YS/T 896-2024 in English

Technical Background of the Standard

This standard is formulated to meet the quality control requirements of 25 key trace impurities in high-purity niobium materials (purity ≥99.99%), with a detection limit of 0.0001%. With the development of semiconductor and superconducting material industries, the requirements for impurity control of high-purity metals are becoming increasingly stringent, and traditional spectroscopy can no longer meet the requirements.

Detailed explanation of the method principle

Using the inductively coupled plasma mass spectrometer (ICP-MS) mass resolution mode (0.8u) combined with internal standard correction method:

Key operating specifications

1. Reagent system

Use high-grade pure reagents, pay special attention to:

• Hydrofluoric acid (ρ=1.16g/mL) needs to be stored in PTFE container
• Rhodium internal standard solution (1μg/mL) needs to be prepared on the same day

2. Instrument configuration requirements

ICP-MS must be equipped with:

• Hydrofluoric acid resistant nebulization system (such as PFA material)
• Dynamic reaction cell (to eliminate Ar⁺H⁺ interference)
• Mass calibration components (need to be calibrated with tuning solution every day)

Analysis of implementation points

1. Isotope selection

Standard recommended monitoring isotopes to avoid mass interference:

2. Tolerance control

Set relative tolerance according to content segmentation:

• 0.0001-0.0003%: ≤120%
• ＞0.005-0.010%: ≤20%

Application Cases

Example:When a superconducting material factory used this standard to detect high-purity niobium ingots:

1. Abnormal Ti content was found (0.0021%)
2. Traced back to contamination of the raw material hydrogen purification system
3. After improvement, the Ti content dropped to 0.0004%

Technical Development Suggestions

• Added detection of semiconductor sensitive elements such as Ge and Se
• Developed microwave digestion pretreatment methods
• Promoted localization of reference materials