Abstract:

A study is described on the attenuation of residual stress of a cold expanded hole and its experimental results. The residual stress of the cold expanded hole of aluminum alloy LY12CZ and LC4CS, when bush is not used, has an obvious trend towards attenuation, and the change in attenuation is characterized by different speed forms. According to the greatest critical value principle for cold expanded strengthening, this paper puts forward a concept of cold expanded saturation degree. In accordance with the different change features of the attenuation curves, the authors analyze the cause,condition and the effect among main parameters.

Key words: cold expanded hole, cyclic stress, attenuation speed, cold expanded saturation degree