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Looking for information on the best combination of materials to use

Looking for information on the best combination of materials to use

Looking for information on the best combination of materials to use

(OP)
Good afternoon!

I'm working on designing composite masks, and am looking for some sources to research some of the newer materials out there and their potential use in my application.  I'll be working out of a small (OK, call it home!) shop, and have been researching the obvious so far; fiberglass, aramids, carbon fiber and some hybrids.  I've seen new materials out there like Dyneema, Spectra among others.

The end product will need to be able to withstand impact from a projectile, while protecting the head of the wearer.  Safety is paramount, but weight is a close second.

Thanks for your assistance.

RE: Looking for information on the best combination of materials to use

So what is your question?
Are you looking for a source of supply, or are you looking for data on UHMW polyethylene fiber ?
B.E.

RE: Looking for information on the best combination of materials to use

I'd say his question is Dyneema, Spectra or similar any better than the materials he has listed having already researched for his application?

RE: Looking for information on the best combination of materials to use

(OP)
Yes, I'm looking for sources for information, and want to research the newer materials to see if they are suitable.  I'm looking for impact absorption, stiffness, fracture points, things like that.

What I'm looking to make is along the lines of a catcher's mask.  It is going to take impacts in much the same way, and I am looking to improve on existing products and design new ones.  The materials I want will be able to withstand these kinds of impacts and protect the wearer, without breaking, and transferring the least amount of stress to the wearer.

I hope this clarifies things.  I'm not necessarily looking for someone to give me the answers, but I would like to know where to find the best information, and what kinds of materials are out there that I might not have mentioned already.

RE: Looking for information on the best combination of materials to use

hroark2112
 UHMW polyethylene fiber,  Dyneema, Spectra,Vectran and about five other brands that I know of, have been around since the 1970's, like the aramid fibers, Kevlar,Technora.  they have good tensile strength They creep in compression Which may be good for something designed to take an impact. Major disadvantages are cost and the fact that they are hard to glue things to. Plasma etching is required to get epoxy and other resins to stick to them.
I hope this will give you a start.
B.E.

RE: Looking for information on the best combination of materials to use

Zylon (PBO) is also used for this sort of thing, and has the highest specific strength of just about any available material. Beware: a few years ago there was an issue with Zylon having residual hydrochloric acid (at least, I think I red that it was hydrochloric) which caused some degradation during storage of bullet resistant vests.

Another promising ballistic fiber is M5, now under development by du Pont.

A bit less high tech is HM PP Innegra. The manufacturer's website http://www.innegrity.com/ has more info these days. For high velocity impacts it looks like Innegra might save some money for a small increase in weight cf. para-aramid, UHMWPE, PBO. The same may be true of ballistic Nylon, with a bit higher weight penalty, at least according to Innegrity.

There is also another high performance organic, PBZT (poly(p-phenylene benzobisthiazole)), but I don't know of any suppliers for that. It sounds a bit experimental.

For the para-aramids, ARMOS, a Russian product, looks interesting, and Kevlar KM2 seems popular for body armor as an alternative to Kevlar 49 or 149. Teijin, who make Twaron para-aramid and Technora (as mentioned by berkshire) para-meta-aramid, might also have a grade tweaked for impact (I assume that that's what du Pont did with Kevlar KM2—there's not that much info on it easily available).
 

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