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Figure 10: Schematic diagram of the float process for making flat glass. A glass ribbon, soft enough to be workable, is fed from a glass-melting furnace and passed between rollers into the float bath. There, it floats on molten tin under a controlled atmosphere of nitrogen and hydrogen (N2/H2) that prevents oxidation of the tin. As the bulk of that glass begins to cool, the surface is heated and polished in order to remove surface blemishes and then allowed to cool also. The ribbon exits the float bath and passes through the annealing lehr, where it is cooled uniformly in order to prevent the formation of nonuniform internal stresses that may warp the glass. The cooled glass is then scored by diamond-tipped cutters, and individual sheets are separated and stacked.
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Figure 10: Schematic diagram of the float process for making flat glass. A glass ribbon, soft enough to be workable, is fed from a glass-melting furnace and passed between rollers into the float bath. There, it floats on molten tin under a controlled atmosphere of nitrogen and hydrogen (N2/H2) that prevents oxidation of the tin. As the bulk of that glass begins to cool, the surface is heated and polished in order to remove surface blemishes and then allowed to cool also. The ribbon exits the float bath and passes through the annealing lehr, where it is cooled uniformly in order to prevent the formation of nonuniform internal stresses that may warp the glass. The cooled glass is then scored by diamond-tipped cutters, and individual sheets are separated and stacked.
Figure 10: Schematic diagram of the float process for making flat glass. A glass ribbon, soft enough to be workable, is fed from a glass-melting furnace and passed between rollers into the float bath. There, it floats on molten tin under a controlled atmosphere of nitrogen and hydrogen (N2/H2) that prevents oxidation of the tin. As the bulk of that glass begins to cool, the surface is heated and polished in order to remove surface blemishes and then allowed to cool also. The ribbon exits the float bath and passes through the annealing lehr, where it is cooled uniformly in order to prevent the formation of nonuniform internal stresses that may warp the glass. The cooled glass is then scored by diamond-tipped cutters, and individual sheets are separated and stacked.

Flat glass refers to sheets of glass that are drawn or rolled, used primarily for windows and mirrors. The Romans were among the first to develop flat glass for windows, with early methods like casting and the medieval crown process producing uneven disks. The broad glass process, which involved blowing large cylinders that were then flattened, allowed for larger pieces but still had surface waviness.123

Modern production relies heavily on the float process, where molten glass is floated on a bath of molten tin. This method yields glass with excellent thickness control and strength, eliminating the need for grinding and polishing. Glass is an elastic solid, resistant to corrosion, and its properties are largely isotropic, meaning they are the same in all directions. While glass can exhibit plastic deformation under a diamond microindenter, it typically fails in a brittle manner due to its amorphous atomic structure.24

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  3. industrial glass - Elasticity and plasticity
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