Kinetics and mechanism of copper fracture due to deformation in surface-active baths

The authors propose a molecular mechanism of subcritical crack development under conditions of liquid-metal embrittlement. It is suggested that cracks develop as a result of diffusive mass transfer from the tip of a crack and that the role of the liquid is to provide a wide and “fast” diffusion channel. The specific action of surface-active baths here is connected with the atomic roughness of the crystal-bath interface, at rather low temperatures already, which leads to a higher concentration of dissolution centers at the crack front and produces conditions at the interface favorable to diffusion currents in the bath. It is demonstrated that this model of fracture correctly depicts the basic trends of subcritical crack development in the copperbath (Bi-Pb) system and may be used for analyzing the fracture kinetics in other systems too.