Chemistry has allowed humans to create a myriad of new inventions and improve on innumerable existing ones. Through research, we've created synthetic materials that are stronger than the metals we've used for centuries. One synthetic fiber invented in the last several decades is being implemented into many protective gear and vehicles because of its sheer strength and durability. Militaries, law enforcement and civilian industries are using the synthetic fiber called Dyneema to protect lives and equipment.
Dyneema is a high-strength synthetic fiber that is capable of protecting an individual or vehicle from threats like an improvised explosive device (IED) or shots from an AK47 [source: Dyneema ]. If you took a block of Dyneema and block of steel, on a weight-for-weight basis the block of Dyneema would be 15 times stronger than the steel block [source: Dyneema]. The lightweight fiber is strong and moldable, yet it can withstand significant explosions and extreme weather conditions. There are other synthetic fibers similar in characteristics, like Kevlar, but only Dyneema is trademarked as the world's strongest fiber [source: Dyneema].
Dyneema is advantageous to police forces and militaries not only because it's able to withstand extreme conditions and explosions, but also because it's lightweight and can be applied to many kinds of vehicle designs and specifications. Even though Dyneema is being used to help save lives and protect vehicles, it isn't only used in these life-threatening situations. Dyneema is also created for commercial use in the shipping, medical, and metalworking industries as well.
In order to fully appreciate this invention and to understand it's uses in armored vehicles, bullet-resistant vests and other applications we first need to understand a little bit about how it's constructed and why it's so strong.
Read the next page to find out what makes Dyneema the world's strongest fiber.
Characteristics of Dyneema
Dyneema fibers were invented over 20 years ago and by a company called DSM Dyneema and has been in production since 1990. Dyneema fiber is a gel-spun, multi-filament fiber that is created from ultra high molecular weight polyethylene. Polyethylene is a common chemical combination used in many plastics, but Dyneema's is much more than a common plastic. What does this mean to everyone without a chemical engineering degree? It means that the fiber has extreme strength, minimal weight and a large amount of useful applications.
Dyneema's chemical composition allows it to boast of many characteristics such as:
- Resistance to most chemicals
- Low density
- Invisible to ultra-violet light sources and thermal imaging devices
- Floats on water
- Smooth to the touch
- Fire resistant and self-extinguishing
- Can withstand extreme cold and hot temperatures
- Biologically inert (doesn't cause a reaction to the human body)
- Sonic velocity and acoustic impedance near that of water
- High electrical resistance
- Elongation at break is low, energy needed to break is high
- Very high strength
On a weight-for-weight basis, Dyneema is 15 times stronger than steel and is 40 percent stronger than aramid fibers [source: Dyneema]. Aramid fibers are another type of synthetic material that has similar characteristics, although not all; one of the most common types of aramid fiber is Kevlar.
Dyneema can be created as a continuous filament yarn, used for things like strong ropes or nets, or as a unidirectional sheet. The unidirectional sheet is created in layers with one layer placed on top of another at a 90-degree angle to the layer beneath it [source: SoldierMod.com]. This layering allows the fiber to absorb harsh impacts and disperse energy quickly and efficiently to other layers.
On the next page, we'll find out how Dyneema is used to armor vehicles and how it protects occupants during an explosion.
Armored Vehicle Protection
One of Dyneema's main uses is for armored vehicle protection. Its incredible strength and resistance to extreme and changing weather conditions make it an ideal addition to vehicles in dangerous situations. Its ability to be molded to various forms allows Dyneema to be used in a variety of vehicles for military, law enforcement and civilian protection applications. Depending on the type of situations that Dyneema will be used for it can be obtained for either soft ballistics, like handguns, or hard ballistics, like antitank projectiles, land mines.
Dyneema can be used in two different ways for vehicle protection, as either spall liner or as a panel. In its form as spall liner, Dyneema works as an extra layer of protection against a ballistic threat to a vehicle. Spall liner is used to protect vehicle occupants by catching and absorbing the ballistic itself, or metal fragments that came off of the vehicle due to the explosion. When Dyneema is used as panel it can protect against stronger ballistic threats such as antitank projectiles and tank-penetrating projectiles. The panels can be custom shaped and easily cut to the design specifications of the vehicle.
By themselves or combined Dyneema has the potential to protect against a range of ballistic threats including direct gunfire from an AK47, improvised explosive devices (IEDs), rocket-propelled grenades (RPGs), land mines or explosively formed penetrators (EFPs).
Compared to armor plating, armor made with Dyneema that has a steel or ceramic strike plate is 50 to 75 percent less dense than steel armor [source: SoldierMod.com]. Because it is extremely light and moldable a vehicle equipped with Dyneema doesn't have to sacrifice maneuverability or design, or change the center of gravity in order to protect against an explosion or gunfire.
Dyneema has also been implemented into an invention that protects not only the occupants of a vehicle but also the vehicle itself from a direct explosion. The structural blast chimney uses Dyneema to take the initial blast of an explosion and channel it towards the center of the vehicle and then up and away from it. The design of the chimney along with the Dyneema's impact absorption allows the vehicle stay firmly planted on the ground and intact during an explosion, protecting occupants from sound, heat and sheer force of the explosion.
Let's go on to the next page to find out how Dyneema is being used for other areas of life protection, who's using it, and how it's being used in other industries.
Life Protection and Other Uses
Dyneema has other life-saving applications besides armored vehicles. Many bullet-resistant vests, boats and aircraft also use Dyneema. South Korea's navy uses Dyneema in some of its patrol boats and hovercrafts as a way to protect them against fire and ballistic impact. The boat panels are made with Dyneema then covered with a glass epoxy resin. Because Dyneema is buoyant, it not only protects the watercraft but can also be used in marine applications like this.
Dyneema has also been implemented into airplane cockpit doors as a means of bullet resistance. After the September 11 attacks in the United States, the Federal Aviation Administration required that cockpit doors be bullet resistant. Dyneema has been used in cockpit doors ever since and now 85 percent of all aircrafts flying in the United States have cockpit doors made with Dyneema [source: Dyneema Matters].
In addition to vehicle, marine and aircraft protection, Dyneema is also used for bullet-resistant vests and helmets. A joint initiative by the U.S. Army and Marines to increase helmet performance found that Dyneema could increase fragmentation performance for helmets by 35 percent or more [source: Dyneema]. Some Dyneema helmets are also used in tactical police teams like SWAT. The helmets created with hard ballistic resistance from Dyneema are as strong as previous helmets made with other materials, but with half the weight.
Depending on how a bullet-resistant vest is made with Dyneema, it can withstand knives, handgun fire, armor piercing rounds, and even rifle fire from weapons like the AK47. For the 2008 Olympics in Beijing, the Beijing Bureau of Public Safety used bullet-resistant helmets and vests. The U.S. Army has used Dyneema in various applications in both the Iraq and Afghanistan wars for both personal and vehicle protection.
Dyneema isn't just only used to stop bullets and protect against explosions though. It can made into strong ropes for mooring and towing lines in the shipping industry, safety gloves in the metalworking industry, nets for fishing and even for surgical cables and orthopedic sutures in the medical field. Because of its extreme strength and light weight, companies continually work with DSM Dyneema to find new ways to use the fiber.
For more information about Dyneema and other super-strong materials, follow the links on the next page.
More Great Links
- Dyneema.com. (March 1, 2011) http://www.dyneema.com/
- Dyneema.com. "Dyneema Life Protection Press Package." (Feb. 28, 2011) http://www.dyneema.com/en_US/public/dyneema/media/packages/Life_Protection_press_package.zip
- Dyneema.com. "Dyneema Fact Sheet." Jan. 1, 2008. (March 1, 2011) http://www.dyneema.com/en_US/public/dyneema/downloads/Comprehensive_factsheet_UHMWPE.pdf
- SoldierMod.com. "DSM Dyneema: Diverse Protection." (Feb. 28, 2011) http://www.soldiermod.com/summer-08/industry-dsm.html
- Dyneema.com. "Dyneema Matters - Structural Blast Chimney." Feb. 16, 2011. (Feb. 28, 2011) http://www.dyneemamatters.com/german_certified_ballistic_helmet_insert_and_vest_made_with_dyneema_and_reg
- Dyneema Matters - Vehicle Protection. Dyneema Vehicle Protection. (March 1, 2011) http://www.dyneemamatters.com/vehicle_protection_1