Time-Dependent Crack Growth in PE [PE]

# 1998 Gothenburg

The crack growth rate in HMN 5202 and HXM 50100 polyethylcne has bcen studied as a function of stress intensity using deeply notched three-point bend specimens. l'he load-line displacen~entin response to a static applied load has been measured, with tlie material compliance as a function of time determined from the specimen compliance prior to the initiation of crack growth. Measured specimen compliance as a function of time after crack growth begins is used to determine crack g r o w ~ hrate as a function of stress intensity. The crack growth rate has been shown to be a fi~nctionof stress intensity. giving the same crack growth rate h r very different combinations of load and crack length. tvith excellent repeatability. The experimentally determined crack growth rate as a Cunction of stress intensity has beell compared to theoretical predictions by Willia~nsand Scliapery. This comparison implies that both critical crack tip opening displacement, 6,,, and critical energy rclease rate, G , , increasc with increasing crack q r o ~ t l rate. i The results also show that the crack growth rate is significantly reduced by plane stress conditions at the surface of tlie specimen.

Please note that the whole article content is available on PPCA website onlySource : 1998 Gothenburg

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