On the ballistic perforation performance of additively manufactured 316 L stainless steel cylindrical projectiles

The applications of structures made through additive manufacturing (AM) have recently received much attention. In this study, 316 L stainless steel (SS316L) blanks with different dimensions were printed and machined into material specimens and projectiles. Then, metallurgical investigations were conducted to study the microstructures of the as-built AM SS316L samples. Uniaxial tensile and dynamic compression tests were conducted to study the mechanical behaviors of AM SS316L in the material deposition direction. Next, a ballistic test was performed to determine the ability of AM cylindrical blunt projectiles to penetrate Weldox 460E steel plates. The results of the microstructure analysis of the remnants were examined, and the mechanism of microcrack formation in a molten pool was revealed. The results indicate that the molten pool structures may be a key factor affecting the ballistic performance of AM projectiles. For comparison, the tests described above were repeated on traditional cold-rolled (CR) SS316L materials. The ballistic test results show that the ballistic limit velocity of AM projectiles is 8.8% higher than that of CR projectiles, implying no significant decrease in ballistic performance for AM projectiles from an offensive view. Finally, based on a modified Johnson-Cook model, a numerical simulation was implemented in LS-DYNA. The numerical results are in good agreement with the experimental results. This research provides a reference for the application of AM materials in ballistic perforation.