Reactivity of Fused Quartz

Reactivity of Fused Quartz

For general use, fused quartz is unreactive, including when exposed to most acids, metals, chlorine and bromine at ordinary temperatures. It is slightly attacked by alkaline solutions, the reaction rate increasing with temperature and concentration of solution. Phosphoric acid will attack fused quartz at temperatures about 150 °C. Hydrofluoric acid alone will attack at all temperatures. Carbon and some metals will reduce fused quartz; basic oxides, carbonates, sulfates, etc., will react with it at elevated temperatures.

Rate of Dissolution

Pressure Determination of Fused Quartz

For applications where fused quartz tubing is exposed to internal pressures, the following formula helps determine the maximum pressure which can be applied at room temperature.

CFQ Rupture Formula For Tubing

S = pr/t 
Where:
S = Hoop Stress (Pa)
p = Working pressure (Pa)
r = Inside Radius of Tube (mm)
= Wall Thickness (mm)

This formula is not applicable when the internal pressure exceeds 7×105 Pa (100 psi).