Numerical and experimental investigation into temperature field and profile of Stellite6 formed by ultrasonic vibration-assisted laser cladding

Abstract

Laser cladding technology is widely used in component processing. However, the rapid temperature variation of the molten pool during the cladding could lead to the poor quality of the cladding track. The ultrasonic vibration-assisted laser cladding technology is studied in this work to improve the mechanical properties of the cladding layer. According to the process of the ultrasonic vibration-assisted laser cladding, the model is established by the cellular automata method to calculate the profile and the temperature field of the cladding track. The laser energy distribution and the powder distribution of the four-way powder feeding nozzles are studied by the model. This model considers the influence of the ultrasonic vibration on the profile and the temperature field of the cladding track. The energy model of the ultrasonic vibration is established, and the energy transmitted from the ultrasonic vibration to the molten pool is added to the droplet forming method. Therefore, the model applies to the calculation of the profile and the temperature field of the cladding track with ultrasonic vibration. Then, experiments were carried out on Stellite6 to explore the effect of the ultrasonic vibration on the profile, temperature field and mechanical properties of the cladding track. The results show that the relative error of the model in calculating the profile of the cladding track is not more than 10 %, and the model can accurately calculate the temperature field. The ultrasonic vibration can refine the grains of the cladding track and increase the average microhardness by 19.9 %. This study will provide an essential theoretical basis for optimizing the ultrasonic vibration-assisted laser cladding process, reducing micro defects, and improving the quality of the cladding layer.