A core structure for sand casting, a manufacturing method, and a mold comprising the core

Abstract

The invention discloses a core structure for sand casting, a manufacturing method and a mold including the core, which comprises a core body, the interior of the core body is hollow, and a support structure is arranged inside the core body. The structure is an array structure, and the array is formed by connecting a plurality of unit cells together. The sand volume and weight of the hollow core are smaller than those of the solid core. Under the same external structure and size, the experiment found that the weight of the hollow core is 3Kg lighter than that of the solid core, and the amount of sand used is about 83% of the previous one. The heat dissipation of the hollow sand mold is better than that of the solid core. Under the same casting conditions, the experiment found that the heating rate of the solid core is significantly higher than that of the hollow core supported by the unit body. Under the condition of the same solidification shrinkage force, the deformation of the hollow core supported by the proposed unit body is smaller than that of the hollow core of the same size truss structure.

Description

technical field [0001] The invention relates to a core structure for sand casting, a manufacturing method and a mold comprising the core, and belongs to the field of casting. Background technique [0002] The core is used to form the internal structure of the casting during casting, and its composition is usually raw sand and binder. According to whether the inside is hollow structure, the core can be divided into solid structure and hollow structure. At present, the core structure used in factory production is a solid structure, which has the disadvantages of large sand consumption, large sand discharge, poor heat dissipation conditions inside the core, and high labor intensity of workers. Especially in the production of large solid cores, the above problems Especially prominent. The core with hollow structure can avoid the above problems, but the manufacturing process is relatively complicated. At present, the manufacturing method of the core is mostly hand-made or mach...

AI Technical Summary

Problems solved by technology

[0004] There have been researches on hollow cores at home and abroad, but most of the internal support structures used are truss structures. For example, in the research on hollow sand molds based on 3D printing carried out by Shangguan Haolong of Tsinghua University in 2018, truss structures were used as internal supports. structure, but the surface of the structure and the connection nodes are not smooth transitions, and there are a large number of stress concentration points, which are more prone to collapse and cracks when receiving external forces, resulting in internal support when casting castings with large shrinkage such as cast steel. collapse phenomenon, the strength of the truss support structure needs to be further improved

If in order to increase the strength, it is necessary to increase the wall thickness or thicken the truss, which will lead to poor internal heat dissipation conditions and cannot take advantage of the good heat dissipation of the hollow core

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