IN SITU TEM OBSERVATION OF EMBRITTLEMENT OF ALUMINUM ALLOY BY LIQUID METAL
铝合金液体金属脆断过程的TEM原位观察

The liquid metal-induced embrittlement (LME) of 7075 aluminum alloy was investigated by using a special constant deflection device. The change in dislocation configuration ahead of a loaded crack tip for 7075 aluminum alloy before and after adsorping of Hg 3%Ga atoms, and the initiation of liquid metal-induced microcrack have been observed in TEM. The results showed that chemisorption of liquid metal atoms could facilitate dislocation emission,multiplication and motioll. When the chemisorption - facilitating dislocation emission and motionreach to a critical condition, a microcrack will initiate in dislocation free zone (DFZ) or at the crack tip, and propagate in cleavage mode.