Preparation method of iron-based continuous casting profile based on graphite nodule ultra-fining

Abstract

The invention discloses a preparation method of an iron-based continuous casting profile based on graphite nodule ultra-fining. A proper nucleating agent and a proper nodulizer are added into molten iron in the continuous casting process of an iron-based profile, so that the nucleation rate of graphite in the solidification process of the molten iron is far greater than the nucleation rate of the graphite when a conventional nucleating agent and nodulizer are used for inoculation and spheroidizing treatment; and graphite nodules in the continuous casting iron profile are ultra-refined, so that the density number of the graphite nodules at the position, 50 mm from the outside to the inside, of the continuous casting iron profile is not less than 500 / mm2 and is far larger than the density number of the graphite nodules obtained after the nodular cast iron profile is treated through the conventional nucleating agent and nodulizer at present. Due to the fact that the density number of the graphite nodules is greatly increased, the diameter of the graphite nodules in the continuous casting iron profile is greatly reduced, the roundness and the distribution uniformity of the graphite nodules are greatly improved, and therefore damage to a metal matrix caused by irregular shapes and uneven distribution of the graphite nodules is remarkably reduced, and therefore, the related performance of the iron profile is obviously improved.

Description

technical field [0001] The invention belongs to the technical field of manufacturing cast iron profiles, and in particular relates to a method for preparing iron-based continuous casting profiles based on ultrafine graphite balls. Background technique [0002] Due to the spherical shape of graphite in ductile iron, it has higher strength and better toughness than other cast irons, and its mechanical properties can be further improved by heat treatment. However, the spheroidization rate of graphite in ductile iron and the size of graphite spheres have a crucial influence on the mechanical properties of cast iron. For example, with the reduction of graphite ball diameter, the strength, plasticity, toughness, fatigue performance and oxidation resistance of cast iron will be improved. However, in order to obtain spherical graphite, the existing nodular cast iron profiles are generally hypereutectic. Therefore, the solidification structure generally contains coarse primary graph...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a method for preparing iron-based continuous casting profiles based on ultra-fine graphite balls, which solves the problems caused by the slow cooling rate of the core and the decline of inoculants and nodularizers in the existing continuous casting ductile iron production process. The problem of thick graphite nodules in the core, uneven size distribution and low density of graphite nodules, etc., realizes the ultrafine and high density of graphite nodules in continuous casting iron profiles, thereby improving the mechanical properties of continuous casting nodular cast iron and improving its application performance