Editing Armor (section)

== Modern Materials ==
For soft armor vests, the original materials used to make the dozens of layers that catch bullets and absorb their energy were either silk, cotton, or nylon. Ultimately, they were replaced with high strength synthetic polymer fibers with Kevlar being the first invented in the the 1970's and replaced ballistic nylon. It's been competing ever since with over a dozen rival polymer formulas.
The standard hard armor trifecta of UHMWPE (essentially dense polymers ratched up to 11), Steel/titanium, and Ceramic usually places Ceramic at the top with the latter being first used on helicopter crews in the 1970's as well. As ceramic is not vulnerable to steel-core or fast-moving threats, it does not fold to M855 and M193 at the NIJ III level like UHMWPE and Steel do, respectively. What makes metals and UHMWPE appealing for plate inserts over ceramic is cost reduction and (assuming the plates haven't been penetrated yet) reusability. On the other hand, metal plate inserts need to be coated with high strength resins and polymer covers to prevent metal fragments from ricochets and spalling from hitting soldiers in the face or limbs.