Float glass

Float glass is soda lime glass produced as flat sheet, which can be further processed by bending, strengthening and laminating. It is named after the method of production: molten glass is floated on a pool of liquid tin to produce a perfectly flat and smooth sheet.

Its technical strength is far higher than its practical strength. Glass is very brittle and any imperfections (scratches or flaws, for example) act as a stress concentrator, causing premature failure when even a relatively small amount of tension is applied, such as by bending. So even though the theoretical strength is in the order of GPa, tiny imperfections reduce the strength down to around 14 MPa. The mechanical properties are enhanced with strengthening and tempering, which can raise tensile strength to 40 and 70 MPa, respectively.