Simulation Study On Fatigue Characteristics Of Multifunctional Aluminum Honeycomb Sandwich Structure

Achieving low-cost,miniaturization and lightweight of spacecraft is one of the strategic objectives of space technology in the 21 st century.Specifically,it is to reduce the cost,volume and quality of the spacecraft on the basis of the current level of another order of magnitude,so that the level of China's space technology can be improved qualitatively.Multifunctional structure technology combines multiple functions,which can greatly cut down the mass and volume of the whole system.In aerospace,mass and volume determine the cost of a task.Therefore,the multi-functional structure technology is especially suitable for the aerospace field.The multi-functional structure is a structure with two or more functions,namely,changing the present situation that the structure only can be used to carry,increasing the new functions of the structure,and fully excavating the potential of the structure.At present,most multi-functional structures are designed on the basis of honeycomb sandwich structure.However,there are still many mechanical problems regarding the honeycomb sandwich structure which have not been solved,especially the durability,mechanical response and fatigue characteristics of the honeycomb structure containing core defects,and so on have not been found out,which are the burning difficulties and dangers of new multi-function cellular sandwich structure to be solved in the engineering.This paper regarding complete and containing core defects of aluminum honeycomb sandwich structure as the research object,first of all,using the Electro-mechanical Universal Testing Machine on the room temperature to do tensile,compression and three point bending mechanical properties experiment,by comparing the experimental results,researched the influence of core defect on static characteristics of aluminum honeycomb sandwich structure.Then,the experimental results of tensile,compression and three-point bending mechanical properties were compared with the corresponding simulation results in ANSYS.The finite element model was modified.After that,the ANSYS software was used to simulate the fatigue characteristics of the complete honeycomb structure and the honeycomb structure with the core defects in three kinds of working conditions,which are stretching,compression and three point bending.The fatigue life data under different load ratios were obtained,and the relationship curves between two kinds of structural load levels and fatigue life were fitted.The general law of the fatigue life of two kinds of structures were obtained.Furthermore,by comparing,the influence of core defect on fatigue properties of aluminum honeycomb sandwich structure was analyze.Based on this,the design and fatigue simulation of multi-functional aluminum honeycomb sandwich structure have been completed.In view of the complete aluminum honeycomb structure and the aluminum honeycomb structure with core defects,I put forward a new method of fatigue property research,namely firstly doing the structure statics experiments,then using finite element software to carry on the corresponding static simulation,and modifying the corresponding finite element model according to the results of the statics experiment,finally on the basis of the accurate finite element model,carrying out the fatigue simulation analysis of the structure in order to obtain the fatigue characteristics of the structure,which has certain engineering significance.At the end of the paper,the related research contents of the future multi-functional structure were fully prospected.