The Charpy impact value of plastics is greatly influenced by the notch shape of test specimens. And there exists a close correlation between the Charpy impact value and the appearance of the fracture surface. In this paper, the relation between the notch shape and the appearance of the fracture surface of rigid PVC plates was studied.
The results obtained are summarized as follows:
(1) The fracture of the Charpy impact test specimens did not originate from the surface of notch root, but starts from the inside below the notch root.
(2) The distance between the notch root and the fracture origin increased with the radius of notch root, but it was not affected by the notch depth.
(3) In the case of U notch (r=1.0mm, d=2.0mm), the surrounding neighborhood of the fracture origin formed a sphere-like or disk-like void of about 50μm in diameter.
