Electromagnetic semi-continuous casting device and method for alloy ingot with high casting stress

Abstract

The invention belongs to the technical field of casting, in particular to an electromagnetic semi-continuous casting device for alloy ingots with high casting stress and an ingot casting method using the device. The electromagnetic semi-continuous casting device mainly includes a shunt, a mold and a dummy head, and the mold includes a mold inner sleeve, a cold water tank, a coil and a bottom bracket. Under the condition that the amount of cold water is constant, a cold water tank with double rows of different-diameter cross water holes is used to make the first cold water appear double water streams, thereby reducing the cooling rate of the alloy melt at the contact point between the first cold water and the inner sleeve of the crystallizer , thereby reducing the chance of cracking. Through the setting of the distance between the double drainage holes, the cooling intensity during casting can be controlled, which helps to improve the surface quality of the ingot. The use of the diverter groove in the device of the present invention can also effectively reduce the temperature gradient and casting stress at the center and edge of the slab, thereby reducing the possibility of cracking of the ingot. The electromagnetic semi-continuous casting device in the present invention can also realize the production of products within a certain specification range by changing the specifications of the mold inner sleeve.

Description

technical field [0001] The invention belongs to the technical field of casting, in particular to an electromagnetic semi-continuous casting device for alloy ingots with high casting stress and an ingot casting method using the device. Background technique [0002] Taking magnesium alloys as an example, high casting stress alloys mainly include Mg-RE alloys and Mg-Zn-Zr alloys, and Mg-RE alloys are magnesium alloys used at temperatures above 200 °C. Commonly used rare earth elements are Y, Nd, Ce, Dy, Gd, etc. Adding rare earth elements is the most direct way to improve the properties of magnesium alloys, which can effectively improve the mechanical properties of magnesium alloys at room temperature and high temperature, so rare earth elements are widely used in magnesium alloys. Mg-Zn-Zr series alloys refer to magnesium alloys added with zinc and zirconium, and are considered to be one of the magnesium alloys with the best comprehensive properties. According to ASTM standa...

AI Technical Summary

Problems solved by technology

[0007] However, the form of cooling intensity of ordinary semi-continuous casting crystallizers is relatively simple, and the first cooling (first cooling, second cooling, and third cooling in the present invention are the abbreviations of primary cooling, secondary cooling, and third cooling, the same below) water is sprayed into the inner sleeve of the crystallizer. , the cooling rate of the metal melt in the inner sleeve at the contact position is relatively large, and the temperature drop is severe, resulting in rapid grain growth and easy growth into columnar crystals; and, because the cooling of the alloy melt at the primary cooling water injection is faster, At the same time, due to the difference in solidification sequence, serious macro-segregation and internal stress will cause wrinkles on the surface of the ingot, which will affect the surface quality of the ingot, and will greatly reduce the yield of the ingot in actual production. Therefore, How to reduce the cooling rate of the alloy melt in the high temperature stage by controlling the first cooling, improve the structure uniformity and refinement effect of the cast ingot, and improve the metallurgical surface quality of the cast ingot is an urgent problem to be solved in the magnesium alloy production industry

[0008] Chinese Patent CN108637200A "Semi-continuous Casting Device for Large Magnesium Alloy Slab Ingot", Chinese Patent CN108405821A "Casting Device and Method for Large Magnesium Alloy Flat Ingot without Cracks", Chinese Patent CN110125358A "An Electromagnetic Semi-continuous Casting Device for Nonferrous Metals and Their Alloys" "Casting Device" respectively discloses a semi-continuous casting device and method for a large-size magnesium alloy long flat ingot, a casting device and method for a large-size magnesium alloy flat ingot without cracks, and an electromagnetic semi-continuous casting device for non-ferrous metals and their alloys , but one of the cooling holes is a single drainage hole, the amount of cooling water is relatively large, the cooling speed of the melt in the part where the inner sleeve is just in contact with the crystallizer melt is too fast, the crystal grains grow faster, and the columnar crystals are easy to grow

Chinese patent CN110405170A "A low-cooling electromagnetic semi-continuous casting device and method" discloses a low-cooling electromagnetic semi-continuous casting device and method. Although the first cooling and the third cooling can be independently adjusted, the first cooling water is injected into The cooling rate produced by the outer wall of the inner sleeve is relatively large, and the temperature drop is severe, which leads to rapid growth of grains, and it is easy to grow into columnar grains.

[0009] For alloys with high casting stress, traditional semi-continuous casting equipment is mainly used to produce round ingots, and the production is difficult, so it is more difficult to produce large flat ingots with a certain width-to-thickness ratio

Images