High-pressure directional solidification material and method thereof

Abstract

The invention discloses a high-pressure directional solidification material and a preparation method thereof. The preparation method comprises the following steps that an aluminum block and a nickel block are heated, melted and evenly mixed, cutting is conducted after cooling, shear marks are removed through grinding, and an Al-Ni alloy sample is obtained after cleaning and drying; the Al-Ni alloy samples are assembled into an assembly body and placed in a pressure cavity of a hydraulic machine, the space between the assembly body and the inner wall of the pressure cavity is filled with pyrophyllite, and the pyrophyllite and the assembly body jointly form an assembly block; the assembled block is pressurized to 1-3 GPa through the hydraulic machine, and meanwhile, after a conductive ring is electrified, the Al-Ni alloy sample is heated to 800-1000 DEG C through a carbon heating body under the conductive effect of elemental molybdenum; keeping the temperature and the pressure to realize the high-pressure directional solidification process of the Al-Ni alloy sample to obtain a reaction body; and reducing the temperature of the reaction body to normal temperature, and releasing the pressure to obtain the high-pressure directional solidification material. According to the method, the near-directional solidification process of the alloy is researched under the GPa-level condition, and the method has great significance in exploring and establishing some basic theories in the high-pressure solidification process and expanding the possibility of a preparation method of a novel high-pressure solidification material.

Description

technical field [0001] The invention belongs to the technical field of non-equilibrium solidification, and in particular relates to a high-pressure directional solidification material and a method thereof. Background technique [0002] A casting process in which a temperature gradient in a specific direction is established in the casting shell to make the molten alloy solidify in the direction opposite to the heat flow in accordance with the required crystallographic orientation. The most prominent achievement of directional solidification technology is its application in the aviation industry. A temperature gradient exists in every solidification process. For alloys with a certain solidification range, a mushy region characterized by partial melting will inevitably be produced during cooling. Furthermore, the solidified microstructure (i.e., shape, size, composition) formed in the mushy region largely determines the final organization and properties of the material. More...

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Problems solved by technology

[0004] At present, the domestic six-sided high-temperature and high-pressure equipment can manufacture larger-sized samples such as Φ20mm×18mm, but its larger cavity will cause uneven temperature and pressure distribution during the high-pressure solidification process of the sample. Therefore, according to the prepared sample Microstructure is not accurate when establishing high-pressure solidification theory

However, most of the existing solidification theories are based on directional solidification methods. Therefore, it is urgent to provide a technical solution that can reasonably utilize the characteristics of high-pressure solidification pressure and uneven temperature distribution to achieve near-directional solidification under high pressure.

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