Cladding is used to allow light signals to be transmitted through fiber optic lines. A simple optical fiber consists of a core and cladding. The core has a higher refractive index than the cladding. When light passes through the core and reaches the cladding, it is refracted back into the core. Cladding is used instead of a reflective coating around the core because refraction of light absorbs virtually no light energy, while reflection absorbs 50 percent or more energy. Light signals would die out after only a few meters in fiber optics with reflective coatings, while fiber optics with cladding can transmit light signals for thousands of miles.
Metals are clad through a process of high temperature and pressure. Two sheets of different metal are placed together, heated and compressed together using a high-pressure press or calendar rolls. The process fuses the two metals, leaving one surface on each side of each metal. This process was used to make the first silverplate objects, using a sheet of copper for the inside of objects, leaving the more expensive silver side on the outside.
Construction materials such as pipes or building siding can be clad for protection from the elements or for aesthetic reasons. Pipes are clad to provide corrosion resistance and insulation. Siding can be clad to render it waterproof or air tight. Cladding can also be used to add a decorative touch to siding.
Nuclear reactor fuel is placed in a coolant bath to control the nuclear reaction speed. The bare fuel rods are clad with another metal to prevent the nuclear fuel from breaking down and contaminating the coolant bath.
Cladding is the process where any material is laid in close contact with another material. It refers, for almost any number of reasons, to the permanent or semi-permanent attachment of a surface material to a base material.