I. Introduction to Glass

Soda-lime-silica glass is the most widely produced and commonly used ordinary silicate glass. Typical products include flat glass, food and beverage bottles, and daily-use ware. Its basic framework consists of silicon dioxide (SiO₂). Sodium oxide (Na₂O) is added as a flux to lower the melting temperature, while calcium oxide (CaO) is incorporated to improve chemical stability and mechanical strength. It also contains small amounts of magnesium oxide, aluminum oxide, potassium oxide, as well as trace impurities such as iron and titanium.

The typical composition ranges are: SiO₂ 70%–75%, Na₂O 12%–15%, CaO 10%–12%, supplemented by minor MgO and Al₂O₃. Benefiting from easily available raw materials, excellent formability and favorable light transmittance, soda-lime-silica glass is widely used in construction, packaging, consumer goods and other fields.

II. Application of ScopeX in Glass Testing

The properties of soda-lime-silica glass are highly dependent on its chemical composition ratio. Even minor fluctuations in composition can directly alter the glass's thermal expansion coefficient, water resistance, mechanical strength, light transmittance, and crystallization tendency. In glass production quality control, it is necessary to rapidly monitor both major and minor components to ensure batch-to-batch consistency of finished products. Traditional wet chemical analysis offers high accuracy, but involves complex sample preparation, lengthy digestion times, and large quantities of chemical reagents, resulting in long testing cycles that cannot meet the rapid quality control needs of production lines.

X-ray fluorescence spectrometry (XRF) enables non-destructive, simultaneous multi-element detection and has become the mainstream method for incoming raw material inspection, production process monitoring, and finished product sampling of soda-lime-silica glass. Conventional XRF suffers from severe absorption of characteristic X-rays from light elements such as sodium and magnesium, resulting in significant testing errors and an inability to stably quantify alkali metal components in soda-lime-silica glass. Therefore, vacuum-type XRF has become the preferred solution.

The ScopeX vacuum-type X-ray fluorescence spectrometer is equipped with an intelligent vacuum sample chamber that eliminates air absorption of characteristic fluorescence from light elements, significantly improving the excitation efficiency and detection sensitivity for light elements such as Na, Mg, Al, and Si. It is ideally suited for simultaneous quantitative analysis of major and minor elements in soda-lime-silica glass systems.

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III. Testing Case

(1) Case Introduction: A soda-lime-silica glass sample from a manufacturer was tested using the ScopeX vacuum-type X-ray fluorescence spectrometer to verify whether its composition met the requirements.

(2) Sample Preparation: A corresponding proportion of mixed flux and soda-lime-silica glass powder was weighed and mixed thoroughly, then melted to form a glass bead. The bead was removed and cooled for later use.

(3) Test Results:

(4) Conclusion: The test results show that SiO₂, Na₂O, and CaO are the major components, MgO and Al₂O₃ are the minor components, and Fe₂O₃ is a trace impurity. The relative standard deviation (RSD) of the major components is satisfactory, and the repeatability for light elements Na and Mg is good. The deviations between the measured values and the reference values are within the allowable error range specified by the national standard.

V. Conclusion

The ScopeX vacuum-type X-ray fluorescence spectrometer addresses the shortcomings of conventional XRF instruments in light element detection through its vacuum system, enabling rapid and non-destructive simultaneous quantification of major and minor components in soda-lime-silica glass. The testing repeatability is good, and the analytical results meet the national standard requirements for production quality control of soda-lime-silica glass. It can effectively monitor fluctuations in the composition of raw materials and finished products and facilitate timely adjustments to furnace batching processes. It has good application value in the quality control of flat glass, packaging glass bottles, and daily-use soda-lime-silica glass.