GB/T 4121-2014Test method for stability to thermal darkening of quartz glass (English PDF)

3.1 high-temperature furnace

temperature not lower than 1300 °C, furnace temperature accuracy of 1 °C, temperature fluctuation is less than or equal to 5 °C.

3.2 Electric oven

temperature not lower than 110 °C.

3.3 Spectrophotometer

wavelength range comprising 200nm ~ 380nm, the transmittance measurement accuracy is not less than 0.1%.

3.4 Sample case

made of transparent quartz glass, with cover.

3.5 vernier caliper

accuracy no less than 0.02mm.

3.6 ethanol

AR.

3.7 Deionized water

Conductivity (25 °C) not more than 0.50mS/m.

3.8

chrome crucible tongs and clamps Teflon.

3.9

glass beaker.

4.1

3 samples of the same batch transparent.

4.2

The shape and size should be in accordance with Table 1.

Table 1

Sample Type Sample shapes and sizes

6mm ~ 40mm diameter quartz glass tube

Cut height of 30mm ~ 40mm of pipe sections, and cut in half in the axial direction, take half of them sample

More than 40mm diameter quartz glass tube is cut height of 30mm ~ 40mm pipe, 25mm chord length of the sample

Other products

Cut 35mm × 25mm × s sample, s an article of the original thickness; thickness greater than 5mm when the article

When a thickness of about 5mm cut the sample, the test surface shall be mechanically polished 4.3 Sample test surface shall not be colored thread, crystal pattern, obviously grooves and ridges or a width greater than 1mm gas lines, air bubbles, scratches, etc. affect the transmission ratio detection

Defects. Mechanical polishing test surface should be smooth and transparent, no pitting, no scratches.