What is a Prepreg in Composites?

A Prepreg is a material that has been applied to the surface of aerospace composite to improve its properties. A prepreg is typically made from glass, carbon, or aramid fibers and is coated with thermoset resin for additional strength. It usually has an adhesive on one side, making it easier to apply when prepping aerospace composites.



Why Are Prepregs Used?

Prepregs are used in aerospace engineering because they are lightweight, strong, and durable, making them ideal in aerospace applications where weight is often at a premium.


Prepregs are also applied to aerospace composites to enhance their durability. They have an adhesive on one side, making it easier for aerospace engineers to use than other composite materials.


Prepreg manufacturing has become easier over time, with aerospace composites providing engineers with a faster production timeline than metal or plastic alternatives.

Manufacturing of Prepregs

The most commonly used methods for manufacturing prepregs are:

  1. Solvent Drip Process

Prepregs are made by dipping fabric into a pre-determined resin. The next step is to wrap the fabric around an object which gives it its shape. For example, if you were working with a wing component, the fabric cloth is wrapped around it and repeated until the desired quantity is reached.

To enhance their properties, some prepregs are also subjected to vacuum treatment using pressure chambers before, during, or after curing.

  1. Hot Melt Process

Another way to manufacture prepregs is the hot-melt process. This process starts by spreading resin onto a metal sheet; this sheet is then heated up in an oven, melting the resin. The fabric is then laid over the metal sheet and pressed into it.

As the fabric cools, it will have absorbed resin from having been sandwiched between the two. The more pressure you apply during this procedure, the more resins are absorbed by your composite material. Once cooled – often in an oven – your composite material is ready for use.


Advantages of Prepregs Over Other Materials

Aerospace engineering is a demanding profession that requires using lightweight material without compromising on strength. Prepregs are used to quickly create aerospace components that are lightweight, strong, and safe for passenger safety.

Prepreg composites are a great alternative to metal aerospace components in aerospace engineering. They provide several advantages over other counterparts such as:

  • High strength-to-weight ratio
  • Low cost compared to steel or aluminum
  • Rapid production time
  • Good resistance to corrosion, abrasion, and damage from chemicals or solvents.


Why Do You Need Prepregs?

Prepregs provide a lightweight and robust alternative to other composite materials used in the aerospace industry. They are also more convenient to apply than other composite materials because of their adhesive side. You can make an entire aerospace component without any additional prep work. The soft fabrics are easy to cut, shape, and bend – giving you more freedom with your design.

Prepregs are also environmentally-friendly and are disposed of in landfills containing low levels of toxic chemicals, so they pose no risk if released into the environment.


Why Choose PAC As Your Prepreg Supplier

Pacific Aerospace Corp (PAC) is one of the leading suppliers of composite materials in North America. We work with clients across different industries, including aerospace, to provide the highest quality composite materials for your production needs.

Get in touch with us today to discuss how PAC can help you with your composite material needs.