A gas shielding method for titanium alloy electric arc additive manufacturing

Abstract

The application discloses a gas protection method for titanium alloy electric arc additive manufacturing, and comprises the following steps: step one, processing metal blocks; step two, placing a pair of metal blocks in parallel on both sides of a first layer of a titanium alloy wall structure region to be additively manufactured, to form a protection gas storage groove; step three, performing additive manufacturing of the first layer of the titanium alloy wall structure; step four, tightly placing the metal blocks in step two on the first layer of the titanium alloy wall structure, and placing a pair of new metal blocks on the metal blocks in step two, to form a protection gas storage groove which is synchronously increased with the additive height; step five, performing additive manufacturing of a second layer of the titanium alloy wall structure; and step six, performing additive manufacturing of the titanium alloy wall structure according to the method of steps four to five, until the height of the titanium alloy wall structure reaches the additive requirement. The method can be used for gas protection in the process of additive manufacturing of a titanium alloy wall structure component.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of electric arc additive manufacturing, and relates to a gas protection method for electric arc additive manufacturing of titanium alloy, in particular to a gas protection method for TIG electric arc additive manufacturing of wall titanium alloy. BACKGROUND

[0002] When a titanium alloy wall member is manufactured by using TIG electric arc additive manufacturing, in the process of layer-by-layer stacking, the low-layer titanium alloy that has been solidified is heated by the heat conduction of the upper molten pool, and high-temperature oxidation occurs on the side wall of the low-layer wall. Controlling the temperature between layers cannot prevent the heat conduction in the additive process, and the side wall of the wall will continue to be oxidized as the height of the additive manufactured member increases.

[0003] The common gas protection method for titanium alloy welding is to hang a gas protection cover behind the nozzle of a welding torch, and to install a gas supply pipeline on the cover. Independent gas supply is performed on the inside of the cover, which can effectively protect the titanium alloy welding process. However, for layer-by-layer additive manufacturing, the height of the wall structure gradually increases during the additive process, and the density of the protective gas such as argon used is greater than that of air. The protective gas sprayed from the cover cannot stay on the side wall of the wall structure and will sink to the base plate position, so the wall structure cannot be effectively protected. A closed argon tank can effectively protect the additive manufactured wall structure, but the argon tank structure is troublesome to install, and vacuumization and gas replacement need to be performed every time, which increases the additive manufacturing cost and is not conducive to the improvement of the additive manufacturing efficiency. SUMMARY

[0004] In order to solve the problem of side wall oxidation when the height of the TIG electric arc additive titanium alloy wall structure is greater than 30 mm, the application provides a gas protection method for electric arc additive manufacturing of titanium alloy.

[0005] The purpose of the application is achieved by the following technical scheme:

[0006] The application provides a gas protection method for electric arc additive manufacturing of titanium alloy, which comprises the following steps:

[0007] Step 1: processing a metal block with a thickness of 1-5 mm, a width of 10-50 mm, and a length equal to the length of the wall structure, wherein the material of the metal block is a high-melting-point metal material such as titanium alloy or stainless steel;

[0008] Step 2: placing a pair of metal blocks in parallel on both sides of the first layer of titanium alloy wall structure to be added, so that the horizontal distance between each metal block and the first layer of titanium alloy wall structure to be added is 1-5 mm, the height is 0-2 mm higher than the height of the first layer of titanium alloy wall structure to be added, and the metal block is located 5-10 mm below the protection gas nozzle of the welding torch to form a protection gas storage groove.

[0009] Step three, proceed with the first layer of titanium alloy wall structure additive work;

[0010] Step four, the metal block in step two is tightly attached to the first layer of titanium alloy wall structure, and a pair of new metal blocks is placed on the metal block in step two, so that the horizontal distance between the new metal block and the second layer of titanium alloy wall structure to be added is 1-5mm, and the total height of the metal block is higher than the height of the second layer of titanium alloy wall structure to be added by 0-2mm, forming a protective gas storage groove which is raised synchronously with the additive height;

[0011] Step five, proceed with the second layer of titanium alloy wall structure additive work;

[0012] Step six, proceed with the additive work of the titanium alloy wall structure according to the method of step four to step five until the height of the titanium alloy wall structure reaches the additive requirement.

[0013] Compared with the prior art, the present application has the following advantages:

[0014] 1. The method of the present application can be used for gas protection during the additive manufacturing of wall structure titanium alloy components. In the additive manufacturing process, metal blocks of appropriate size are used to provide in-situ gas protection for the additive manufacturing wall in a layer-by-layer stacking form.

[0015] 2. The method of the present application is simple to make and install, flexible to use, and can effectively protect the side wall of the additive manufacturing wall structure, reducing the oxidation of titanium alloy additive manufacturing components and ensuring quality. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is a gas protection work flowchart of the present application;

[0017] Figure 2 is a gas protection work schematic diagram of the present application;

[0018] Figure 3 is a comparison diagram of the protection effect of the side wall of the wall structure between the gas protection method of the present application and the conventional cover protection method. DETAILED DESCRIPTION

[0019] The technical solutions of the present application will be further described below in conjunction with the drawings, but are not limited thereto. Any modification or equivalent replacement to the technical solutions of the present application without departing from the spirit and scope of the present application shall be covered in the protection scope of the present application.

[0020] Example 1:

[0021] This example provides a gas protection method for titanium alloy electric arc additive manufacturing, as shown in Figure 1 and Figure 2As shown, the method comprises the following steps:

[0022] Step one, process the stainless steel metal block with thickness of 2mm, width of 10mm and length of 100mm.

[0023] Step two, place a pair of metal blocks in parallel on both sides of the first layer of the titanium alloy wall structure to be added, so that each metal block has a horizontal distance of 2mm from the first layer of the titanium alloy wall structure to be added, a height of 1mm higher than the height of the first layer of the titanium alloy wall structure to be added, and is located 10mm below the nozzle of the welding gun protection gas, thereby forming a protection gas storage tank.

[0024] Step three, perform the first layer of the titanium alloy wall addition work.

[0025] Step four, place the metal block in step two close to the first layer of the titanium alloy wall structure, and place a pair of new metal blocks on the metal blocks in step two, that is, when placing the second layer of the metal block, the first layer of the metal block is close to the first layer of the titanium alloy wall which has been added, and the new metal block has a horizontal distance of 2mm from the second layer of the titanium alloy wall structure to be added, and a height of 1mm higher than the height of the second layer of the titanium alloy wall structure to be added, thereby forming a protection gas storage tank which increases synchronously with the addition height.

[0026] Step five, perform the second layer of the titanium alloy wall addition work.

[0027] Step six, perform the addition work of the titanium alloy wall structure according to the method of step four to step five until the height of the titanium alloy wall structure reaches 100mm.

[0028] Figure 3 The figure shows the protection effect of the method of the application and the ordinary cover method on the wall structure of the titanium alloy additive manufacturing. From Figure 3 It can be seen that the wall structure side wall protection effect of the method of the application is good, the side wall is silver white without oxidation marks, and the ordinary cover method cannot effectively protect the side wall of the wall structure with gray color, part of the area is blue purple, and the oxidation marks are obvious.

[0029] Example 2:

[0030] The embodiment provides a gas protection method for titanium alloy electric arc additive manufacturing, and the method comprises the following steps:

[0031] Step one, process the titanium alloy metal block with thickness of 1mm, width of 5mm and length of 50mm.

[0032] Step two, place a pair of metal blocks in parallel on both sides of the first layer of the titanium alloy wall structure to be added, so that each metal block is 3mm apart from the first layer of the titanium alloy wall structure to be added horizontally, 2mm higher than the height of the first layer of the titanium alloy wall structure to be added, and 5mm below the nozzle of the welding gun protection gas, forming a protection gas storage tank.

[0033] Step three, add the first layer of titanium alloy wall;

[0034] Step four, place the metal blocks in step two closely against the first layer of titanium alloy wall structure, and place a pair of new metal blocks on the metal blocks in step two, that is, when placing the second layer of metal blocks, the first layer of metal blocks is closely attached to the first layer of titanium alloy wall which has been added, and the new metal blocks are 3mm apart from the second layer of titanium alloy wall structure to be added horizontally, 2mm higher than the height of the second layer of titanium alloy wall structure, forming a protection gas storage tank which increases synchronously with the height of the addition.

[0035] Step five, add the second layer of titanium alloy wall structure.

[0036] Step six, add the titanium alloy wall structure according to the method of step four to step five until the height of the titanium alloy wall structure reaches 50mm.

Claims

1. A gas protection method for titanium alloy arc additive manufacturing, characterized in that The method comprises the following steps: Step 1: Process a metal block with a thickness of 1 to 5 mm, a width of 10 to 50 mm, and a length equal to the length of the wall structure; Step 2: Place a pair of metal blocks in parallel on both sides of the first layer of titanium alloy wall structure to be added, so that the horizontal distance between each metal block and the first layer of titanium alloy wall structure to be added is 1 to 5 mm, forming a protective gas storage tank; Step 3: Add material to the first layer of titanium alloy wall structure; Step 4: Place the metal blocks from step 2 close to the first layer of titanium alloy wall structure, and place a pair of new metal blocks on top of the metal blocks from step 2, with a horizontal spacing of 1 to 5 mm between the new metal blocks and the second layer of titanium alloy wall structure to be added, forming a protective gas storage tank that increases synchronously with the height of the added material; Step 5: Add material to the second layer of titanium alloy wall structure; Step 6: Perform additive work on the titanium alloy wall structure according to the methods of steps 4 and 5 until the height of the titanium alloy wall structure meets the additive requirements.

2. The gas shielding method for titanium alloy arc additive manufacturing according to claim 1, characterized in that The material of the metal block is titanium alloy or stainless steel.

3. The gas shielding method for titanium alloy arc additive manufacturing according to claim 1, characterized in that In the step 2, the upper surface of the metal block is 5 to 10 mm below the shielding gas nozzle of the welding gun.

4. The gas shielding method for titanium alloy arc additive manufacturing according to claim 1, characterized in that In the step 2, the height of the metal block is 0 to 2 mm higher than the height of the first layer of titanium alloy wall structure.

5. The gas shielding method for titanium alloy arc additive manufacturing according to claim 1, characterized in that In the step 4, the total height of the metal block is 0 to 2 mm higher than the height of the second layer of titanium alloy wall structure to be added.

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