The experiments on notched specimens of an Aluminium alloy indicat that the notch fatigue life can be increased by a tensile over-pre loading but decreased by a compressive over-pre loading.

• 预过载拉伸可提高铝合金缺口疲劳寿命,但效果不及喷丸;过载量太大还使寿寿命趋于子下降。