Which method involves heating plastics and forming them over a mould?

The method that involves heating plastics and forming them over a mould is heat forming. This technique is commonly used for thermoplastics, which can be softened upon heating and then shaped into desired forms. The process typically involves heating the plastic sheet until it becomes pliable, after which it is placed over a mould. A vacuum or mechanical pressure is then applied to ensure the plastic takes on the shape of the mould as it cools and solidifies. This approach is particularly effective for creating complex shapes and large components in a variety of designs.

Lamination involves layering materials together, typically for strength or aesthetic purposes, and does not specifically refer to the heating and forming process over a mould. Transfer moulding and injection moulding, while also processes related to shaping plastics, involve injecting heated material into a mould rather than manually forming it over one. Thus, heat forming is distinctly focused on the technique of creating shapes by applying heat and using a mould.