In situ investigation of Al bicrystal embrittlement by liquid Ga using synchrotron imaging Original Research Article

The penetration behaviour of liquid Ga along two different types of symmetrical tilt Al bicrystals is analysed as a function of tensile load applied normal to the boundary plane by means of synchrotron radiation X-ray micro-radiography. A direct relation between the grain boundary energy and the applied load required to promote liquid metal embrittlement is evidenced. Analysis of the in situ penetration experiments allows us to establish a link between crack velocity and the stress intensity factor. The thickness of the intergranular liquid Ga film is compared to the expected crack opening which accompanies crack propagation in mode I loading conditions.