Aramid fiber: The basics

Editor’s note: This content was originally published on NetComposites.com. NetComposites was acquired by CompositesWorld’s parent company, Gardner Business Media, in February 2020.

Aramid fiber is a manmade organic polymer (an aromatic polyamide) produced by spinning a solid fiber from a liquid chemical blend. The bright golden yellow filaments produced can have a range of properties, but all have high strength and low density giving very high specific strength. All grades have good resistance to impact, and lower modulus grades are used extensively in ballistic applications. Compressive strength, however, is only similar to that of E-glass.

Although most commonly known under its Dupont trade name “Kevlar,” there are now a number of suppliers of the fiber, most notably Akzo Nobel with “Twaron.” Each supplier offers several grades of aramid with various combinations of modulus and surface finish to suit various applications. As well as the high strength properties, the fibers also offer good resistance to abrasion, and chemical and thermal degradation. However, the fiber can degrade slowly when exposed to ultraviolet light.

Aramid fibers are usually available in the form of rovings, with texes ranging from about 20 to 800. Typically the price of the high modulus type ranges from £15 to £25 per kilogram.

For the latest on aramid fibers, visit compositesworld.com/hashtag/aramidfiber.