Model Based On The Life Of The Audience Equivalent Damage Test

The project of this paper is supported by Jiangsu Natural Science fund. Material 's static toughness is the area of the stress-stain chart, which means the work absorbed before its break. It integrative reflects the strength and the ductility of the material. This paper studies the relationship between the static toughness and fatigue failure firstly, then getting the damage formula expressed by toughness. In this paper, fatigue test are performed on various alternative stress levels of a group of fixed cycle number. Meanwhile, the material toughness that is selected as fatigue damage parameter is measured in the tests and a group of curves are obtained, which express the relevancy of the damage quantity and alternative stress level. These curves are then transformed into equivalent damage curve family. Thus the full fatigue damage field is shown . In the paper, the damage cumulative model and the fatigue life formula are induced from the complex loading equivalent damage curves, which is based on the reasonable equivalent damage curve function . In order to examine the description of the gained damage linear equations under complex loading circumstances, a comparison of the theoretical life prediction with the test results, which are obtained by testingthe two material ---LY12CZ and SOCrMnSiA, is made and it can befound that the data gained in the tests are well fit in with the damage equation. Thereby the equivalent damage model is directly credible.