What Are the Differences of JGS1 and JGS2 Quartz Glass?

   In the field of optical quartz glass, JGS1 and JGS2 are two mainstream national standard grades of quartz glass in China (in line with GB/T 7895-2008). Both are high-performance fused quartz materials with excellent optical, thermal and mechanical properties, but there are obvious differences in raw material selection, manufacturing process, core performance and application scenarios due to different positioning. This paper will detail the intrinsic differences and typical application fields of JGS1 and JGS2 to provide a clear reference for material selection in industrial production and scientific research.

1. Core Composition & Manufacturing Process: The Fundamental Difference

The essential difference between JGS1 and JGS2 lies in raw material purity and melting process, which directly determines their subsequent performance differences:

JGS1 (Infrared Optical Quartz Glass)

Raw material: High-purity synthetic quartz powder (artificially synthesized SiO₂, almost free of natural impurities)

Melting process: Vacuum induction melting or hydrogen-oxygen flame melting under high-purity protective atmosphere, with strict control of hydroxyl (OH) content and metal impurities

Purity index: SiO₂ content ≥99.995%, total metal impurities ≤5 ppm, hydroxyl content ≤50 ppm (even lower in high-end grades)

JGS2 (Ultraviolet Optical Quartz Glass)

Raw material: High-quality natural crystal or purified natural quartz sand (natural SiO₂ ore after physical and chemical purification)

Melting process: Hydrogen-oxygen flame melting under atmospheric pressure, the purification process is simpler than JGS1

Purity index: SiO₂ content ≥99.9%, total metal impurities 20~80 ppm, hydroxyl content 100~200 ppm

In short, JGS1 is a synthetic high-purity quartz glass with man-made raw materials and strict melting control; JGS2 is a natural fused quartz glass with purified natural raw materials and a more economical manufacturing process.

2. Key Performance Differences: Optical, Thermal and Purity

Based on the differences in composition and process, JGS1 and JGS2 show obvious differentiation in optical transmission, impurity content, thermal stability and other core performances.