Method for composite electromagnetic continuous-casting high-oriented ultra-fine grained materials

Abstract

The invention relates to a method for continuously producing high-orientated fine-grained metallic material in complex electromagnetic field, pertaining to the technical field of metal casting. The method of the invention is outlined as follows: a pair of self-cooling electrodes are inserted into the upper part of metal melts in a crystallizer, and is electrified with AC power, and a DC induction coil is arranged outside the crystallizer and electrified with DC current to generate a DC magnetic field. The self-cooling electrodes induce the melts near the electrodes to form a crystal core, and combine with electromagnetic oscillation to eject the crystal core into the metal melts, then a core body for the later metal solidification. The crystal core is magnetic orientated during the process of sedimentation, and eventually metal material with highly-orientated fine crystal structure is obtained. The AC current frequency range adopted by the invention is 10 to 10000Hz, AC current intensity range is 0 to 10000A, and magnetic field intensity generated by the DC current is 0 to 10 T and can be continuously tuned. The high-orientated fine-grained metallic material prepared by the invention has uniform casting organizations and can substantially improve the performance and quality of the metal material.

Description

technical field [0001] The invention relates to a method and a device for continuously casting highly oriented fine-grained metal materials under the action of a composite electromagnetic field, belonging to the technical field of metal casting technology. Background technique [0002] The grain size of the material has an important influence on the performance of the material. The strength, hardness, plasticity and toughness of the metal material increase with the grain refinement. Therefore, controlling the grain size of the material has important practical significance. Grain refinement can be roughly divided into thermodynamic control mode, chemical control mode and kinetic control mode according to the different modes of action on the melt. [0003] The thermodynamic method is mainly to control the cooling of the melt cold body to obtain a large degree of subcooling. According to the principle of classical crystallography, the nucleation rate of metal crystallization i...

AI Technical Summary

Problems solved by technology

In practical applications, people often need anisotropic materials. In order to obtain anisotropic materials, people usually use unidirectional solidification to obtain highly oriented columnar structures, which greatly improves the longitudinal mechanical properties of materials. , but the mechanical properties in the transverse direction are not satisfactory. For this reason, people have invented single crystal casting technology to obtain single crystal materials, thereby improving the isotropic properties of materials. However, single crystal technology cannot use all alloy systems. very demanding and expensive

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