Abstract: When a plate containing a crack is excited by intensive ultrasonic pulses, a coupled three-dimensional thermo-mechanical FEM model is built to simulate the phenomenon of dynamical contact and frictional heating between both lateral faces of the crack. In the FEM model, the high-power ultrasonic transducer is modeled by using a piezoelectric thermal-analogy method, and the dynamical interaction between both faces of the crack is modeled using a contact-impact theory. The penalty method is used as contact-impact algorithm to simulate the contact behavior between both faces of the crack. During the FEM simulation, the frictional heating taking place at both faces of the crack is quantitatively calculated, and the vibration characteristics of the plate, the dynamical contact behavior of two surfaces of the crack and the temperature distribution around the crack zone were subsequently analyzed. The computational results could reasonably explain reasonably the phenomena observed in ultrasonic infrared imaging technique.