Introduction and characteristics of carbon fiber prepreg

Introduction and characteristics of carbon fiber prepreg

Prepreg is an intermediate material for making composites by combining the resin with the fibers in advance before curing and keeping a certain storage period, during which the lay-up design and moulding can be carried out at any time. Carbon fiber prepreg is an intermediate composite material processed by carbon fiber filament through spreading yarn (or carbon fiber woven cloth), under pressure and temperature, and resin pre-coated on release paper, and then cooled, laminated, rolled and processed into intermediate product composite material, also called carbon fiber prepreg.

The common components of a prepreg are: a layer of release paper (white) at the bottom, a finished prepreg (black) in the middle, and a layer of polyethylene film (blue) covering the surface, where the finished prepreg in the middle in turn consists of resins and fibers, as shown in the diagram below.

The meaning of prepreg is to pre impregnate the fibers with resin, lay and shape them in the subsequent process, and heat and cure them. So the resin of the prepreg is uncured resin, mainly thermosetting resin. There are many types of thermosetting resins, commonly used including phenolic resin, epoxy resin, bismaleic acid resin, vinyl resin, cyanate resin, etc. Among carbon fiber prepregs, epoxy resin is the most commonly used and widely used, and in some high-temperature resistant situations, bismaleic acid and cyanate resins are used.

Advantages of carbon fiber prepreg material:

1. It has a light specific gravity and a density of generally 1.70-1.80g/cm ^ 3, which is lighter than many metal materials

2. High strength, can reach 1200-7000Mpa, which is 7-10 times that of steel with the same cross-section

3. Good elastic modulus, reaching 200-400Gpa, similar to steel

4.The coefficient of thermal expansion is close to zero and can even be negative (-1.5x10 ^ 6)

5 carbon fiber material not only can resist UV damage, but also has good corrosion resistance,

It can still work normally in harsh and complex environments.

6 carbon fiber materials have obvious advantages over ordinary materials in terms of wear resistance and impact resistance

7. Good permeability and high radiation transmittance

8 carbon fiber material is a conductive material with good conductivity performance