A kind of contrast detection method of high-purity magnesium purity

Abstract

The invention discloses a purity contrast detection method of high-purity magnesium. Firstly, prepare a borax-sodium hydroxide buffer solution, then dilute and heat it, and set aside; then, after sanding several pure magnesiums with known impurity contents, they are ultrasonically cleaned with ultra-pure water to obtain several pure magnesiums with different purities. Magnesium sample; then, measure a certain amount of the above-mentioned buffer solution, and add a certain amount of sodium chloride; after the pH of the obtained solution is stable, put several pure magnesium samples of different purity into different containers, and start to monitor the pH at the same time With the change of time, the pH-t change curve is obtained; by comparing the change curve of the pure magnesium sample to be tested with the known purity sample, the time required for each sample to reach pH 10.8 can be obtained, and the pure magnesium to be tested can be obtained. The purity range of the sample.

Description

technical field [0001] The invention relates to the field of magnesium purity detection, in particular to a high-purity magnesium purity contrast detection method. Background technique [0002] Impurities in pure magnesium have a great influence on its corrosion resistance, the higher the purity of magnesium, the better the corrosion resistance. But, when the purity is high to a certain level (greater than 99.95%), the detection problem of purity is oncoming, the detection cost of glow discharge mass spectrometer (GDMS) is too high, and the detection cost of inductively coupled plasma mass spectrometer (ICP-MS) The detection cycle is long, and the detection accuracy is greatly affected by the operating level of the operator. A relatively simple and common method is usually to soak pure magnesium in 3.5wt.% sodium chloride solution and count the change of its hydrogen evolution amount (convert the hydrogen evolution rate to the matrix corrosion rate). There are several prob...

AI Technical Summary

Problems solved by technology

There are several problems with this method. First, in the test, the inverted funnel will stick a part of the hydrogen gas. Therefore, for high-purity magnesium with a small amount of hydrogen evolution, the statistics are inaccurate and there are large errors. It is impossible to compare the corrosion rate with this method.

Secondly, this method records the trend of hydrogen evolution over time, and the time period required for high-purity magnesium is too long (up to more than one week)

Finally, matrix structure defects are also an important factor to accelerate corrosion, but they are often not easy to be found, which eventually leads to inaccurate statistics of hydrogen evolution results

Therefore, for high-purity magnesium smelting units, it is difficult for the above-mentioned methods to obtain the purity information of high-purity magnesium quickly, at low cost, and accurately.

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