Research methods of high quality steel

At present, traditional inspection methods are still widely used in steel mills, the most important of which are: low acid inspection; Fracture inspection; Sulfur imprinting test; Tower test; Ultrasonic inspection and metallographic examination. Among the above inspection methods, all are macroscopic inspection methods except high-magnification metallographic examination.

The so-called macro inspection is the inspection with naked eyes or with the help of a magnifying glass less than 10 times. Macro inspection (including macro acid leaching inspection, fracture inspection and tower inspection) can directly detect the defects in steel during smelting, casting, hot working and heat treatment, and has the advantages of simple process, low requirements for inspection equipment, convenient operation and low cost. Therefore, metallographic examination is widely used at home and abroad to detect macro-structural defects in steel, including decarburization, carbide network, carbide band, carbide liquid precipitation and carbide.