The working principle of the direct reading spectrometer

With the gradual increase in steel production, people have higher requirements for the accuracy of product analysis and testing results. When testing steel products, it is necessary to use direct reading spectrometers for testing. However, in the specific testing process, Due to the influence of the excitation light source and the composition of the test object, the test results often show a certain degree of error. Based on this, combined with the working principle of the direct-reading spectrometer, taking stainless steel products in steel materials as an example, the causes of errors in the detection of stainless steel components and the elimination countermeasures are analyzed in depth.

1. The working principle of the direct reading spectrometer

The direct-reading spectrometer is an emission spectrometer, which mainly measures the intensity of the characteristic spectral light that represents each element when the sample is excited to quantitatively analyze the sample. Divided into 4 modules according to function:

1. Excitation system: The task is to fully atomize the solid sample through various methods and emit the emission spectrum light of each element

2. Optical system: process the complex optical signals generated by the excitation system (sort, separate, filter, capture)

3. Measurement and control system: Measure the intensity of the characteristic spectral line representing each element, and through various means, convert the light intensity signal of the spectral line into a digital electrical signal that can be recognized by the computer, and control the normal operation of the entire instrument

4. The software data processing system in the computer: Perform various algorithm calculations on the light intensity data of each channel received by the computer to obtain a stable and accurate sample content.

2. Causes of errors when the direct-reading spectrometer detects the composition of stainless steel

In the process of using a direct reading spectrometer to detect the composition of stainless steel, there is such a problem that the same measurement personnel uses the same measurement method and measuring instrument to perform multiple tests on the same sample, and the test results cannot be guaranteed. The same. In this case, it can be seen that the detection error is inevitable, and there are many reasons for the error. The main reasons are as follows:

1. The instability of the excitation light source. There is no obvious boundary between the evaporation or excitation of stainless steel during detection. These processes are almost synchronized. In this case, it will affect the detection results to a certain extent.

2. The test object affects the test results. In the process of testing, one test condition cannot be used to analyze the components in stainless steel. For example, the analysis of the working conditions of steel is not suitable for the analysis of non-ferrous metals.

3. The purity of argon will cause errors in the test results.

4. The content of alloying elements in stainless steel is relatively high, so the analysis of the content of non-metallic elements is inaccurate.

5. The electrode of the operating table is contaminated, resulting in a high content of alloying elements in it, which leads to unreasonable test results.

3. Countermeasures for error elimination when detecting stainless steel components by the direct reading spectrometer

Given the causes of the above detection errors, in the specific detection process, it is necessary to control each link. Generally, the error elimination countermeasures include the following aspects:

1. Sampling correctly. When performing spectral analysis, the sampling method and the processing results of the sample will also have a certain impact on the accuracy of the detection. For stainless steel with high carbon content, it is necessary to use warm and cold after cutting it. Can avoid sample cracks.

2. Improve the detection level of operators. In the detection process, it is necessary to ensure that the operator is proficient in the operation of the instrument and has a sufficiently deep understanding of the samples and analysis methods.

3. Testing equipment. To improve the accuracy of the detection and analysis results and eliminate the errors, the equipment used in it needs to be maintained accordingly to ensure the overall accuracy of the spectrometer and meet the required standards for detection. In addition, it is also necessary to strictly control the performance of the light source. control.

4. Samples and testing environment. Before sample testing, it is necessary to strictly control the temperature, humidity, lighting, electromagnetic interference, and other conditions of the sample testing environment to ensure the overall stability of the instrument.

Summary: When using a direct-reading spectrometer to detect stainless steel components, due to the influence of samples, operators, testing instruments, and testing methods, there will be a certain degree of error in the testing results, which requires operators to have rich operations Experience, and ensure that the equipment and samples are in the standard testing state, to ensure the overall accuracy of the testing.