Do you know the difference between carbon fiber and fiberglass? And do you know whether one is better than the other?
Fiberglass is definitely the older of the two materials. Its Created by melting glass and extruding it under high pressure, then combining the resulting strands of material with an epoxy resin to create what is known as fiber-reinforced plastic (FRP).
Carbon fiber consists of carbon atoms bound together in long chains. Thousands of fibers are then combined to form tow (aka strands of bundled fibers). These tows can be woven together to create a fabric or spread flat to create a “Unidirectional” material. At this stage, it is combined with an epoxy resin to manufacture everything from tubing and flat plates to race cars and satellites.
It is interesting to note that raw fiberglass and carbon fiber demonstrate similar handling characteristics and can look similar too if you have a black-dyed fiberglass. It is not until after fabrication that you begin to see what separates the two materials: namely strength, stiffness and to a small extent weight (carbon fiber is slightly lighter than glass fiber). As to whether one is better than the other, the answer is ‘no’. Both materials have their pros and cons depending on the application.
STIFFNESS
Fiberglass tends to be more flexible than carbon fiber and is about 15x less expensive. For applications that don’t require maximum stiffness – like storage tanks, building insulation, protective helmets, and body panels – fiberglass is the preferred material. Fiberglass is also frequently used in high volume applications where low unit cost is a priority.
STRENGTH
Carbon fiber truly shines with respect to its tensile strength. As raw fiber it’s only slightly stronger than fiberglass, but becomes incredibly strong when combined with the right epoxy resins. In fact, carbon fiber is stronger than many metals when fabricated the right way. This is why manufacturers of everything from airplanes to boats are embracing carbon fiber over metal and fiberglass alternatives. Carbon fiber allows for greater tensile strength at a lower weight.
DURABILITY
Where durability is defined as ‘toughness’, fiberglass comes out the clear winner. Though all thermoplastic materials are comparably tough, the ability of fiberglass to stand up to greater punishment is directly related to its flexibility. Carbon fiber is certainly more rigid than fiberglass, but that rigidity also means it is not as durable.
PRICING
The markets for both carbon fiber and fiberglass tubing and sheets have grown dramatically over the years. With that said, fiberglass materials are used in a much broader range of applications, the result being that more fiberglass is manufactured and prices are lower.
Adding to the price difference is the reality that manufacturing carbon fibers is a difficult and time-consuming process. In contrast, extruding melted glass to form fiberglass is comparably easy. As with anything else, the more difficult process is the more expensive one.
At the end of the day, fiberglass tubing is neither better nor worse than its carbon fiber alternative. Both products have applications for which they are superior, its all about finding the right material for your needs.