Synthesis of Functional-Gradient Material by Direct Laser Deposition with Ultrasonic Impact

The possibility of synthesizing a functionally graded material by direct laser deposition (DLD) with ultrasonic excitation was investigated. A Langevin-type transducer with an output of 100 W and a frequency of 20 kHz was used as the high-frequency vibration source. The transitional structure from EuTroLoy 16316D.04 stainless steel to the nickel alloy Inconel 625 was studied. Thanks to the ultrasonic excitation, a structure composed of equiaxed columnar dendrites was obtained. The elemental distribution along the central line of the specimens’ cross-section was analyzed. The influence of ultrasonic vibrations on the relative contents of Fe and Ni was noted, producing a smoothing of the elemental composition across the transition from one composition to the other. Microhardness analysis along a line parallel to the central line of the cross-section showed a decrease in microhardness when transitioning from 100% Inconel 625 to 100% stainless steel, while the microhardness measured with ultrasonic excitation was 5–7% higher than that measured without it.