Plastic Pipes Conference Association # 1995 Edinburgh
Rose, Channell, Palmer
A series of PE 80 and PE 100 materials have been investigated to determine whether there exists a link between resistance to slow crack growth as measured by notched pipe test and creep of macroscopic oriented samples. Preliminary results suggests that there is a correlation between a single creep parameter and notched pipe failure times. If such a correlation can be fully established the oriented creep test could be used to predict slow crack growth performance. Since the test can be undertaken on small quantities of material in short time scales it could be used to screen materials prior to tests on extruded pipe such as the notched pipe test. The existence of the correlation supports earlier indications that the creep of fibrils spanning a craze zone is a key mechanism controlling slow crack growth.
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