The golden rule of armor development has always been to stay a step ahead of weapon designs, and while most histories focus on the development of weapons, the history of body armor plates and technological developments like tempered steel and Kevlar can be just as interesting.
Medieval Armor
The original weapons were simply enhanced clubs, and the first body armor was essentially heavy, protective leather and some metal chaining. This armor was fairly effective, so better weapons had to be designed to penetrate it. Enter the first edged weapons. Better armor plating developed in response then resulted in advances in projectiles, like arrows, that could use mechanical force to penetrate the metal plate.
Early Modern Armor
When projectiles moved from arrows to musket balls, soldiers naturally looked for some way to protect themselves. Initially, they fell back on the same sort of plate armor that medieval soldiers had worn, but this proved to be useless. Tempered steel improved matters a bit, but the most useful design turned out to be a double layer of metal plate. The outer layer was harder and designed to absorb the musket ball’s energy. The inner layer was softer and slowed the ball to keep it from penetrating the wearer. This same design idea is still used in today’s bulletproof body armor, and body armor for police and soldier alike still uses tempered steel, woven fabrics, and layering to counteract the force and penetration of modern bullets.
The 19th Century
Throughout the 1800s as bullets developed so did interest in body armor. Unfortunately, most of these were ineffective, though the most famous person to try making their own armor was Ned Kelly, an outlaw in Australia known as the Iron Outlaw because he built his own forge to make tempered steel and metal plate armor. His armor could stop bullets of the day at ten paces, but it was so heavy that Ned Kelly’s gang had to take extra horses with them everywhere just to carry it, and taking it on and off was very time-consuming. Wearing it also made it hard for a person to accurately fire a gun.
World Wars
THe advent of enormous wars spurred the deveopment of body armor, though in World War I the art was too primitive to be of much use. The armor that could be designed at the time was so heavy as to be impractical, and so expensive that armies couldn’t afford it. Just about the only soldiers who wore any were German machine gunners. Their armor did stop small arms fire, but it also meant they could not move. The lessons of World War I prompted military minds to consider how to make effective armor that a person could wear and still move in. The first real useful modern body armor was developed by the British for anti-aircraft and naval gunners. The United States began making tactical body armor out of a type of fiberglass laminate. After the war, Smith and Wesson developed their first ballistic body armor for police officers. It was made from tempered steel plates and quilted nylon.
The Kevlar Revolution
A researcher for Dupont names Stephanie Kwolek was experimenting one day with liquid polymers and developed a material of extraordinary stiffness and strength. This came to be called Kevlar, and when it was woven and layered it was found to be up to five times the strength of tempered steel, but far lighter and more flexible. In the middle of the 1970s, the National Institute of Justice began to test Kevlar for use in police safety gear. The Kevlar vest proved to be very effective, saving the lives of thousands of police officers within a few decades.
Modern Advances
Kevlar is still the basis of most body armor, but tempered steel is still used to reinforce and strengthen the highest grades of body armor. There is still ongoing research into the compromise between flexibility, which law enforcement officers and soldiers need, and protection. Since the development of Kevlar, many companies are hunting for even more lightweight and flexible materials, some of which offer real possibilities for the future of protective police duty gear.