The following is an analysis of the key influencing factors on the measurement results of high-frequency infrared carbon sulfur analyzer:

1、 Sample preparation and weighing process

1. Particle size uniformity: The sample needs to be ground to a uniform fine powder (usually ≤ 0.1mm). Large particles can easily lead to incomplete combustion, resulting in delayed carbon/sulfur release or low total amount.

2. Weighing accuracy: The balance accuracy should reach the level of 0.1mg, and slight deviations (especially for low content samples) will significantly amplify relative errors.

3. Surface adsorption interference: Metal powders are prone to adsorbing water vapor, oil, or organic matter in the air, and need to be removed through pre-treatment in a drying oven (such as baking at 105 ℃).

4. Blank correction: If the crucible and flux contain carbon/sulfur impurities, a blank test should be conducted in advance and the background value should be deducted.

2、 Selection and proportion of flux

1. Oxidation ability matching: The combination of tungsten particles, tin particles, pure iron and other fluxing agents needs to be adjusted according to the characteristics of the sample. For example, refractory metal ores require the addition of highly oxidizing vanadate fluxes.

2. Coverage effect: The flux should wrap around the sample particles to prevent splashing loss; Excessive addition may dilute the target signal.

3. Blank contribution: Some fluxes (such as tin particles) contain trace amounts of sulfur and require the use of ultra-low carbon/sulfur certified products.

3、 Stability of infrared detection unit

1. Attenuation of light source intensity: After long-term use, the energy of the infrared lamp decreases, and the working curve needs to be calibrated regularly.

2. Air chamber pollution: by-products such as water vapor and SO3 deposit on the surface of the gold mirror, forming a mirror blurring effect.

3. Electronic drift: Insufficient preheating during startup (<30 minutes) leads to unstable circuit reference and abnormal initial test data.

4、 Environmental and human factors

1. Temperature and humidity fluctuations: When the environmental humidity exceeds 60% RH, the sample absorbs moisture and introduces additional moisture interference; Sudden temperature changes cause airflow disturbances.

2. Cross contamination: High content samples remain in the pipeline, and subsequent low content tests exhibit a "memory effect".

3. Operational standardization: Incorrect sample addition sequence (such as adding flux first and then adding sample), missing ceramic gaskets, etc. can all lead to data distortion.

5、 Reliability of calibration system

1. Traceability of reference materials: National recognized standard steels (such as GBW series) must be used to avoid introducing systematic errors into self-made standard samples.

2. Dynamic range adaptation: The calibration curve should cover the concentration range of the sample, and high content samples that exceed the linear range should be diluted and retested.

3. Multi point calibration frequency: At least high and low point calibration should be performed daily, and full range calibration should be performed weekly.

The results of high-frequency infrared carbon and sulfur analysis are influenced by the synergistic effect of multiple links, among which the combustion system parameters (furnace temperature, oxygen flow, catalytic efficiency) and the status of the infrared detection unit are the most critical. Establishing standardized operating procedures (SOP), regularly maintaining equipment, and strictly using certified standards are the core measures to ensure data accuracy. For complex matrix samples, it is recommended to use weighted regression correction algorithm to eliminate matrix effects.