What term describes materials made by uniting superimposed layers of different substances?

The term that describes materials made by uniting superimposed layers of different substances is "laminates." Laminates are specifically designed by layering various materials together, which allows for the combination of properties from each layer. This technique can enhance the strength, durability, or aesthetic qualities of the final product.

For instance, laminate materials are widely used in construction and manufacturing to create surfaces that are both visually appealing and capable of withstanding wear and tear. The process involves bonding layers together, which not only results in a composite effect but also helps in improving functionality, such as water resistance or heat insulation.

While composites refer to materials made by combining different substances to create new properties, they do not necessarily imply the layered structure that laminates do. Assemblies refer more broadly to collections of items put together, without necessarily emphasizing their layered nature. Mixtures, on the other hand, generally describe combinations of materials that are blended but do not imply any specific structural arrangement like layering. Hence, laminates precisely capture the concept of superimposing layers of different substances.