Experimental investigation on the essential work of mixed-mode fracture of PC/ABS alloy

The mixed-mode fracture of polycarbonate (PC)/acrylonitrile-butadiene-styrene (ABS) alloy is experimentally investigated in this work. The essential work of fracture method is employed to measure the mixed-mode fracture toughness of PC/ABS alloy. Results show that the essential fracture work w_e increases significantly with the decrease in loading angles. Crack initiation angles are measured on the fractured specimens. The deviation of crack growth direction from the initial crack plane also increases with the decrease in loading angles, which corresponds to the increase of shear components. Microfracture processes of PC/ABS alloy with different loading angles are examined in situ by a scanning electron microscope. Crazing structures are clearly seen around the crack tip. The appearance, growth, and coalescence of crazes can be observed in the microfracture processes, and the macrocrack propagation direction is finally determined by the coalesced direction of crazes.