Note:  In extreme cases, such as with rapid temperature changes or large thermal strains, convergence issues may arise. During the Newton-Raphson (NR) process, the thermal-mechanical coupling is not fully bidirectional. Specifically, temperature changes affect deformation, but deformation does not affect temperature within an iteration. This sequential update of thermal and mechanical responses may lead to convergence issues, particularly under extreme conditions. For example, when thermal entities are related to state variables such as position, velocity, acceleration, force, variable, and differential equation, significant temperature changes can occur. If these large temperature changes result in significant volume changes, integration and NR failures will occur. To mitigate such failures, you should reduce the error tolerance for the NR convergence or the step size.