Appraisement method for stamp-forming characteristics of galvanized steel sheet

Abstract

The present invention provides a press forming evaluation method of a galvanized steel sheet, which rapidly evaluates the press formability of a galvanized steel sheet having an oxide film with a thickness of 10 nm to 100 nm on a plated surface layer in a non-destructive manner. A specific solution is characterized in that it has: a process of irradiating X-rays to a galvanized steel sheet; passing through a spectroscopic crystal having a diffraction angle difference of 2 degrees or more between the primary diffraction line of Kα rays of oxygen and the secondary rays of Lβ rays of zinc, The process of spectroscopically analyzing the fluorescent X-rays excited and released in the above process; the process of detecting the X-ray of the primary diffraction line of the Kα ray that is mainly composed of oxygen in the above spectroscopic process with a detector; The energy level of the primary diffraction line of the Kα ray is taken as the reference (100%), and the window width of the wave height analyzer is adjusted so that the energy level of the X-ray within the range of ±25% to ±75% is obtained from the above detection A process of separating the X-rays mainly including the primary diffraction line of the Kα ray detected in the process; a process of measuring the intensity of the X-rays separated in the above process; and based on the X-ray measured in the above process The process of evaluating the intensity of radiation and the press formability of galvanized steel sheets.

Description

technical field [0001] The present invention relates to a technique for rapidly evaluating the press formability of a galvanized steel sheet by rapidly measuring the amount of an oxide film with a thickness of 10 nm to 100 nm formed on the surface of a galvanized steel sheet in a non-destructive manner. Background technique [0002] In the product fields of steel, semiconductors, and displays, surface coatings with a thickness of tens to hundreds of nm sometimes become a dominant factor in product characteristics. In the field of iron and steel products, the surface film with a thickness of tens to hundreds of nm sometimes becomes the dominant factor in the stamping characteristics of the product. In recent years, steel sheets used in automobiles and home appliances have been frequently plated with zinc from the viewpoint of high corrosion resistance. Strict parts are likely to cause the problem of stamping cracks in the steel plate. A method of improving the stamping form...

AI Technical Summary

Problems solved by technology

However, for example, in the case of, for example, alloyed hot-dip galvanized steel sheets, when there are roughness caused by temper rolling or fine roughness caused by alloying reaction on the base plated steel sheet, it is difficult to ensure the measurement accuracy of the film thickness.

[0023] In this way, the current situation is that the technology that can measure the thickness of the ultra-thin oxide film formed on the surface layer of the hot-dip galvanized steel sheet at a minimum speed without delaying the shipment is not yet known.

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