Which method is specifically used for shaping thermoplastics?

Injection moulding is the correct method for shaping thermoplastics due to its efficiency and effectiveness in producing complex shapes with high precision. This process involves melting thermoplastic material and injecting it into a mould where it cools and solidifies into the desired form.

Thermoplastics, by their nature, can be reheated and reshaped without undergoing chemical change, making injection moulding particularly suitable for mass production of components since the same mould can be used repeatedly to create identical parts. The ability to finely control the temperature and pressure during the injection process helps achieve high-quality finishes and intricate designs.

Other methods mentioned, such as foaming, lamination, and welding, either do not specifically shape thermoplastics or are not as effective for this type of material. Foaming typically relates to creating a material with a cellular structure rather than shaping it. Lamination involves layering materials and is more associated with reinforcement than shaping. Welding refers to joining materials together rather than forming new shapes.