What is the difference between borosilicate and fused quartz?

Differences Between Borosilicate and Fused Quartz

Borosilicate and Fused Quartz are two types of glass materials used extensively in the optical and scientific industries due to their unique properties. However, they differ significantly in composition, thermal properties, and applications.

Composition

• Borosilicate: Composed mainly of silica and boron trioxide, this glass is known for its low coefficient of thermal expansion.
• Fused Quartz: Made almost entirely of silica (SiO2), offering exceptional purity and thermal shock resistance.

Thermal Properties

• Borosilicate: Exhibits a low coefficient of thermal expansion, making it resistant to thermal shock and suitable for applications involving sudden temperature changes.
• Fused Quartz: Has an even lower coefficient of thermal expansion than borosilicate and can withstand very high temperatures, up to 1200°C, without deforming.

Optical Properties

• Borosilicate: Provides good optical clarity but can have slight coloration depending on its composition.
• Fused Quartz: Offers superior optical clarity and is virtually free from coloration, making it ideal for high-precision optical applications.

Applications

• Borosilicate: Widely used in laboratory glassware, telescopes, and lighting due to its durability and resistance to chemical corrosion.
• Fused Quartz: Preferred in semiconductor manufacturing, fiber optics, and precision optics where high temperature resistance and optical purity are critical.

Cost

Due to its higher purity and more complex manufacturing process, fused quartz is generally more expensive than borosilicate.