glassclad

Glassclad is a general term in materials science describing a composite material in which a surface layer of glass is bonded to a substrate, typically metal, ceramic, or plastic. The glass coating provides properties such as chemical resistance, wear resistance, electrical insulation, or a decorative finish, while the substrate supplies mechanical strength, thermal stability, or structural form. The term is used in various industries and contexts, and there is no single standardized specification for it.

In optics, the phrase glass-clad is common in glass-clad optical fibers, where a core of glass is surrounded by a cladding layer of glass with a lower refractive index. This arrangement enables total internal reflection and light guidance within the core.

Techniques for applying glass cladding include fusing or enameling (glazing) onto metal surfaces, frit deposition followed by firing, and various deposition or spraying methods to form a continuous glass layer. Glass cladding can also be achieved by bonding a glass layer to the substrate through thermal or chemical processes, followed by controlled cooling to manage stresses.

Applications include enamelware and coated cookware (glass-coated steel or iron), corrosion- or heat-insulating coatings on metal components, electrical insulators with a glass layer, and optical fiber cables that use a glass cladding to confine light.

Performance depends on adhesion between glass and substrate, thermal expansion compatibility, and resistance to cracking or delamination. Glassclad systems offer protective and functional surface properties but may introduce brittleness and processing complexity.