Mechanism modelling and validation of ultrasonic vibration-assisted laser processing on metal surfaces

•A model of the ultrasonic vibration-assisted laser ablation mechanism was developed and validated.•A mathematical model for the lap rate of ablation pits was developed.•The rules for the selection of machining parameters for special trajectories were given. At present, with the development of high technology and materials science, the traditional laser processing (NLP) method is no longer sufficient for the preparation of special surface profiles in the field of cutting-edge manufacturing. Ultrasonic vibration assisted laser processing (UVLP) is gradually being developed by researchers, but is largely experimental study in nature. In this paper, a mathematical model of the transverse ultrasonic composite laser ablation trajectory of metals is developed, and the feasibility of the model is verified by numerical simulations and experiments by using aluminum as the base material. Error rates for ablation widths and trajectory cycle times range from 2.18% to 6.50%. The error of the crater lap rate is 3.88%-19.62%. The influence of ultrasonic and laser frequencies on the ablation trajectories is analyzed. The frequency selection rules for the preparation of special morphologies are given. This study presents a theoretical model of a new processing method, which has a guiding significance for the parameters selection of laser processing and the special surface morphology preparation.