Week - 5 - Modelling Spotwelds

OBJECTIVE:-

• To model spotwelds for the given assembly of parts and run a crash test.

PROCESS:-

Given:-

• Material of the crash box - Mild Steel.
• System Unit - gm/mm/ms.

CASE 1: Beam spotweld used.

Material and Section was taken as - 

Velocity:- Using the conversion method, 50kmph was converted into 13.88mm/ms.

Boundary:- At the extreme end of the crashbox, SPC_BOUNDARY was created.

Rigidwall:-

Rigidwall was created at the opposite end of the SPC_Boundary.

Contact:- AUTOMATIC_SINGLE_SURFACE and TIED_SHELL_EDGE_TO_SURFACE was used.

Control:- The Termination is set to 10ms.

Database:-

• ASCII option- ELOUT (For element Output Data), GLSTAT (Global Statistics), MATSUM (Material Energies), NODOUT (Nodal Displacement/Velocity/Acceleration data), RCFORC (Resultant Interface Forces), SECFORC (Cross Section Forces data).
• BINARY_D3PLOT

CASE 2: Solid spotweld used.

OUTPUT:-

Von-mises Stress (Beam vs Solid) :

Beam Spotweld: Min- 1.00461 MPa ; Max- 1853.29 MPa

Solid SPotweld: Min- 55.1633 MPa ; Max- 1265.53

Glstat (Beam vs Solid) :

CONCLUSION :-

• Hence from the above we can conclude that the Stress experienced in the Solid spotwelds is higer than that of Beam spotwelds.
• Solid Spotwelds also offer greater resistance as it gives more stiffness to the weld elements as comapred to beam spotwelds.