Random Vibration Fatigue Life Analysis Of Certain Weapon Equipment In Railway Transportation

Weapons and equipment in our country must be transported to reach designated locations for use.Weapons and equipment can be transported by railway,highway,waterway,and air.Random vibrations caused by track irregularities during transportation can cause varying degrees of damage to the structure,and even it will cause the weapon equipment to be unable to be used normally,so it is very important to study the influence of random vibration on the fatigue life of the structure.The research goal of this paper is to evaluate whether the fatigue life of a certain type of weapon and equipment under random vibration meets the life requirements when it is transported by rail and road,and to give a structural improvement plan and recommended materials.The main work is as follows:(1)Carry out rotating bending fatigue test,tensile test,scanning electron microscope observation test and metallographic preparation test on the two magnesium alloys used in this type of weapon equipment,and obtain the tensile strength and yield strength ratio of 2#Mg alloy material 1#Mg alloy materials are 70 MPa and 40 MPa high respectively,and the average elongation after fracture is 3.7 times that of 1#Mg alloy material.The fracture morphology of the two magnesium alloys was observed by scanning electron microscope,combined with the metallographic structure of the two,the study was compared The reasons for the difference in mechanical properties and fatigue properties of the two magnesium alloys.(2)Random vibration analysis is carried out on railway transportation(packing box transportation).The overall stress level of the cabin is low,and the dangerous point appears at the root of the rounded corner of the front support frame of the rear cabin;when the rear cabin is made of 2#Mg alloy material,The service life is about 1.2×10~5times that when the rear cabin is made of 1#Mg alloy material;after comparing with the standard service life,it is found that the rear cabin meets the life requirements when the rear cabin is made of two magnesium alloys.(3)Carry out random vibration analysis on two working conditions of road transportation(motorized transportation).Under the condition of motorized transportation highway,the overall stress level of the cabin is not high,and the dangerous point appears at the root of the rounded corner of the rear support frame.The specific location It is the contact surface between the fillet and the bulkhead;when the rear cabin is made of 2#Mg alloy material,the service life is about 2.6×10~4times that when the rear cabin is made of 1#Mg alloy material.Under highway conditions,the rear cabin uses two kinds of magnesium alloys.The corresponding life spans meet the requirements;under the mobile transportation field conditions,the overall stress level of the cabin is relatively high;the dangerous point is the same as that under highway conditions.When the rear cabin is made of 2#Mg alloy material,the life expectancy is about 3.72×10~2times while the alloy material is 1#Mg.After comparing with the standard life,under the field conditions,the 1#Mg alloy material used in the rear compartment does not meet the life requirements,and the 2#Mg alloy material meets the life requirements.Through the analysis of two transportation conditions,a structural improvement plan is given,and 2#Mg alloy material is recommended as the rear cabin material.