You should be able to find material specifications for the resin which indicate the expected water absorption %. There will always be some swell, but these materials can perform well in submerged service. Mechanical properties, including compressive strength, can be approximated by incorporating the properties of each of the matrix and fiber reinforcement materials in an average weighted according to their respective volume fractions in the completed composite. This will be true of random and quasi-isotropic layups. Non-isotropic layups will introduce some dependency on fiber orientation and subsequent layer rotations.<br>As far as water penetration, in a submerged composite I would try not to expose fiber / matrix interfaces to the medium (i.e. cut surfaces or exposed fibers), instead taking care to seal any such interfaces by coating with additional epoxy.<br><br>Sean<br><br><br><br><br>-------- Original Message --------<br>On May 9, 2018, 14:28, hank pronk via Personal_Submersibles < personal_submersibles@psubs.org> wrote:<blockquote class="protonmail_quote"><br><html><head></head><body><div style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:13px;"><div></div>
<div>Emile, </div><div>Can't you test a sample piece? </div><div>Hank</div><div><br></div>
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On Wednesday, May 9, 2018, 11:34:59 AM MDT, emile via Personal_Submersibles <personal_submersibles@psubs.org> wrote:
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<div><div id="yiv3187631827"><div><div class="yiv3187631827WordSection1"><p class="yiv3187631827MsoNormal"><span style="font-family:"Arial", "sans-serif";">Hi All, </span></p><p class="yiv3187631827MsoNormal"><span style="font-family:"Arial", "sans-serif";"> </span></p><p class="yiv3187631827MsoNormal"><span style="font-family:"Arial", "sans-serif";">Material question:</span></p><p class="yiv3187631827MsoNormal"><span lang="EN-US" style="font-family:"Arial", "sans-serif";">Can prefabricated epoxy/glassfibre plate material (like PCB) withstand 5000M / 18.000Ft presurised water? </span></p><p class="yiv3187631827MsoNormal"><span lang="EN-US" style="font-family:"Arial", "sans-serif";">Or will it be impregnated after a while?</span></p><p class="yiv3187631827MsoNormal"><span lang="EN-US" style="font-family:"Arial", "sans-serif";"> </span></p><p class="yiv3187631827MsoNormal"><span lang="EN-US" style="font-family:"Arial", "sans-serif";">Thanks in advance</span></p><p class="yiv3187631827MsoNormal"><span lang="EN-US" style="font-family:"Arial", "sans-serif";"> </span></p><p class="yiv3187631827MsoNormal"><span style="font-family:"Arial", "sans-serif";">met vriendelijke groet, with best regards</span></p><p class="yiv3187631827MsoNormal"><span style="font-family:"Arial", "sans-serif";"> </span></p><p class="yiv3187631827MsoNormal"><span style="font-family:"Arial", "sans-serif";">Emile D.L. van Essen</span></p><p class="yiv3187631827MsoNormal"> </p></div></div></div>_______________________________________________<br>Personal_Submersibles mailing list<br><a ymailto="mailto:Personal_Submersibles@psubs.org" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br><a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br></div>
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