Dynamic Test And Numerical Simulation Of Warhead Extrusion Process

The process of bullet engraving is that the gas generated by gunpowder combustion pushes the bullet into the rifling gradually until the groove carved by the rifling is closely matched with the rifling.The process of bullet engraving has a great influence on barrel life,shooting accuracy and launching safety.In this paper,based on the research background of barrel life,the high-precision dynamic test of the bullet engraving force in the process of real shooting is designed and carried out.At the same time,through numerical simulation,the influence law of different internal structure of barrel on the force of bullet engraving process is analyzed.In this paper,firstly,the research status of the engraving process at home and abroad is described.The dynamic testing principle of the process of bullet engraving is studied.The dynamic testing system of the bullet engraving force of a small caliber rifle is improved,and the engraving resistance in the process of bullet engraving is obtained through the test.According to the transient process of bullet engraving,the finite element simulation model is established,and the mechanism of bullet engraving process is analyzed.The change law of the engraving resistance during the dynamic engraving process of the bullet is obtained.The reliability of the model is verified by comparing the test measurement data with the simulation results,and the error between the test measurement results and the simulation calculation results is analyzed.Based on the verified finite element simulation model,the influence of different mesh densities of the forcing cone rifling land on the process of the bullet engraving is studied.In order to study the influence of different internal structure of barrel on the process of bullet engraving,the internal structure of barrel is changed,including the type of rifling,forcing cone angle,depth of rifling,the width of the rifling groove and wrapping angle of rifling.The law of the change of the force on the barrel during the process of the bullet engraving is that the force on the barrel is the least during the process of the bullet engraving into the round rifled barrel,and the force on the barrel decreases with the decrease of the forcing cone angle,the decrease of the depth of the rifling,the increase of the width of the rifling groove and the increase of the rifling twist.The results provide the basis for further study on the technology of long life of barrel.