beam profiles supported by Abaqus for CATIA V5.

You must select a user material that provides the material properties (CATIA V5 or Nonlinear) of the beam elements. The material must define the following:

  • Young's modulus

  • Coefficient of thermal expansion

If the material uses Nonlinear properties, either Young's modulus or the coefficient of thermal expansion can be temperature dependent, but not both. For more information, see Specifying Abaqus Material Properties.

Hexahedron

A hexahedron spot weld is modeled by a hexahedral connector between surfaces, as described in Table 6–16. You must select the user material that provides the material properties of the hexahedral elements. The material properties for a hexahedron spot weld must meet the same requirements as the requirements for a beam spot weld.

Table 6–16 Hexahedron spot weld.

Compatible MeshAbaqus EquivalentIncompatible MeshAbaqus Equivalent
Not supportedN/A Distributing couplings (with DOFs 1, 2, and 3 constrained) and a hexahedral element

You can request history output of relative displacements and rotations and of total, elastic, viscous, and reaction forces and moments from a spot welding connection property. The support for the history output request is the connection mesh. See Connection-type library in the Abaqus Elements Guide for a description of how Abaqus treats connectors.

This task shows you how to create a spot welding connection property between surfaces.

  1. Click the Spot Welding Connection Property icon .

    The Spot Welding Connection Property dialog box appears. A Spot Welding Connection Property object appears in the specification tree under the Properties objects set, and a Spot Welding Connection Mesh object appears under the Nodes and Elements objects set.

  2. You can change the identifier of the spot weld connection property by editing the Name field.

  3. In the specification tree, select an existing Point Analysis Connection object or Point Analysis Connection within one Part object.

    The Supports field is updated to reflect your selection.

  4. Select the type of spot weld.

  5. By default, any springs in a spot weld have no stiffness in either the translational or rotational degrees of freedom. In addition, by default a spot welding connection property is associated with the global, rectangular Cartesian axis system. To change the default behavior, click the Component Editor icon and do the following from the Spot Welding Definition dialog box that appears:

    1. Change the translational and rotational stiffness.

    2. Specify a local coordinate system for the degrees of freedom. Local coordinate systems are defined in the CATIA Part Design workbench.

    3. Click OK to accept your changes and to close the Spot Welding Definition dialog box.

  6. If you selected a beam or a hexahedron type of spot weld, click the Component Editor icon and do the following from the Spot Welding Definition dialog box that appears:

    1. From the specification tree, choose a user material with the required material properties.

    2. Specify a local coordinate system for the degrees of freedom. Local coordinate systems are defined in the CATIA Part Design workbench.

    3. Click OK to accept your changes and to close the Spot Welding Definition dialog box.

  7. Click OK in the Spot Welding Connection Property dialog box.

    Symbols representing the spot weld connection property appear at the location of the corresponding spot welding connection mesh.

  8. If necessary, double-click on the Spot Welding Connection Mesh object in the specification tree and enter the following:

    • Whether the mesh is compatible or incompatible.

    • The maximum gap between the nodes that are modeling the spot weld connection. The value is the radius of a sphere that intersects nodes on both of the parts that are being welded.

    • The diameter of a hexahedron spot weld.

  9. Right-click on the spot welding connection mesh object in the specification tree, and select Update Mesh from the menu that appears.