Experimental Study On Fatigue Properties Of Combined Field Apron

According to the new combined field apron, the paper is to carry out study on its fatigue properties by means of a combined theoretical and experimental approach. With strict technical requirements, the combined field apron is required tomeet a number of technical indexes. In addition, honeycomb sandwich is different from common high cycle fatigue, making study on fatigue properties of combined field apron become a matter of urgency.This paper firstly presents the structure form and making technology of combined field apron, summarizes its main technical indexes, and analyzes the possiblepreparation defect in preparation process and its impact on honeycomb properties. Besides, on base of the making technology of the honeycomb core, the paperis to make an equivalent calculation of honeycomb cell-wall thickness; and basedon representative volume method, Y shape model is adopted to make a deduction of honeycomb sandwich parameters. The paper verifies the accuracy of apronfinite element model simplified by the deduced parameters.With theoretical analysis on fatigue mechanism of combined field apron, the paper is to get the fatigue test load of combined field apron according to the specific application conditions of the apron. And the paper is to get the result fromthe comparison of the flat crush test of honeycomb sandwich blocks and the calculation results by ANSYS that buckling instability is generated in case the honeycomb is less than its material yield stress, making the honeycomb measured displacement greater than finite element calculated value. Fatigue test finally measures out the fatigue life of the apron cell block is3000, and gets displacement-life curve. From ANSYS calculation results, it can be seen that the apron exist local high-stress area at36kN static loads, and that the stress value is higher than the yield stress of aluminum alloy. From photos of honeycomb blocks at depression area after fatigue test, it can be seen that apron fatigue failure is mainly resulted from honeycomb buckling deformation.Through the comparison of test data and finite element calculation results, thepaper studies main fatigue failure forms of combined field apron. And in combination of experimental study and theoretical analysis, the paper provides the evidence that the service life of combined field apron meets the application requireme nts, analyzes fatigue damage mechanism, and measures out displacement-life curve of apron.