Effect of Different Cryogenic Rolling Strains on the Impact Properties of 6082 Aluminum Alloy

The demand for light-weight materials, exhibiting superior strength and higher toughness, has increased attention to cryogenic temperature rolling as it produces bi-modal microstructures with improved mechanical properties. The samples were cryorolled to a final thickness of 1 mm after thickness reductions of 50%, 66.66%, 75%, and 80%. The ballistic behavior of cryorolled AA 6082 aluminum alloy with different rolling strains/thickness reductions was investigated in this study. The cryorolled Al alloys were subjected to normal high-speed impact using dome-shaped projectiles at velocities between 50 and 250 m/s. The 66.66% thickness reduced samples exhibited higher impact resistance, especially at higher impact velocities. The maximum energy absorption of 106.43 J was observed for 66.66% thickness reduced sample at an impact velocity of 234.38 m/s. This study suggests the existence of an optimal value of cryogenic rolling strain for superior impact resistance, possibly due to an ideal combination of coarse and fine grains in the resulting bimodal microstructure.