Behavior Of The Cracks Propagation Exist In A luminum Alloy (AL-7020T6) Under The Effects Of Mixed-Mode Stresses

Abstract

The aluminum alloys using in engineering components and structure mostly contains cracks and subjected to mixed mode (I&II) loading, This study presented theoretical and experimental analysis on the behavior of the crack propagation under the effect mixed mode stresses in the aluminum alloy (AL-7020T6) by using (CTS) specimens connected into steel fixture at different angles and subjected to a monotonic loading at constant rate of displacement . The results showed that , the (LT) specimen have larger fracture toughness than (TL) , Good agreement between theoretical results and results of the ANSYS Software, Mode I fracture toughness larger than mode II this is indicated that the aluminum alloy (AL-7020T6) contain cracks has stronger in tensile and weak under shear loads ,The total energy release rate (Gt) decrease with increasing mode II fraction this is indicated that the crack in the aluminum alloy at mode I need higher energy than mode II in order to growth