Preparation method of flexible gradient porous metal

Abstract

A preparation method of flexible gradient porous metal comprises the steps that casting sand is poured into gradient polystyrene foam, a porous metal mold is manufactured, molten liquid of metal with small hardness is injected into the porous metal mold, and an original gradient porous metal framework is formed; then fixing on a vibration table for vibration, so that gaps are formed around the framework in the casting sand; and then molten metal with high hardness is further poured, so that the flexible gradient porous metal with different specifications is obtained. The flexible gradient through hole porous metal is prepared by repeatedly using an investment casting method, so that the production cost is greatly reduced, the preparation speed is increased, and the flow boiling heat exchange performance can be greatly improved.

Description

technical field

[0001] The invention relates to a technique in the field of composite materials, in particular to a method for preparing a flexible gradient porous metal. Background technique

[0002] Gradient through-hole porous metal has a dense metal skeleton, with winding and complex communication channels inside, a large heat transfer specific surface area, and a small relative density. The market application prospects in the fields of environmental chemical industry, energy saving and emission reduction are very bright. However, when the gradient porous metal is used in the tube to enhance flow boiling heat transfer, due to the existence of the metal skeleton perpendicular to the direction of the flow field, the flow resistance increases, the pump work increases, and the energy consumption increases. If the gradient porous metal skeleton is designed with reference to the cross-sectional structure of bamboo, and the metal material with lower hardness is used inside, an...

Examples

Embodiment 1

[0024] The preparation process of this embodiment is as follows:

[0025] The first step is to pour foundry sand into gradient polystyrene foam to form a mold.

[0026] In the second step, in an argon atmosphere, heat to 250°C in a muffle furnace to melt tin into a liquid, and then inject the liquid tin into a gradient polystyrene foam mold. On cooling, the original gradient tin foam is formed.

[0027] The third step is to vibrate the gradient tin foam from left to right, back and forth, up and down in a small range to form gaps around the tin wire skeleton in the foundry sand.

[0028] Step 4: In an argon environment, heat to 670°C in a muffle furnace to melt the aluminum into a liquid, and then quickly inject the liquid aluminum into the gaps around the original gradient tin foam skeleton. Cool to form a flexible aluminum-tin gradient porous metal with a porosity of 0.98 and a pore density gradient of 20PPI-60PPI. Such as figure 1 shown.

[0029] Through simulation cal...

Embodiment 2

[0031] The preparation process of this embodiment is as follows:

[0032] The first step is to pour foundry sand into gradient polystyrene foam to form a mold.

[0033] In the second step, in an argon atmosphere, heat to 350°C in a muffle furnace to melt lead into a liquid, and then inject the liquid lead into a gradient polystyrene foam mold. On cooling, the original gradient tin foam is formed.

[0034] The third step is to vibrate the gradient aluminum foam left, right, front, back, up and down in a small range to form gaps around the aluminum wire skeleton in the foundry sand.

[0035] Step 4: In an argon environment, heat up to 1100°C in a muffle furnace to melt copper into liquid, and then quickly inject liquid copper into the voids around the original gradient lead foam skeleton. Cool to form a flexible copper-lead gradient porous metal with a porosity of 0.98 and 20PPI-60PPI. Such as figure 2 shown.

[0036] Through simulation calculation, it is found that under ...

technical field

[0001] The invention relates to a technique in the field of composite materials, in particular to a method for preparing a flexible gradient porous metal. Background technique

[0002] Gradient through-hole porous metal has a dense metal skeleton, with winding and complex communication channels inside, a large heat transfer specific surface area, and a small relative density. The market application prospects in the fields of environmental chemical industry, energy saving and emission reduction are very bright. However, when the gradient porous metal is used in the tube to enhance flow boiling heat transfer, due to the existence of the metal skeleton perpendicular to the direction of the flow field, the flow resistance increases, the pump work increases, and the energy consumption increases. If the gradient porous metal skeleton is designed with reference to the cross-sectional structure of bamboo, and the metal material with lower hardness is used inside, an...

Examples

Embodiment 1

[0024] The preparation process of this embodiment is as follows:

[0025] The first step is to pour foundry sand into gradient polystyrene foam to form a mold.

[0026] In the second step, in an argon atmosphere, heat to 250°C in a muffle furnace to melt tin into a liquid, and then inject the liquid tin into a gradient polystyrene foam mold. On cooling, the original gradient tin foam is formed.

[0027] The third step is to vibrate the gradient tin foam from left to right, back and forth, up and down in a small range to form gaps around the tin wire skeleton in the foundry sand.

[0028] Step 4: In an argon environment, heat to 670°C in a muffle furnace to melt the aluminum into a liquid, and then quickly inject the liquid aluminum into the gaps around the original gradient tin foam skeleton. Cool to form a flexible aluminum-tin gradient porous metal with a porosity of 0.98 and a pore density gradient of 20PPI-60PPI. Such as figure 1 shown.

[0029] Through simulation cal...

Embodiment 2

[0031] The preparation process of this embodiment is as follows:

[0032] The first step is to pour foundry sand into gradient polystyrene foam to form a mold.

[0033] In the second step, in an argon atmosphere, heat to 350°C in a muffle furnace to melt lead into a liquid, and then inject the liquid lead into a gradient polystyrene foam mold. On cooling, the original gradient tin foam is formed.

[0034] The third step is to vibrate the gradient aluminum foam left, right, front, back, up and down in a small range to form gaps around the aluminum wire skeleton in the foundry sand.

[0035] Step 4: In an argon environment, heat up to 1100°C in a muffle furnace to melt copper into liquid, and then quickly inject liquid copper into the voids around the original gradient lead foam skeleton. Cool to form a flexible copper-lead gradient porous metal with a porosity of 0.98 and 20PPI-60PPI. Such as figure 2 shown.

[0036] Through simulation calculation, it is found that under ...

Images