Heat treatment method of quartz glass

[0035] Put the silica powder in a sintering furnace at 1600°C for vitrification treatment. After the powder is completely vitrified, cool down to 1300°C at a rate of -300°C / h, and then cool down at a rate of -50°C / h To the heat treatment temperature of 1200°C, keep it for 2 hours, then lower the temperature to the first annealing point temperature of 950°C at the first annealing rate of -15°C / h, and finally lower the temperature to room temperature at the second annealing rate of -100°C / h, the obtained transparent quartz glass The stress birefringence reaches 1.7nm / cm, and the data results are shown in Table 1.

[0037] Place the silica powder in a sintering furnace at 1600°C for vitrification treatment. After the powder is completely vitrified, cool down to 1300°C at a rate of -300°C / h, and then cool down at a rate of -100°C / h To the heat treatment temperature of 1150°C, keep it for 3 hours, then lower the temperature to the first annealing point temperature of 930°C at the first annealing rate -3°C / h, and finally lower the temperature to room temperature at the second annealing rate -100°C / h, the obtained transparent quartz glass The stress birefringence reaches 0.5nm / cm, and the data results are shown in Table 1.

[0039] Place the silica powder in a sintering furnace at 1600°C for vitrification treatment. After the powder is completely vitrified, cool down to 1300°C at a rate of -400°C / h, and then cool down at a rate of -150°C / h To the heat treatment temperature of 1100°C, keep it warm for 5 hours, then lower the temperature to the first annealing point temperature of 900°C at the first annealing rate -8°C / h, and finally lower the temperature to room temperature at the second annealing rate -150°C / h, the obtained transparent quartz glass The stress birefringence reaches 1.3nm / cm, and the data results are shown in Table 1.