Pure-nickel metallographic etchant and corroding method using same

Abstract

The invention provides pure-nickel metallographic etchant and a corroding method using the same. The pure-nickel metallographic etchant is prepared by mixing distilled water, 65-68% concentrated nitric acid and 99.5% glacial acetic acid. The corroding method using the pure-nickel metallographic etchant includes: preparing a pure-nickel sample, using the etchant to perform metallographic surface corrosion, observing with a metallographic microscope, and analyzing a metallographic structure through metallographic structure morphology and crystal boundary observation. The pure-nickel metallographic etchant has the advantages that the glacial acetic acid is added according to strict proportion and appropriate amount and acid-water mixture is added, the corroded metallographic sample is allowed to have the clear metallographic structure, the etchant can fast and effectively erode the metallographic structure of the sample, the clear metallographic structure of the pure-nickel metallographic sample can be observed after corrosion, and evident boundary and contrast exist among different phases.

Description

technical field [0001] The invention belongs to the field of chemical industry and relates to a metal metallographic corrosion solution, in particular to a preparation and corrosion method of a pure nickel metallographic corrosion solution. Background technique [0002] Pure nickel is mainly used in military industry, aerospace, petrochemical industry, and marine industry. It has a wide range of uses, so its research history is relatively long. There are relatively few data. Metallographic detection and analysis is the basis of nickel material research. Through metallographic structure analysis, it can be observed whether the phase composition and grain size of the corroded sample are uniform, and non-metallic compound slag inclusions, pores, porosity, cracks, cracks, etc. can also be observed. Defects such as overburning can also be used to judge whether the product production process is perfect. Through metallographic analysis to help find the cause of product defects an...

AI Technical Summary

Problems solved by technology

If the corrosion solution is not selected properly, the metallographic structure of the sample will not be corroded; even if a suitable type of acid is selected, but the proportion of the preparation is too high, it is easy to form over-corrosion, the grain boundaries and grains are black, and no clear crystals can be observed at all. Grain boundary and grain size, and the contrast between phases cannot be observed. If the preparation ratio is too low, the grain boundary will not be corroded at all, and the microstructure will not be observed.

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