Study on microstructure evolution of ultrasonic assisted laser cladding based on phase field method

Abstract In order to explore the influence of ultrasonic assistance on the evolution law of microstructure in laser cladding, a dynamic model of dendrite growth in ultrasonic-assisted laser cladding is established in this paper. The phase field control equation is established based on the coupling of the phase field method and the temperature field. Ultrasonic vibrations of different amplitudes are added in the form of high-frequency disturbances in the phase field control equation. The morphological characteristics of dendrite growth with and without the action of ultrasonic energy field are analyzed. The influence law of ultrasonic amplitude on the morphological evolution behavior of dendrites in laser cladding layers is discussed. The solidification structure of the cladding layer is experimentally characterized through ultrasound-assisted laser cladding experiments to verify the reliability of the simulation results. In the ultrasound-assisted laser cladding experiments with the same amplitude, the refinement degree of the microstructure of the cladding layer is the most significant, and its microhardness is the greatest.