고속충돌에 따른 금속재 파편의 분산거동

초록

Damage and fracture occur when a projectile impact on a structure, and the resulting debris may cause secondary damage on the other components located behind the structure. In this study, high velocity impact tests together with numerical analysis were conducted to predict the behavior of the debris dispersion. The high velocity impact tests consist of projectile, target plate and witness plate. Two types of materials namely S45C steel and aluminum were used for the cylindrical projectile (20 mm diameter, 19 mm length) and the target plate (5 mm thickness), respectively and the aluminum (5 mm thickness) plate located 200 mm away from the target plate was used for the witness plate. The projectile impacts on the target plate with a velocity of approximately 1 km/s, and the debris were generated by the impact damages in the witness plate. After the impact, the debris dispersion radius on the witness plate was measured. The debris dispersion radius was largest when the steel projectile impacted on the steel target plate. And the witness plate was hardly damaged when the aluminum projectile impacted on the steel target plate. A numerical analysis was performed in the same conditions with the impact tests. To describe the generation of the debris and the damage on the witness plate, a smoothed particle hydrodynamics (SPH)-finite element (FE) coupled technique was applied in the numerical analysis. The experimental result agreed well with those from the numerical analysis below 5 % error, and it is thus thought that the SPH-FE coupled technique presented in this study is valid and will be sufficiently applicable to the high velocity impact related analysis.

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