Efficient quantitative characterization method for complex-phase steel body-centered cubic structure phase

Abstract

The invention provides an efficient quantitative characterization method for a complex-phase steel body-centered cubic structure phase, and belongs to the technical field of steel and iron material microscopic structure determination. The method comprises the following steps: firstly, preparing a metallographic sample, then carrying out constant-voltage electrolysis on the sample in an electrolyte, carrying out EBSD characterization on the electrolyzed sample, and selecting a step size which is 1 / 10 of the average grain size of the sample; the method comprises the following steps: carrying out EBSD original data processing by using OIM commercial software, independently exporting an Image Quality distribution table of a body-centered cubic structure phase, importing the obtained data into Excel for IQ numerical value standardization processing, importing the data into origin for Gauss multi-peak fitting, and finally obtaining the volume fractions of ferrite, bainite and martensite in a sample through the integral area proportion and position interval of each peak. According to the method, efficient and accurate quantitative characterization of the phase proportions of various body-centered cubic structures in the complex phase steel is achieved, and a new shortcut is provided for rapid and accurate quantitative analysis of multi-phase structures in research, development and analysis of complex phase steel materials.

Description

technical field [0001] The invention relates to the technical field of microstructure measurement of iron and steel materials, in particular to an efficient quantitative characterization method for complex-phase steel body-centered cubic structure phases. Background technique [0002] Complex phase steel (Complex Phase steel) is a representative of the third generation of advanced high-strength steel for automobiles. Because of the bainite-based complex phase steel mixed with a small amount of hard phases (martensite and M / A islands), the deformation coordination between the phases of the complex phase steel Strong, with excellent hole expansion performance (hole expansion rate 50% ~ 85%) and high yield ratio (0.85 ~ 0.9), has attracted the attention of the field of automotive lightweight, widely used in chassis parts (torsion beam , control arms, etc.) and seat accessories (side panels, slide rails). Due to the mixing of three or more phase components, the metallographic s...

AI Technical Summary

Problems solved by technology

[0003] At present, the difficulty of using quantitative metallographic analysis technology lies in the accurate identification and rapid extraction of characteristic structures. Although the commonly used color metallographic method is fast and intuitive, it is not suitable for complex phase steel due to the difficulty in obtaining experimental reagents, unstable techniques and low resolution. Quantitative characterization of the tissue

The traditional EBSD method can realize the resolution and quantitative statistics of the biphasic structure by setting the threshold, but it still cannot meet the quantitative characterization requirements for various body-centered cubic structure phase structures.

Images