Fiber reinforced plastic (FRP) is quickly gaining popularity in markets that are looking for an alternative to steel. The US estimates the demand to reach 4.3 billion pounds in 2017 and it’s not surprising with such a versatile product. Many industries such as aerospace, military, and construction have great use of FRP for its strength, light weight, and resistance to the elements.
FRP comes in several forms. Many different fiber reinforcements are available including glass, carbon, basalt and aramid. These fibers can be woven, stitched, or braided to provide increased stiffness and tensile capacity while the resin binds the fibers into a firm matrix. Fillers and additives are used to not only help reduce cost of producing fiber reinforced plastic, but they also work to reduce shrinkage and improve mechanical and physical properties.
How do fiber reinforced plastics stand up against steel? These composites have many excellent structural qualities including high strength, fatigue endurance, and high resistance to elevated temperature, abrasion, corrosion, and chemicals. Reinforce materials also weigh only 1/3 as much as steel and, because of its light weight, it is easier to transport and handle during construction, cutting down on project time. FRP actually maintains similar and sometimes better tolerances and material strengths than steel or aluminum.
Here are three industries where FRPs are making a big difference:
1. Construction Industry
Currently, FRP is most widely used for bridge superstructures and bridge deck. The very first FRP constructed bridge erected in the US was in Russell, Kansas in 1996. It took the work crew only one day to install the superstructure due to the material’s light weight. In 2005, the historic Broadway Bridge in Portland, Oregon (pictured right) was renovated to replace the steel grating deck with a solid FRP one, which could provide better traction when wet and would also be more resistant to corrosion than the metal. FRP is used to strengthen and reinforce existing beams and columns of buildings. FRP is also extensively used for safety applications such as hand railings. The only downside to using fiber reinforced polymers seems to be a higher initial cost, though it balances out from a lower projected lifecycle cost of maintenance and repairs.
2. Automotive Industry
FRP is also popping up more and more in the automotive industry. Carbon fibers were once used exclusively in race cars but BMW has introduced the i3, which represents the first effort to mass produce a car made largely of carbon fiber. While the material made the car lighter – enabling it to go faster than the best-selling electric car – the light weight also makes the car more fuel-efficient and has the potential to reduce greenhouse gasses and other emissions if the carbon fiber trend takes off. The downside is (again) the high cost, waste disposal – the material cannot be reused from one car to build another – and repair. BMW’s initial costs to set up a fiber reinforced plastic factory that could provide a consistent supply of the material were formidable. When steel is impacted it bends and deforms but carbon fibers disintegrate. This makes for a very efficient energy dissipation mechanism but when the material breaks and the fibers disintegrate it can cause unpredictable results.
3. Aerospace Industry
Aircraft manufacturers are also reaping the benefits of this powerhouse material. The Boeing 787 makes greater use of fiber reinforced plastic materials in its airframe and primary structure than previous commercial airplanes, offering 20% weight savings on average compared to more conventional aluminum designs. Composite materials allow for the construction of a lighter, simpler structure, which increases airplane efficiency, reduces fuel consumption and reduces maintenance. Additionally, the 787’s unique one-piece composite barrel construction results in the elimination of longitudinal skin splices that reduces not only weight and drag but also significantly reduces the amount of maintenance required because there aren’t additional joints, fasteners or splice plates.
Overall, fiber reinforced polymers are really making a name for themselves due to their high stiffness to weight ratio, high strength, and resistance to corrosion, fatigue, and chemicals.
Do you have experience working with fiber reinforced polymer composites? Please share in the comments section below!
Looking for more information about FRPs? Check out our Guide to High Strength Engineering Plastics.