Main raw material: high purity quartz sand
Main outcome measures: (unit: ppm)
1. Excipients:
① The graphite electrode is made of 76mm thick high purity electrode rod
Ash content: < 80ppm
False specific gravity: 1.6g/cm
Specific resistance: < 15 × 10 Ω. Cm
Bending strength: > 1.47 × 10Pa
② Graphite mould
Ash content: < 200ppm
False specific gravity: 16g / cm
Bending strength: > 1.67 × 10Pa
③ Large size quartz heat shield
Purity: Al < 200 Na < 30 Li < 30
Fe<30 K<30
The main chemical composition of quartz crucible is silica, which does not react with other acids except hydrofluoric acid, but easily reacts with caustic alkali and alkali metal carbonate
The quartz crucible has good thermal stability and can be heated directly on the flame
Quartz crucibles, like glassware, are easy to break, so you should be careful when using them
Potassium bisulfate (sodium) and sodium thiosulfate (dried at 212 ℃) can be used as fluxes in quartz crucible. The melting temperature shall not exceed 800 ℃.
