Assessment of V96zs alloy properties under conditions simulating a thermal cycle of fusion welding

The dependence of the fraction and the size of inclusions of intermetallic phases based on Zr and Sc, which change during heating under welding, with the Al–Zn–Mg–Cu alloying system simulated on samples of the high-strength V96zs aluminum alloy was established. Their influence on the fracture toughness parameters during crack initiation and propagation in the metal at the fusion line and the heat-affected zone of the joints was shown. The cooling rate of the samples specified the size and shape of intermetallic inclusions located along the grain boundaries. The formation of coarse phase inclusions of various lengths, ellipse or close to sphere-like, causes the appropriate mechanism of alloy fracture.