Design of Variable Stress Fatigue Strength for Mechanical Parts of Gun Equipment

For a long time, the design method of static strength design verification and improvement of static strength safety factor used in gun equipment has not been conducive to the improvement of equipment lightweight level, nor can it directly reflect the service life parameters of the equipment. The dynamic response of gun equipment under excitation such as heavy torque, swaying or bumping inertia force, recoil resistance, and inertia force of the follow-up gun reflects the typical characteristics of time-varying stress. It is necessary to use the variable stress fatigue strength of number of coupled stress cycles, which is the service life, for design. Especially for large-mass electromagnetic guns, where three types of cyclic stress exist simultaneously under excitation such as recoil resistance, only by ensuring that the structural fatigue strength safety factor meets the basic requirements can lightweight design be truly carried out. At present, finite element simulation analysis based on fully flexible body modeling has become popular. Combining variable stress test data from shooting experiments, carrying out the design of variable stress fatigue strength for gun equipment is of great significance in promoting the improvement of equipment lightweight level and the friendliness of installation elements.