Body armor evolved from ancient armor. In World War I, steel cuirasses were used by special forces and a small number of infantry in the United States, Germany, and Italy. In the 20s of the 20th century, the United States developed a bulletproof vest made of steel sheets. In the early 40s, the United States and some countries in Western Europe began to develop body armor made of alloy steel, aluminum alloy, titanium alloy, fiberglass, ceramic, nylon and other materials. In the 60s, the U.S. military used high-strength synthetic aramid fiber (Kevlar fiber) developed by DuPont to make body armor, which has good bulletproof effect, light weight and comfortable wear. At the beginning of the 21st century, the U.S. military used the "Interceptor" body armor with modular design and KM2 high-strength aramid synthetic fiber as the bulletproof layer material on the battlefield in Iraq. Since the end of the 50s of the 20th century, the Chinese People's Liberation Army has successively developed and equipped FRP body armor, high-strength special steel body armor, high-strength high-modulus polyethylene body armor and ceramic body armor. With the development of science and technology, body armor will adopt bulletproof materials with better performance, reduce weight, improve bulletproof effect and wearing comfort, and further realize structural modularization, variety and style serialization.
