关键词: 铝锂合金, 疲劳寿命, 断裂特征

Abstract: The fatigue life of aluminum-lithium alloy 8090+Ce is investigated, and compared with traditional aluminum alloy 2024. Specific emphasis is placed on researching the fracture feature of fatigue crack initiation, short crack growth and stable-loss growth for aluminum-lithium alloy 8090+Ce. The fatigue life of aluminum-lithium alloy 8090+Ce is inferior to that of traditional aluminium alloy 2024. The microcracks in grain boundaries are intergranular growth in longitude, and finally enter in non-growth condition. The growth mode of short cracks associating with the main fracture surface for this alloy is transgranular along coarse slip bands. The brittle fatigue strips, which are wider and straighter, are exhibited. The final fracture mode is transgranular along coarse slip bands together with transgranular and intergranular tear.

Key words: aluminum-lithium alloy, fatigue life, fracture feature