honeycomb texture carbon aramid mixed hexagon fabric

honeycomb texture carbon aramid mixed hexagon fabric and aramid fiber's usage

Aramid fiber was the first organic fiber used as reinforcement in advanced compositeswith high enough tensile modulus and strength. They have much better mechanicalproperties than steel and glass fibers on an equal weight basis. Aramid fibers are inher-ently heat- and flame-resistant, which maintain these properties at high temperatures.The term “aramid” is designated for the fibers of the aromatic polyamide type inwhich at least 85% of the amide bonds (dCOdNHd) are attached directly to twoaromatic rings, as defined by the US Federal Trade Commission. The configuration ofthese bonds as either para or meta is often used to classify the polymer.The substitution of the aliphatic carbon backbone by aromatic groups brings aboutconsiderable changes in the properties of the resultant fibers. The first fiber of thisclass to be developed was Nomex from DuPont that appeared in the 1960s. This yarnis of only medium tenacity but is nonflammable and widely used for the production offireproof clothing, electric insulation, etc. However, only a few years later, aramidfibers (Kevlar by DuPont also) with chains containing p-disubstituted benzene ringsappeared. In addition to good thermal stability, these fibers also possess outstandingmechanical properties. Their outstanding potential is derived mostly from the anisot-ropy of their superimposed substructures presenting fibrillar, pleated, crystalline.