ABSTRACT
The effect of constraint on the void configuration and coalescence are investigated experimentally using the 3-dimensional fracture surface observations u the using SEM (Scanning Electron Microscope) and 3-dimensional image analyzer. The constraint effect is analyzed by changing specimen shape. The SiC particle reinforced Al 2025 aluminum alloy composite is used to test the ductile fracture by nucleation, growth and coalescence of micro voids under the different structure of materials and the different constraint conditions. The experimental results show that the void aspect ratio is decreased with increases of SiC particle volume fraction in aluminum alloy. The final void volume fraction at fracture also change by the specimen shape and the material’s structure. The effect of the local constraint effect is analyzed by using the axi-symmetric and 3-dimensional FEM analysis. The results show that the fracture process of the notched tensile bar is simulated well and the phenomena agree with the experimental one qualitatively.
