Static Analysis And Experimental Verification Of Shear Strength Of Aircraft Off Pin

As an important component of the aircraft landing gear,the landing gear has a very important role in the process of landing.Anti crash requirements during the flight due to various factors when the plane crash to ensure personnel safety characteristics of aircraft structure,requirements of aircraft structure damage even to the crew’s safety and security greatly,reduce the damage degree.In order to meet the airworthiness requirements,in the structure of the aircraft main landing gear and wing fuselage joints with emergency break away from the design,according to the relevant provisions of the airworthiness using 15-5PH stainless steel as the material used to break away from the pin and discusses the emergency break away from the requirements of the structure design of the pin.Firstly,About 15-5PH stainless steel specimen tensile experiments,to study the deformation behavior.The tensile stress and strain curves were obtained,and the yield strength and elongation of the material were determined.Based on the tensile test,the final constitutive model is established by means of the plastic deformation stage.The damage theory of the off pin is studied,and the shear fracture damage parameters are determined by the method of simulation analysis.Secondly,from the real structure and pin shear test of the actual situation as the basis to the aircraft,with the help of ABAQUS software build off pin structure model,assembly components defined material properties and surface constraints,choose suitable grid type for different grid size to break away from the pin for finite element analysis,comparison of different analysis results.In choosing the optimal grid size for the quality analysis of zoom coefficient on the calculation result of the 0.6 conditions,analysis showed that the quality of zoom coefficient is set to 100000,saving computation time and ensure the accuracy of the calculation results.The hollow pin design concept as a way to weaken the strength,size of 19 9mm-27 mm from the pin do finite element analysis,in order to meet the requirements to determine the shear strength increases with off the pin diameter for the fracture required to exert maximum load is small.Finally,the shear simulation results are verified by the real test,and the shear test is made by using the metal shear testing machine to meet the requirement of machining design.The test results are in agreement with the simulation results,which shows the rationality of the finite element model.