Orthogonal impact load in 6061-T651 and 7075-T651 aluminum alloy plates

Abstract

Orthogonal impact load in 6061-T651 and 7075-T651 aluminum alloys was evaluated. Clamped square plates with the dimensions of 300 × 300 × 6.35 mm were experimentally impacted at 200, 400 and 600 J with different velocities by means of a drop tower-device. Impacted force-time and -displacement curves were obtained to evaluate the absorbed energy. Also, the impact damage was evaluated in terms of the transverse displacement and overall crack length induced to the plate. Further, explicit finite element and analytical approaches were used to compare against the experimental results. Considering the absorbed energy as a direct function of the induced damage, it was observed that the 7075-T651 alloy had a better performance than 6061-T651 for the 200 J impact test. Even though both alloys had a similar response for the 400 J impact test, it was not the case at 600 J where the absorbed impact energy for the 6061-T651 alloy was higher than for the 7075-T651. The induced damage (crack length) tends to increase with the strain rate for a given impact energy level.