A study on the dynamic shock performance of 7055-T6I4 aluminum alloy based on experimental and simulation

In order to fill up the deficiency of dynamic impact characteristics and damage mechanism of 7055 aluminum alloy. Johnson-Cook constitutive equation and damage model for 7055 aluminum alloy was established. Dynamic impact performance is studied using experimental and simulation methods. Results show that: Under 120 °C, the microstructure of the alloy changed notably after dynamic shock, the number density of η′ precipitated phases reduced appreciably as the shock strain rate increased; Under 220 °C, the number density of the η′ precipitated phases in the testpiece reduced significantly after shock when the strain rate of dynamic shock was 6000s-1; Under 220 °C, as the shock strain rate increased, almost all the η′ precipitated phases turned into a η phase incoherent to the aluminum matrix. At the same time and velocity, the stress after dynamic shock is the largest when the dynamic temperature is 220 °C; when the ambient temperature is 120 °C, the stress after dynamic shock is the smallest, and the stress after dynamic shock at 220 °C is twice as big as that at 120 °C.