Strength simulation analysis on fracture of aluminum lightweight cartridge case

Aluminum lightweight cartridge cases have been increasingly applied in rele-vant fields owing to their dual advantages of weight reduction and adequate mechanical properties; however, their root fracture issue often impairs opera-tional reliability, prompting this study to investigate the root fracture of such cartridge cases. To accurately identify and address the key factors inducing fractures, the research team first performed theoretical analysis to systematically derive the strength characteristics of the cartridge case's axial stress. Subse-quently, using professional finite element analysis software, they established a finite element model of the cartridge case that is consistent with actual working conditions. Simulation calculations were then conducted to obtain the stress distribution of the cartridge case, and the results revealed significant stress con-centration at the cartridge case root—this was in exact agreement with the frac-ture location observed in physical tests, effectively verifying the model's validi-ty. Leveraging this validated model, the team adjusted model parameters to ana-lyze how different friction coefficients and locking gaps affect the cartridge case's axial stress. It was found that a smaller friction coefficient results in lower axial stress of the cartridge case, while the locking gap exerts no significant im-pact on the axial stress. These simulation results can provide a practical refer-ence for the structural optimization design of lightweight cartridge cases, facili-tating the improvement of their overall performance and service life.