Influence of Various Stabilizers in PE on Creep Crack Growth Behavior and Pipe Failure [PE]


Additional Information - Posters # 1998 Gothenburg

In this work differently stabilized Poly(ethylene) (PE)-types were characterized by linearelastic fracture mechanics (LEFM ) (creep crack growth tests) and internal pressure testing. In total, 6 PE formulations (2 polymer types with 3 stabilizer systems) were investigated. While no influence of stabilizer type was found in both polymer types at high crack speeds, significant effects of the added stabilizer type and concentration could be found for very low creep crack growth rates. The experimental data also indicate good agreement between the test results of the two types of tests (i.e., identical material ranking in both tests), thus corroborating the hypothesis, that the brittle or quasi-brittle failure of pressurized pipes can be predicted by a LEFM approach.

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