Hey guys, we are trying to make a helmet with new design adding Innegra HMPP material to replace layer of glass, unfortunately, the test is failed, especially for impact according to DOT standard. our peak enegry is 499 on 0/40 impacting point while standards is no more than 400. Any factors that will probably cause such failure? thanks guys for leaving your suggestions and ideas on my thread!
Is this the only test you have done, or are you passing an original design, and trying to modify it? I would think the Innegra would dissipate energy by distributing it through the ply. Is it debonding? I’m sure Innegra sorted that out, but PP is not easily bonded to.
Hey Riff, thanks. we have passed with original design, and try to figure out a new design with Innegra, all look that there is no bonding issue with innegra but not easy to laminate. My analysis at the beginning was that it may happened due to poor bonding issue for innegra with other fibers. However, it seems not like this, all lay-up schedule is fine. That is why i am confused. Only failed at 0/40 impact points, any suggestions?
Could you put up any info about the test standard? not sure what 0/40 is just
I would think that the PP would absorb more energy, but I’m not sure. :-/