Method for preparing metal structural part with complex shape through 3D cold printing

Abstract

The invention discloses a method for preparing a metal structural part with the complex shape through 3D cold printing, and belongs to the technical field of cold isostatic pressing forming. The method comprises the following steps that a 3D cold printing method is adopted to print a cold isostatic sheath green body of a glucose high polymer with a complex shape, and then a layer of colloid thin layer coats the surface of the green body so as to obtain a novel cold isostatic pressing sheath; metal powder is mixed with an organic liquid, a slurry is prepared and is poured into the novel sheathuntil the powder body completely fills the sheath, then cold isostatic pressing and vacuum sintering are carried out, so that the metal structural part with the complex shape is prepared. According tothe method, in the cold isostatic pressing process, the organic liquid in the slurry is absorbed through the porous loose sheath, so that the metal powder fully and uniformly fills the sheath, the resilience is small in the cold isostatic pressing process, stress concentration is avoided, the shape of a pressed green body of the structural part with the complex shape can be guaranteed to be complete, the pressed green body is free of breakage, and the method is high in yield and beneficial to obtaining the metal structural part with the complex shape and integrity and high-strength.

Description

technical field [0001] The invention belongs to the field of cold isostatic pressing, and provides a method for preparing complex-shaped metal structural parts by 3D cold printing. Background technique [0002] Cold isostatic pressing (Cold Isostatic Pressing, CIP) is an important powder metallurgy forming technology. It is a method of compressing and forming powder by transmitting isotropic pressure through a fluid medium at room temperature. It can process high-temperature alloy materials, hard alloy materials, and ceramic materials that are difficult to manufacture under conventional solidification conditions. Compared with conventional forming technology, cold isostatic pressing has the advantages of uniform product structure, no component segregation, high material utilization rate, high green density and low cost. Through CIP, the density of the workpiece can be greatly improved and the strength of the workpiece can be increased. Cold isostatic pressing is generally ...

AI Technical Summary

Problems solved by technology

However, directly filling the powder into the sheath not only requires high powder fluidity, but also increases the cost of raw materials, and is also prone to uneven and incomplete powder filling, which cannot be isostatically pressed, resulting in uneven green compact density. Even the phenomenon of green body breaking occurs, the yield rate is low, resulting in waste of raw materials and high cost, and it is difficult to prepare complex shapes and multi-symmetrical axis parts

[0004] At present, due to the limitation of the shape of the cold isostatic sheath and the filling powder, the cold isostatic pressing technology is only limited to the preparation of blocks or hollow thick-walled blanks with regular and simple shapes, and it is impossible to prepare workpieces with irregular and complex shapes.

Therefore, a method of 3D cold printing is used to prepare metal structural parts of complex shapes, using 3D cold printing technology combined with cold isostatic pressing technology, through 3D cold printing loose and porous complex shape cold isostatic pressing envelopes, and then using injection The powder-filled slurry method fills the sheath with powder, and finally obtains complex-shaped metal components after cold isostatic pressing, which is of great significance to solve the problems of difficult forming of complex shapes and low yield of pressed parts.

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