Method for detecting and evaluating continuously cast steel billet primary cooling effects

Abstract

The invention relates to a method for detecting and evaluating continuously cast steel billet primary cooling effects. The method includes 1, taking samples; 2, preparing and treating test specimens, to be more specific, accurately grinding and machining detection surfaces of test specimen blocks, corroding the detection surfaces of the test specimen blocks in nitric acid solution and absolute ethyl alcohol corrosive agents with the concentration equal to or higher than 96% for approximately 30-120 seconds, taking the detection surfaces of the test specimens out of the nitric acid solution and absolute ethyl alcohol corrosive agents, washing the detection surfaces of the test specimens by the aid of distilled water, cleaning the detection surfaces of the test specimens by the aid of absolute ethyl alcohol and then drying the detection surfaces of the test specimens; 3, imaging the test specimens, to be more specific, observing the detection surfaces of the treated test specimens by the aid of a research-grade stereo microscope under appropriate multiple conditions and measuring and photographing typical positions; 4, evaluating the primary cooling effects, to be more specific, observing and computing the thicknesses of chilled fine grain layers of cast billets and the sizes and the morphology of each single crystalline grain according to obtained images, analyzing the appropriateness and the uniformity of the thicknesses of the chilled fine grain layers and evaluating the primary cooling effects. The method has the advantages that the clear images of solidification structures of samples can be quickly and visually obtained, the thicknesses of the chilled fine grain layers of the cast billets can be further measured and analyzed according to the images, and accordingly the continuous casting primary cooling effects can be reliably and comprehensively analyzed and evaluated.

Description

technical field [0001] The invention relates to a method for detecting and evaluating the first-cooling effect in the production process of continuous casting steel slabs. Background technique [0002] At present, in the continuous casting of steel billets, the evaluation of the first cooling effect is mostly by means of acid leaching and sulfur printing, and there is no intuitive detection and detection of the suitability and distribution uniformity of the fine-grained layer thickness of the continuous casting billet chilling. As for the evaluation method, with the improvement of continuous casting technology, there are no obvious defects visible to the naked eye in the low-magnification inspection of the edge of the continuous casting slab, and the low-magnification inspection methods of acid leaching and sulfur printing can no longer meet the requirements of more in-depth analysis and evaluation. In view of the above situation and the urgent requirement for the evaluation...

AI Technical Summary

Problems solved by technology

[0002] At present, in the continuous casting of steel billets, the evaluation of the first cooling effect is mostly by means of acid leaching and sulfur printing, and there is no intuitive detection and detection of the suitability and distribution uniformity of the fine-grained layer thickness of the continuous casting billet chilling. Evaluation method, with the improvement of continuous casting technology, the edge of the continuous casting slab has no obvious defects visible to the naked eye in low-magnification detection, and the low-magnification detection methods of acid leaching and sulfur printing can no longer meet the requirements of more in-depth analysis and evaluation