**4.5 Filament winding**

employed by The Boeing Co. (Chicago, IL, USA) and NASA, as well as small fabricating firms, to produce aerospace-quality laminates without an autoclave [36, 44]. **Figure 6** presents the schematic of the resin film infusion process.

*Composite and Nanocomposite Materials - From Knowledge to Industrial Applications*

Compression moulding is a precise and potentially rapid process for producing high-quality composite parts in a wide range of volumes. The material is manually or robotically placed in the mould. The mould halves are closed, and pressure is applied using hydraulic presses. Cycle time ranges depending on the part size and thickness. This process produces high-strength, complex parts in a wide variety of sizes. The composites are commonly processed by compression moulding and include thermosetting prepregs, fibre-reinforced thermoplastic, moulding compounds such as sheet moulding compound (SMC), bulk moulding compounds (BMC), and chopped thermoplastic tapes. **Figure 7** shows the schematic of the compression moulding process.

Injection moulding is a closed process as shown in **Figure 8**. This is fast, highvolume, low-pressure, and most commonly used for filled thermoplastics, such as nylon with chopped glass fibre. The injection-moulding process has been in use for

**4.3 Compression moulding**

*The schematic of the resin film infusion process.*

**Figure 5.**

**Figure 6.**

*The schematic of the VARTM process.*

**4.4 Injection moulding**

**16**

Filament winding is a continuous fabrication method that can be highly automated and repeatable, with relatively low material costs as shown in **Figure 9**. A long, cylindrical tool called a mandrel is suspended horizontally between end supports. Dry fibres are run through a bath of resin to be wetted. The fibre application instrument moves back and forth along the length of a rotating mandrel with the traverse carriage, placing fibre onto the tool in a predetermined configuration. Computer-controlled filament-winding machines are used to arrange the axes of motion [46–48]. Filament winding is one example of aerospace composite materials.
