Punch Shear Behavior of Composites at Low and High Rates

A quasi-static penetration model of ballistic penetration of thick section composites is proposed. Quasi-static punch shear tests (QS-PST) and ballistic punch shear tests (B-PST) are conducted to identify five different phases of ballistic penetration, i.e., i) impact-contact, ii) hydrostatic compression, iii) compression-shear, iv) tension-shear, and v) structural vibration. It is well known that the energy absorption in QS-PST is much lower than the B-PST e.g., Mines et al [

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]; and the physics of ballistic penetration is difficult to model with quasi-static models. In order to bridge the gap between QS-PST and B-PST energy absorption, conservation of momentum and energy principles is used to predict the rest kinetic energy of the projectile-laminate system in case of a partial penetrating projectile. Combining the QS-Penetration model and the analytical rest kinetic energy model, a good prediction of ballistic energy absorption is obtained.

FIGURE 1.

Quasi-Static Punch Shear Test: Load-Deflection and Damage.