47.3. Modeling

The simple geometry for this example is created and meshed in Mechanical APDL.

Figure 47.3: Meshed Solder Joint

Meshed Solder Joint

The model is meshed with the SOLID226 coupled-field element. CONTA174 contact elements are defined between the solder ball and the copper conductors. Both the SOLID226 and CONTA174 elements have the following degrees of freedom needed for this analysis: concentration (CONC), temperature (TEMP), voltage (VOLT), and displacement (UX, UY, UZ). For the SOLID226 elements, KEYOPT(1) = 100111 activates these degrees of freedom. For the CONTA174 elements, KEYOPT(1) = 12 activates these degrees of freedom.

Contact is used to demonstrate the structural-thermal-electrical-diffusion coupling capability of the contact elements. Although it is not strictly needed in this model, contact may be useful in some applications where a contact resistance is desired. The contact elements are assigned properties that produce continuity of the fields.