3 Manufacturing Processes

 

The U.S. F1 complex in Charlotte, N.C., includes an autoclave to create carbon-fiber parts.

3.1 Mold
3.2 PMC (Polymer Matrix Composite) Fabrication Methods.
3.3 MMC (Metal Matrix Composite) Fabrication Methods.
3.4 CMC (Ceramic Matrix Composite) Fabrication Methods.

To fabricate fiber reinforced composite articles it is necessary to impregnate fibers with a
resin or put preimpregnated fibers or molding compound in a mold and, often, apply heat and
pressure. The types of material and forms these take, and manufacturing processes used,
are chosen to give or approach as nearly as possible the required performance in the
finished article, at the minimum cost.

3.1 Mold

Temporary Molds :

Permanent Molds :

Mold Design Parameters :

3.2 PMC Fabrication Methods

Polymer Matrix Composite is a material consisting of a polymer (resin) matrix combined
with a fiber reinforcing dispersed phase. Polymer Matrix Composites are very popular due to their low cost and simple fabrication methods.

Use of non-reinforced polymers as structure materials is limited by low level of their mechanical properties : Tensile Strength of one of the strongest polymers - epoxy resin is 20000 psi (140 MPa). In addition to relatively low strength, polymer materials possess low Impact Resistance.

Advantage :

High tensile strength
High stiffness
Low cost

Disadvantage :

Low thermal resistance
High coefficient of thermal expansion

Reinforcement Materials :

Fiberglass
Carbon Fiber Reinforced Polymer Composites
Kevlar

Reinforcing Fiber Arranged in Different Forms :

Unidirectional fibers;
Rovings;
Veil mat: thin pile of randomly orientated and looped continuous fibers;
Chopped strands: thin pile of randomly orientated and looped short (3-4 inches) fibers;
Woven fabric.

Methods :

1. Hand Lay Up
2. Vacuum bag Molding
3. Pressure Bag Molding

4. Autoclave Molding (The best method.)

5. Spray Up
6. Filament Winding
7. Centrifugal Casing
8. Continuous Pultrusion
9. Continuous Laminating
10. Continuous Laminating
11.  Braiding
12. Matched-Die Molding

1. Hand Lay Up

Hand lay up is the oldest but still widely used fabrication technique employed in the 

reinforced plastics industry. A large variety of products can be fabricated with this

method, reaching from smallest parts to large coverings or even sports boats. A negative

and/or positive mould, a semi-finished fibre product (desired fibre fabric) and a thermoset 

resin (unsaturated polyester or epoxy resin)are required for the process. Both materials 

are alternately laid up in the mould and consolidated with a roller. After that, the moulding 

is allowed to cure either at room temperature or warm in a curing oven.

1. Apply Gel-Coat with brush or soft roller.

2. Apply laminating resin with brush.

3. Cut the fit reinforcement layer.

4. Consolidate with ribbed roller. Repeat 2. 3. 4. until required build-up achieved. 

Contact Molding

2. Vacuum Bag Molding

Carbon Headlight. Koenigsegg.

Carbon Headlight manufacturing
The first layer must settle on the mold.

The mold is prepare for baking.



Suck air out of the plastic bag.




3. Pressure Bag

4. Autoclave

This may be the most important method to manufacture the composite. I write another article
to introduce it.

5. Spray Up

6. Filament Winding

7. Centrifugal Casing

8. Continuous Pultrusion

9. Continuous Laminating

3.3 MMC Fabrication Methods

3.4 CMC Fabrication Methods