Hydrogen pressure at blister initiation of a peroxide-crosslinked EPDM composite (NFT) was successfully estimated in terms of fracture mechanics in the previous study. In that estimation, threshold tearing energy of a static crack Tth in air room temperature was employed as the resistance of the blister initiation. In this study, static crack growth tests of a sulfur-crosslinked EPDM composite (NF) were conducted using single edge crack specimens in air and in 0.7MPa hydrogen gas at room temperature ; then the influence of the type of vulcanizing agents (peroxide and sulfur) and hydrogen exposure on static crack growth properties and threshold tearing energy was investigated. From the observation of static crack growth by optical and secondary electron microscopes, NF had a rougher fracture surface than NFT ; consequently, the static crack rate of NF was slower than that of NFT at the same tearing energy. The Tth value of NF was also about three times higher than that of NFT. Hydrogen did not influence the tendency of the da/dt-T curves and Tth values of NF and NFT.
|Number of pages
|Nihon Kikai Gakkai Ronbunshu, A Hen/Transactions of the Japan Society of Mechanical Engineers, Part A
|Published - Nov 2009
All Science Journal Classification (ASJC) codes
- General Materials Science
- Mechanics of Materials
- Mechanical Engineering