Which nozzle material is clear?

Which nozzle material is clear?

• A. Fused quartz
• B. Silicon nitride
• C. Alumina
• D. Ceramic

Answer: (A)

In GTAW, having a transparent viewing window on the nozzle lets you watch the arc and the weld pool without removing the nozzle. Fused quartz is clear to visible light, so it provides that viewing capability while still standing up to the heat of welding. The other common nozzle materials—silicon nitride, alumina, and other ceramics—are opaque, so they don’t permit seeing through them. Fused quartz combines the needed visibility with adequate thermal performance for many tasks, though it can be sensitive to thermal shock if treated roughly.

In GTAW, having a transparent viewing window on the nozzle lets you watch the arc and the weld pool without removing the nozzle. Fused quartz is clear to visible light, so it provides that viewing capability while still standing up to the heat of welding. The other common nozzle materials—silicon nitride, alumina, and other ceramics—are opaque, so they don’t permit seeing through them. Fused quartz combines the needed visibility with adequate thermal performance for many tasks, though it can be sensitive to thermal shock if treated roughly.