Array-spraying additive manufacturing apparatus and method for manufacturing large-sized equiaxed crystal aluminum alloy ingot

Patent metadata

Field	Value
Publication number	US-11524332-B2
Application number	US-201817288038-A
Country	US
Kind code	B2
Filing date	Dec 20, 2018
Priority date	Nov 16, 2018
Publication date	Dec 13, 2022
Grant date	Dec 13, 2022

Abstract

An array-spraying additive manufacturing apparatus and method for manufacturing a large-sized equiaxed crystal aluminum alloy ingot, comprising: a liquid aluminum spraying mechanism having array nozzles disposed in an atmospheric pressure chamber, a movable condensing mechanism disposed in the atmospheric pressure chamber below the liquid aluminum spraying mechanism, and a control mechanism. The control mechanism sends an upward guiding command to a release mechanism and issues a three-dimensional movement command to the movable condensing mechanism, such that liquid aluminum in the liquid aluminum spraying mechanism is sprayed at the surface of the movable condensing mechanism in a continuous array of liquid flows according to a preset path and is rapidly condensed to form an ingot. Also disclosed is an additive manufacturing method employing the apparatus.

First claim

What is claimed is:

1. An array-spraying additive manufacturing apparatus for a equiaxed crystal aluminum alloy ingot, comprising:
a liquid aluminum spraying mechanism having array nozzles and disposed in an atmospheric pressure chamber, and a movable condensing mechanism and a controller which are disposed in the atmospheric pressure chamber and below the liquid aluminum spraying mechanism, wherein the controller sends an upward guiding command to a release controller and issue a three-dimensional movement command to the movable condensing mechanism respectively, such that liquid aluminum in the liquid aluminum spraying mechanism is sprayed to a surface of the movable condensing mechanism in a form of a continuous array of liquid flows according to a preset path, and is rapidly condensed to form the ingot; and
the liquid aluminum spraying mechanism comprises: the release controller, a liquid aluminum chamber, and array nozzles, wherein the array nozzles are disposed at a bottom of the liquid aluminum chamber, and the release controller is connected with the controller to control a spraying speed of the liquid aluminum;
a nozzle row spacing and a nozzle column spacing of the array nozzles are less than 300 mm, and a nozzle aperture is 0.2 mm-30 mm; and a single-pass movement length of a single nozzle is equal to the nozzle column spacing, and a total width of movement of the single nozzle is equal to the nozzle row spacing;
the movable condensing mechanism comprises: a condensing table disposed right facing the array nozzles, a two-dimensional movement controller, the two-dimensional movement controller being vertically movable and disposed under the condensing table, and a downward movement controller, wherein the two-dimensional movement controller and the downward movement controller are respectively connected to the controller, and receive two-dimensional movement command and vertical movement command so as to realize three-dimensional movement and combined control is adopted for geometric arrangement of the array nozzles, cooling capacity of the condensing mechanism and a two-dimensional movement path, to make the liquid aluminum spread and be continuously kept in a semisolid state at a printing interface, thereby achieving metallurgical combination of a printing area corresponding to each nozzle.

2. The apparatus according to claim 1 , wherein the atmospheric pressure chamber is provided with a vacuum pump connected to the controller, such that internal air pressure is further adjusted through the vacuum pump; and the atmospheric pressure chamber is connected with an inert gas source to provide inert gas protection for inside of the atmospheric pressure chamber.

3. The apparatus according to claim 1 , wherein the release controller comprises an upward movement controller and a plug pole, wherein the plug pole is matched with the array nozzles, and the upward movement controller is respectively connected with the plug pole and the controller, thereby receiving a release command and controlling the plug pole to lift upward to release the array nozzles.

4. The apparatus according to claim 1 , wherein in-chamber heaters which are connected with the controller are further disposed inside the liquid aluminum chamber.

5. The apparatus according to claim 1 , wherein nozzle heaters are further disposed outside of the array nozzles.

6. The apparatus according to claim 1 , wherein a cooling liquid flow channel is disposed inside the condensing table.

7. The apparatus according to claim 1 , wherein the controller comprises: a movement controller and a general controller, wherein the movement controller is connected to the general controller and transmits movement information of the movable condensing mechanism, and the general controller is connected with the release controller and the vacuum pump respectively and transmits information of movement of the release controller and information of opening and closing of the vacuum pump, is connected with the two-dimensional movement controller and configured to transmit movement information of the two-dimensional movement controller, is connected with the downward movement controller and transmit movement information of the downward movement controller.

8. An array-spraying additive manufacturing method for manufacturing a equiaxed crystal aluminum alloy ingot based on the apparatus according to claim 1 , comprising following steps:
Step 1: placing a plug pole in a lowest position to make the nozzles in a closed state; turning on in-chamber heaters for performing preheating to reach a liquid aluminum temperature and keeping the temperature; opening an inlet gate to allow the liquid aluminum to flow into the liquid aluminum chamber, and closing the inlet gate after the liquid aluminum is controlled by a liquid level meter to reach a preset height, turning on nozzle heaters to preheat the nozzles, sealing an airtight condensing chamber, and turning on the vacuum pump to vacuum the airtight condensing chamber; and turning off the vacuum pump when a vacuum degree meets a requirement, and introducing inert gas from an inert gas source to reach a preset pressure;
Step 2: turning on cooling water, controlling the downward movement controller by a movement controller, the movement controller connected to the general controller and transmitting movement information of the movable condensing mechanism, so as to make a distance between the nozzles and the condensing table reach a preset distance, then turning on a two-dimensional movement controller to enable the nozzles to move relative to the condensing table periodically and repeatedly; turning on an upward movement controller to lift upward the plug pole, so as to make the liquid aluminum enter the nozzles, the upward movement controller connected with the plug pole and the controller; turning on the vacuum pump to perform pumping to make a pressure of an airtight condensing chamber less than 1 atm, wherein the liquid aluminum in the liquid aluminum chamber above the airtight condensing chamber is sprayed out as stable liquid columns through the nozzles under above-mentioned negative pressure generated inside the airtight condensing chamber, and sprayed onto the condensing table to form the ingot; and controlling, after ingot preparation starts, the downward movement controller to move the condensing table downward, wherein during the ingot preparation process, with continuous consumption of the liquid aluminum, when a liquid level in the liquid aluminum chamber drops to a warning level, the inlet gate is opened to replenish the liquid aluminum until reaching a stable level, and then the inlet gate is closed; and
Step 3: turning off, upon preparation of the ingots is completed, the plug pole to block flowing of the liquid aluminum out from the nozzles, turning off the two-dimensional movement controller and the downward movement controller, turning off a heating power supply, and turning off the cooling water after the ingot is cooled, thus finishing the preparation process.

Assignees

• Univ Shanghai Jiaotong

Inventors

• Zhang Jiao
• Sun Baode
• Dong Qing

Classifications

• C23C4/123

  Spraying molten metal · CPC title

• B22D23/003

  Moulding by spraying metal on a surface · CPC title

• B33Y30/00

  Apparatus for additive manufacturing; Details thereof or accessories therefor · CPC title

• B33Y10/00

  Processes of additive manufacturing · CPC title

• B22F3/115 Primary

  by spraying molten metal, i.e. spray sintering, spray casting · CPC title