Yes, it is possible to simulate high cycle fatigue (HCF) crack growth based on time in Abaqus, but not directly by defining amplitude and time. Abaqus doesn't have a built-in feature to directly link time to load cycles. To simulate high cycle fatigue (HCF) crack growth based on time in Abaqus, you'll need to use a cyclic loading step to define the amplitude and frequency, and then employ XFEM to model crack initiation and propagation. A suitable fatigue crack growth law, like the Paris-Erdogan law, should be applied to predict crack growth rates based on stress intensity factors. The analysis is iterative, with the crack geometry updated after each cycle and the simulation repeated. Key considerations include time step size, mesh refinement, material model, and convergence monitoring. While this approach is more complex than a direct time-based simulation, it provides a more accurate representation of HCF crack growth.