Freeze-etching agent of ultra-low-carbon steel casting billet macrograph grain structure, and preparation method thereof

Abstract

The invention discloses a freeze-etching agent of ultra-low-carbon steel casting billet macrograph grain structure, and a preparation method thereof. The freeze-etching agent is prepared from materials of: 30 to 50g of ferric chloride, 0.5 to 1.2g of stannous chloride, 2 to 3 parts of trinitrophenol, 10 to 20ml of sodium alkyl phenyl sulfonate, 200 to 500ml of absolute alcohol, and 600 to 1000ml of hydrochloric acid. Solid agents of the formulation are mixed and placed into a glass vessel according to the ratio; 1500 to 2000ml of distilled water is divided into two parts; one part is added to the solid mixed agents, and the other part is preserved for later use; absolute alcohol is added to the preserved part of distilled water; hydrochloric acid is added to the alcohol solution; sodium alkyl phenyl sulfonate is added to the aqueous solution containing agents such as ferric chloride, and the mixture is uniformly stirred; the alcohol + hydrochloric acid solution is then added to the aqueous solution containing the agents such as ferric chloride; the solution is sufficiently stirred, such that the freeze-etching agent is prepared. With the freeze-etching agent, the form of the ultra-low-carbon continuous casting steel billet macrograph grain structure can be clearly shown. The freeze-etching agent provided by the invention has advantages of high detection speed, low pollution, and convenient operation. Also, the freeze-etching agent is energy-saving.

Description

technical field [0001] The patent of the present invention relates to the field of metallurgical analysis, in particular to a corrosion test for displaying the low-magnification grain structure of metallurgical continuous casting billets. Background technique [0002] The low-magnification inspection methods of steel include hot acid etching method, cold acid etching method, electrolytic corrosion method, and sulfur printing inspection method. Each of these methods shows its own characteristics in practical application. Due to its strong corrosion ability, the hot acid etching method is used to display the low-magnification structural defects of steel, its shape is clear, and the defects are completely exposed. However, the crystalline structure of some low carbon steel continuous casting slabs is insufficient. And the hot acid corrosion method pollutes the environment and consumes a lot of energy. The sulfur print test method mainly reflects the segregation form of sulfu...

AI Technical Summary

Problems solved by technology

[0010] Aiming at the problem that the prior art cannot inspect the low-magnification grain morphology of the original size sample of the ultra-low carbon steel continuous casting slab, the invention discloses a low-magnification crystal grain display for the ultra-low carbon steel continuous casting slab that can be selectively corroded. Corrosive agent in granular form

Solved the problem that hot acid etching, general cold acid etching, and sulfur printing methods cannot fully display the low-magnification grain structure of steel billets with carbon content <0.03

Images