Phase and structural transformations of welds in metal upon high-velocity impact

The change in the structure of welds obtained using a new welding wire and subjected to high-velocity impact was investigated by optical and scanning electron microscopy and X-ray diffraction analysis. It is shown that after welding, a structure of martensite, $\delta$-ferrite, and a metastable austenite is formed in the weld metal. Subsequent intense exposure leads to hardening of the weld metal due to the transformation of metastable austenite into strain-induced martensite. Kinetic microindentation of the welds was performed.