Tensile Deformation and Fracture Behavior of AA5052 Aluminum Alloy under Different Strain Rates

To study the mechanical behavior of 5052 aluminum alloy at different strain rates, uniaxial tensile tests at quasi-static, medium, and high strain rates were carried out using a CMT5305 MTS hydraulic servo universal testing machine, Zwick HTM5020 high-speed tensile testing machine, and Split Hopkinson tensile bar device, and the stress-strain curves of the material were obtained. Then, the fracture morphology and microstructure of the samples were studied and analyzed using macroscopic and microscopic analysis methods to obtain the material’s fracture and deformation mechanism. The results show that 5052 aluminum alloy exhibits strain rate sensitivity, and its yield strength and strength limit increase with the increase in strain rate. At different strain rates, the forming properties of the materials are similar. The plastic deformation mechanism is all dislocation slip, and the fracture mechanism is all ductile fracture. However, with the increase in strain rate, the necking phenomenon becomes more remarkable, the dislocation density increases continuously, and the distribution becomes more uniform. The dimples on fracture surface became deeper, and the number of dimples increased, indicating that the plastic deformation of the material increases continuously.