| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1577573 | Materials Science and Engineering: A | 2012 | 5 Pages |
Residual microstructure associated with the crater in 15% Ti–6Al–4V wire mesh reinforced 5A06 alloy (TC4m/5A06) composite thin target impacted by Al projectile with the speed of 2.5 km/s were investigated. The depth and diameter of crater impacted by Al projectile with the diameter of 1.6 mm are 1.62 mm and 2.8 mm, respectively. At the back face, bulge with height of 0.5 mm is produced along the impact direction and cross-shaped cracks and spalling form at the top of the bulge. With projectile diameter increasing to 2 mm, composite gets perforated and the diameter of perforation becomes 3.2 mm. Microstructured observation of crater impacted by Al projectile with the diameter of 1.6 mm shows that in the region near the pithead and around the center of crater, decohesion occurs at the interface between TC4 wire and Al matrix and the direction of decohesion is in agreement with the outline of crater. In the region at the bottom of the crater, there appears an adiabatic shear band (ASB) in a TC4 wire and two sections of wire slide with each other along the direction of ASB with a distance of 200 μm. TEM observation reveals that block-shaped Ti2Al phase with size up to 1 μm forms in the ASB at the bottom of the crater after high speed impact. Besides, amorphous structure, nanograins and ultrafine grains are found in Al matrix at the bottom of the crater.
► At the back face of crater, bulge and cross-shaped cracks and spalling are formed. ► Near the pithead or middle of crater, decohesion occurs at the TC4–Al interface. ► At the bottom of crater, there appears an ASB in a TC4 fiber. ► Block-shaped Ti2Al phase forms in the ASB at the bottom of crater after impact. ► Amorphous structure and nanograins are found in Al matrix at the bottom of crater.
