The Influence of Ultrasonic Impact on Mechanical and Tribological Properties of Stainless Steel During Direct Laser Deposition

The process of direct laser deposition with ultrasonic exposure of stainless steel samples is considered. Three groups of samples are prepared according to the developed deposition strategies to study the mechanical and tribological characteristics. It is found that additional ultrasonic exposure leads to an increase in the hardness of the deposited layers by 8.2%. At the same time, the hardness of the main zone of the metal does not undergo significant changes. The tensile test results show an average increase in strength value by 44.3 MPa compared to the standard method, which is equivalent to 8.9%. Studies of tribological characteristics allow one to conclude that the wear resistance of samples obtained with ultrasonic exposure increases by 26.3%. The use of ultrasonic vibrations is fraught with the changes in microstructure and stream structure of the melt pool. These changes are thought to be caused by cavitation and acoustic streams.