Some standard content:
Guiding Technical Documents of the Ministry of Electronics Industry of the People's Republic of China General Rules for Emission Spectrum Analysis Methods for Vacuum Materials SJ/Z3206.12-89
This standard applies to the general rules for emission spectrum analysis methods for materials such as metals and their alloys, glass and ceramics used in vacuum devices.
1 Characteristics of vacuum materials and requirements for analysis methods 1.1 The same type of materials has a wide variety of specifications, complex shapes, and a small number of samples, so a unified analysis method is required.
1.2 The purity of the material is high and a purity test method that can be used to determine multiple trace elements is required. 1.3 The intermediate products of the material sometimes also require analysis, so an analysis method with the least sample is required. Instruments and Equipment
The following instruments and equipment can be selected according to the needs of the analysis. 2.1 Spectrum excitation source See SJ/Z3206.2~89 (Excitation source for emission spectrum analysis and its performance requirements). 2.1.1 DC arc generator, used to excite powdered samples. 2.1.2 AC arc generator, used to excite rods, bulk metal and alloy samples, and residues of solution samples. 2.1.3 High-voltage spark generator, used in conjunction with AC arc generator. 2.1.4 Inductively coupled high-frequency argon plasma generator, used to excite solution test samples. 2.1.5 Laser excitation source, used to excite micro-area samples. 2.2 Spectrometer, see SJ/Z2303.3-39 (Instruments for emission spectrum analysis and their performance requirements). 2.2.1 Spectrograph with medium dispersion, used to record spectra of materials with less complex spectral lines. 2.2.2 Spectrograph with large dispersion, used to record spectra of materials with more complex spectral lines. 2.2.3 Photometer, used to directly record spectra and calculate the content of the measured components. 2.2.4 Spectroscope, used to visually identify the grades and classifications of metals and alloys. 2.3 Microphotometer, see SJ/Z2306.3-89. Used to measure the intensity of the spectrum sheet on the spectrum sheet, and conduct retrograde quantitative analysis.
2.4 Spectrometer, observe and compare the spectrum lines on the spectrum line, and conduct qualitative and semi-quantitative analysis. 2.5 Sample preparation equipment, grinding mixer, sample press and mold. 2.6 Chemical treatment instruments, muffle furnace, oven, balance, etc. 3: Qualitative and semi-quantitative analysis
3.1 Qualitative analysis.
3.1.1 The qualitative and quantitative analysis methods of general materials shall be carried out in accordance with the provisions of SJ/Z2306.10--89 (Emission Spectrum Qualitative Analysis Method Approved by the Seventh Ministry of Electronics Industry of the People's Republic of China on February 10, 1989 and Implemented on March 1, 1989
SJ/Z8206.12-89
General Rules) and SJ/22306.11-89 (Emission Spectrum Quantitative Analysis Method General Rules). 3.1.2 The only tiny sample should be carefully placed in a small-hole graphite electrode that has been burned in the air with a large current. If necessary, a small amount of graphite powder can be covered and compacted to prevent sample loss. At the anode of the DC arc, the arc is ignited by electrode contact, the sample is completely burned and the spectrum is recorded. It is compared with the blank test spectrum taken under the same conditions to make a judgment on the sample composition. 3.1.3 The evaporated material on the inner wall or parts of the device is dissolved with an appropriate acid or transferred to the small-hole graphite plate or flat-head electrode by other methods. After drying, it is excited in the DC arc for spectrum photography. The cathode layer enrichment phenomenon can be used to reduce the detection limit of the determination, and the laser can also be used to directly excite the sample. During the analysis, a corresponding blank test must be performed to make component identification. 3.1.4 For gas samples in gas-filled devices or sealed tubes, the gas is excited to emit light using an appropriate method, and the spectrum is recorded to make a composition estimate.
3.2 Semi-quantitative analysis.
3.2.1 Spectrophotometry Semi-quantitative analysis can be performed using the mean line pair method, number order method, comparative spectrum method, line development method, etc.
3.2.2 Spectrum semi-quantitative analysis can be performed using the general metal and alloy spectrum method, or using the spectrum analysis method developed by the specific material.
4 Quantitative analysis
4.1 Solid method For ferrous and non-ferrous metals and alloys used in the vacuum industry, if the samples can be made into rods or block electrodes that are compatible with commercially available standard samples, solid methods should be used as much as possible for analysis. Generally, AC arc and high-voltage sparks are used. High-frequency sparks can also be used to excite the samples, which has higher accuracy. 4.2 Powder method According to the characteristics of vacuum materials, the DC arc powder method can meet the analysis requirements of most vacuum materials.
Except for silicate and ceramic samples in powder state, metal materials of various shapes and specifications are dissolved with appropriate acids, burned at appropriate temperatures to form stable oxides, or dried to form stable salts. The sample is uniformly present in a form, excited by a DC arc or an AC arc, and a laboratory-synthesized powder standard sample is used. In order to reduce the detection limit of impurity determination, a controlled atmosphere and an external magnetic field can be used. The detection limit is generally 10\4~10~5%, and the relative standard deviation of the analysis is 8~25%.
4.21 Pinhole electrode technology, the powder sample is mixed with appropriate additives in a certain proportion, and filled into a pinhole graphite electrode (see SJ/Z3206.6-89 (shape and size of graphite electrode for emission spectroscopy analysis). The sample is excited by a DC arc anode or an AC arc. It is suitable for silicates, ceramics, pure elements and their compounds with relatively simple spectra. Such as: determination of impurities in matrices such as boron, carbon, aluminum, silicon, zinc, vanadium, germanium, selenium, indium, tin, antimony, tellurium, thallium, lead, and bismuth.
4.2.2 Fractional distillation evaporation technology, the powdered sample and the appropriate carrier are mixed evenly in a certain proportion, a certain amount of sample is weighed and filled tightly with a special filling tool or pressed into a block in a mold and placed in a cup-shaped electrode (see SJ/23206.6-89). The anode excitation of the DC arc causes the impurities and the matrix to evaporate separately to suppress the interference of the matrix spectrum line on the spectrum line of the analyzed element. It is suitable for elements and their compounds with complex spectrum lines. For example, the determination of volatile and medium volatile impurities in matrices such as tungsten, molybdenum, molybdenum, niobium, hafnium, titanium, cobalt, zirconium, vanadium, cerium, and needle. -2
SJ/Z3206.12-89Www.bzxZ.net
4.2.3 Spherical arc technique, weigh a certain mass of metal chips or oxide powders of certain metals, press them into blocks in a die, place them on the surface of a stone shadow electrode (see SJ/Z3206.689), form a spherical solitary light discharge in direct current, and the sample is excited at the anode to determine the volatile elements, and at the cathode to determine the medium volatile elements. It can be used to determine impurities in matrices such as copper, iron, cobalt, gold, and silver. 4.3 Solution method, dissolve the sample in an appropriate solvent, and keep the matrix at a certain concentration in the solution according to the detection limit required for the analysis. Use the solution to synthesize the standard sample, in which the matrix concentration, acidity, and anion type should be consistent with the analysis sample, and mix well before use. The detection limit of impurities is 10~4~10-%, and the relative standard deviation of the analysis is 10~20%.
4.3.1 Solution dry residue technology, a certain amount of solution is dripped on the surface of a flat electrode (see S3/Z2306.6) to which a sealing agent (such as a benzene solution of polystyrene) has been added in advance. Dry under an infrared lamp and excite a pair of sample-carrying electrodes in an alternating current or a high-voltage spark. The solution can also be dripped directly on a pure copper flat electrode and excited by a high-voltage spark (called spark technology).
This research analysis technology can also be used in chemical spectral analysis to determine the impurity concentration after separating the matrix, thereby analyzing high-purity materials.
4.3.2 Plasma technology, inductance combined with high-frequency plasma excitation source, is a technology that has been successfully developed and applied in recent years. It has the advantages of low detection limit, high accuracy, small matrix effect, and wide linear range of analysis. When the matrix and impurities of the sample can exist in a solution state, plasma analysis can be used. Additional remarks
This standard was proposed by the Electronic Standardization Research Institute of the Ministry of Machinery and Electronics Industry. This standard was drafted by the 774th Factory and the Standardization Research Institute of the Ministry of Machinery and Electronics Industry. The drafters of this standard were Wang Jinxue, Zhao Changchun and Huang Wenyu.
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.