抄録
Fatigue properties of super duralumin plate (SDH) subjected to two different values of cyclic stress were investigated. The results obtained are summarised as follows:
(1) When the value of cyclic stress to be applied primarily is below the static yield point, the following relation has been found:
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where Ni is the number of cycles of a stress applied alone at which the specimen shall be failed, and Ni' is the number of cycles of the same stress to be applied as a primary stress, or as a secondary one at which the specimen shall be failed. If the value of a primary cyclic stress is greater than of the subsequent cyclic stress, and the number of cycles of the former is relatively larger, the relation mentioned above becomes as follows:
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(2) When the value of a primary cyclic stress is nearly the static yield point, the relation (1) changes as follows:
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(3) When the value of a primary cyclic stress is about the altimete tensile strength, the relation has been obtained as follows:
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