Numerical investigation on composite laminates under double-position low-velocity impacts

Abstract

The dynamic mechanical behaviors of the [Formula: see text] fiber-reinforced composite laminates subjected to double-position low-velocity impacts are investigated by finite element method. Two impact positions symmetrical about the center of the laminates are impacted sequentially with three impact distances (10 mm, 20 mm, and 40 mm) under three impact energies (5 J, 10 J, and 20 J) to study the interference effect of impact damage. For comparison, plastic damage model (PDM) and elastic damage model (EDM) are established to describe the intra-laminar constitutive, respectively. Compared with available experimental data, the mechanical responses calculated by PDM are more accurate, especially at high energies. Affected by the impact interference, the oscillation of force-time curve for the second impact rather than the first impact is relatively weaker, while the severity of impact damage is reversed. The results show that the maximum displacement is more suitable for characterizing the degree of damage interference than bending stiffness, peak force, and energy dissipation.

Experimental and Numerical Study of the Influence of Pre-Existing Impact Damage on the Low-Velocity Impact Response of CFRP Panels

“…Figure 9a compares the force-time responses for impact at S 1 , showing significant changes in the impact response of the pristine specimen compared to the specimen with pre-existing damage. The higher peak force and maximum impact displacement for the repeated impact in Figure 9b were also reported in [26,37]. Figure 9c shows that the interference of the damaged area from the first and second impact significantly reduces the energy absorption of the specimen [26].…”

“…For impacts with interfering damaged areas, lower energy absorption was observed in the second impact, while the opposite phenomenon was observed for non-interfering damaged areas. More recently, Huang et al [37] showed that for repeated impacts at different locations, the maximum displacement better characterizes the damage interference compared to the bending stiffness.…”