Functions of Boron Oxide in Glass Manufacturing

Boron Oxide plays multiple roles in glass manufacturing, primarily including lowering the melting temperature, promoting fusion, enhancing glass stability, improving physical properties, and adjusting optical performance.  

Firstly, boron oxide significantly reduces the melting temperature of glass.At high temperatures, boron oxide exhibits high reactivity, enabling it to react with other oxides to form low-melting-point eutectic mixtures, thereby lowering the glass melting temperature. This not only contributes to energy savings but also accelerates the glass fusion process.  

Secondly, boron oxide improves the thermal and chemical stability of glass.It reduces the thermal expansion coefficient of glass, thereby enhancing its thermal stability and minimizing deformation or cracking under heat. Additionally, boron oxide strengthens the glass's resistance to chemical substances such as acids and alkalis.  

Boron oxide enhances the physical properties of glass. In glass, boron oxide exists in the form of [BO₄] tetrahedra and [BO₃] triangles. The [BO₄] tetrahedra participate in the glass network formation, reinforcing structural strength and mechanical properties, while the [BO₃] triangles provide free oxygen, facilitating melting temperature reduction and promoting the fusion and homogenization of other oxides.  

Finally, boron oxide can also adjust the optical properties of glass. It increases the refractive index of glass, thereby improving light transmittance and optical performance, which is crucial for manufacturing optical glass, fiber optics, and other optical devices.  

However, it should be noted that excessive boron oxide may increase the thermal expansion coefficient of glass, thereby reducing its thermal stability.Additionally, boron oxide raw materials are prone to volatilization, which may complicate the homogenization process during glass melting. Therefore, the addition of boron oxide must be strictly controlled in glass production.