CN110052695B - A kind of diffusion welding method for developing internal flow channel of aluminum alloy liquid cooling component - Google Patents

Abstract

The invention relates to a diffusion welding method for developing an internal flow channel of an aluminum alloy liquid cooling component. The aluminum alloy liquid cooling assembly includes an aluminum alloy shell and a cover plate. The specific operation steps are as follows: 1. On the diffusion welding workbench, assemble the cleaned aluminum alloy shell and cover plate; 2. On the outer surface of the cover plate Cover with graphite paper; 3. Send the aluminum alloy liquid-cooled assembly covered with graphite paper into the vacuum chamber of the diffusion welding equipment, and vacuumize for diffusion welding; 4. After the welding is completed, remove the graphite paper and it can be placed on the outside of the cover plate The surface shows the internal runner locations, where the white areas are runners and the black areas are non-runners. The invention utilizes the diffusion principle of the carbon element in the graphite paper to the aluminum alloy cover plate, and displays the positions of the flow channel and the non-flow channel on the outer surface of the cover plate; the implementation process is carried out synchronously with the diffusion welding process, except that the laying of the graphite paper is increased. Compared with conventional ultrasonic imaging or X-ray imaging, the operation is simple, the efficiency is high, and the cost is low.

Description

A kind of diffusion welding method for developing internal flow channel of aluminum alloy liquid cooling component

technical field

The invention belongs to the technical field of material welding, and in particular relates to a diffusion welding method for developing an internal flow channel of an aluminum alloy liquid cooling component.

Background technique

The aluminum alloy liquid cooling component is one of the core structures of the radar system, which plays a role in dissipating heat for the radar electronic components and ensuring the reliable operation of the radar system. Due to the requirement of light weight, the internal flow channel of the aluminum alloy liquid cooling component is compact, and the width of the solid part between the water channels is small. At the same time, high-density blind-plug mounting holes are generally designed on the aluminum alloy liquid cooling components, which are located on the solid part between the water channels. Therefore, the distance between the blind jack and the water channel wall is very limited. Therefore, it is one of the key issues that must be controlled for aluminum alloy liquid cooling components to ensure that the blind jack will not cause the water channel to break.

One of the common manufacturing methods of aluminum alloy liquid cooling components is diffusion welding, which is to integrally weld the shell and cover plate with the processed flow channel. Due to the large pressure required in the diffusion welding process, the liquid-cooled components will deform to a certain extent after welding, especially for larger-sized liquid-cooled components, the deformation is generally large. In order to ensure that the blind socket processing does not break the wall, it is generally necessary to display the position of the runner after welding to provide a basis for subsequent processing. The commonly used display method is ultrasonic method or X-ray method. Both methods are separate processes, require special equipment, and show high cost and long cycle, which seriously affect the production process of products. Therefore, a convenient and efficient method is urgently needed to solve the display of the internal flow channel position of the diffusion solder liquid cooling component to meet the production requirements of the product.

SUMMARY OF THE INVENTION

In order to conveniently display the internal flow channel of the aluminum alloy liquid cooling component and provide a position basis for subsequent processing, the present invention provides a diffusion welding method for developing the internal flow channel of the aluminum alloy liquid cooling component.

A diffusion welding method for developing an internal flow channel of an aluminum alloy liquid cooling assembly, wherein the aluminum alloy liquid cooling assembly includes an aluminum alloy casing and a cover plate, and the aluminum alloy casing is provided with a liquid inlet, a flow channel and a liquid outlet, Between adjacent runners is the runner wall; the specific operation steps are as follows:

(1) On the diffusion welding workbench, complete the assembly of the cleaned aluminum alloy shell and cover;

(2) The outer surface of the cover plate is covered with graphite paper; the thickness of the graphite paper is 30-100um;

(3) The aluminum alloy liquid-cooled components covered with graphite paper are sent into the vacuum chamber of the diffusion welding equipment, and vacuumed for diffusion welding; diffusion welding process conditions: the heating rate is 10-20℃/min, and the welding temperature is 550 ℃-580℃, the holding pressure at welding temperature is 4MPa-7MPa, and the time is 30-60min;

(4) After the welding is completed, remove the graphite paper to display the position of the internal flow channel on the outer surface of the cover plate, where the white area is the flow channel, and the black area is the non-flow channel.

Further limited technical solutions are as follows:

In step (1), the thickness of the cover plate is less than 8mm, so that the pressure on the contact surface between the graphite paper and the cover plate is uneven, and the pressure at the corresponding flow channel position is smaller than the corresponding Compression force at non-runner locations.

In step (2), if the graphite paper on the outer surface of the cover plate is a spliced graphite paper, the splicing gap between adjacent graphite papers is less than 0.5 mm.

In step (3), in the vacuum chamber of the diffusion welding equipment, the pressure head of the diffusion welding equipment is pre-pressed on the cover plate covered with the graphite paper to prevent the graphite paper from sliding.

The beneficial technical effect of the present invention is embodied in the following aspects:

1. The present invention utilizes the diffusion principle of carbon in the graphite paper to the aluminum alloy cover plate, and simultaneously utilizes the influence of the difference in force between the area of the cover plate corresponding to the flow channel and the corresponding non-flow channel area on the carbon diffusion effect, The positions of the runners and non-runners are shown on the outer surface of the cover. The outer surface of the cover plate shows the positions of the runners and the non-runners. During the implementation process, the process is synchronized with the diffusion welding process, but the process of laying graphite paper is added. Compared with conventional ultrasound imaging or X-ray imaging, the operation is simple, efficient and low-cost.

2. There are three reasons for using graphite paper as a diffusion medium: (1) At the temperature of diffusion welding, carbon and aluminum do not react chemically, and no new phase is formed, which has no effect on the phase of the cover plate; (2) The mutual diffusion solubility of carbon and aluminum is extremely small, the diffusion rate is low, and the display effect is close to the micron thickness level of the surface of the cover plate, which can be ignored, so it has no effect on the composition of the aluminum alloy cover plate; (3) Graphite paper is a flexible medium , During the heating process, there will be sliding between the aluminum alloy cover plate and the graphite paper, and the parts will not be scratched during the sliding process. At the same time, the flexible medium does not affect the force transmission of the cover plate, ensuring that the force on the welding surface is uniform and does not affect the welding effect.

3. Compared with conventional diffusion welding, in the process parameters of diffusion welding of the present invention, the welding temperature is 550°C-580°C, which is higher than that of conventional diffusion welding, thereby increasing the diffusion rate of carbon in the graphite paper to the surface of the aluminum alloy and improving the flow rate. channel display effect. The holding pressure is 4MPa-7MPa, which is higher than the conventional diffusion welding pressure. At the same time, the high pressure ensures that the graphite paper is closely attached to the cover plate, which improves the effect of aluminum alloy diffusion welding.

4. Graphite is black, aluminum alloy is nearly white, and the runner display effect is obvious.

Description of drawings

Figure 1 is an exploded view of the aluminum alloy liquid cooling assembly of the welded part.

FIG. 2 is a top view of an aluminum alloy housing with a runner.

FIG. 3 is a side view of the aluminum alloy liquid cooling assembly.

FIG. 4 is a schematic diagram showing the state of the flow channel on the outer surface of the cover plate after diffusion welding.

Serial number in the figure: aluminum alloy shell 1, liquid inlet 2, flow channel 3, flow channel wall 4, liquid outlet 5, cover plate 6, display flow channel 7, display flow channel wall 8, graphite paper 9.

Detailed ways

Below in conjunction with the accompanying drawings, the present invention will be further described through embodiments.

Example 1

Referring to FIGS. 1 and 2 , the aluminum alloy liquid cooling assembly to be diffusion welded includes an aluminum alloy casing 1 and a cover plate 6 . The aluminum alloy shell 1 is provided with a liquid inlet 2, a flow channel 3 and a liquid outlet 5, and between the adjacent flow channels 3 is a flow channel wall 4; The force difference between the area corresponding to the flow channel and the corresponding non-flow channel area on the outer surface of the cover plate.

The diffusion welding operation steps for developing the internal flow channel of the aluminum alloy liquid cooling component are as follows:

(1) On the diffusion welding workbench, complete the assembly of the cleaned aluminum alloy shell 1 and the cover plate 6.

(2) Referring to FIG. 3 , lay the cut graphite paper 9 on the outer surface of the cover plate 6 to ensure that the entire outer surface of the cover plate 6 is covered, and the thickness of the graphite paper is 60um; The splicing gap is less than 0.5mm.

(3) Press the pressure head of the diffusion welding equipment on the cover plate covered with graphite paper in advance to prevent the graphite paper from sliding; send the aluminum alloy liquid-cooled assembly covered with graphite paper into the vacuum chamber of the diffusion welding equipment, and close the diffusion welding The vacuum chamber of the equipment is evacuated, and diffusion welding is performed. The diffusion welding process conditions: the heating rate is 15°C/min, the welding temperature is 570°C, the holding pressure at the welding temperature is 6MPa, and the time is 30-60min.

(4) After the welding is completed, remove the graphite paper 9, and display the internal flow channel position on the outer surface of the cover plate 6, wherein the white area is the display flow channel 7, that is, the flow channel position; the black area is the display flow channel wall 8, that is, the non- Runner location, see Figure 4.

Claims (4)

1. A diffusion welding method for developing an internal runner of an aluminum alloy liquid cooling assembly comprises an aluminum alloy shell and a cover plate, wherein the aluminum alloy shell is provided with a liquid inlet, runners and a liquid outlet, and runner walls are arranged between adjacent runners; the method is characterized by comprising the following diffusion welding operation steps:

(1) on the diffusion welding workbench, the assembly of the cleaned aluminum alloy shell and the cover plate is completed;

(2) graphite paper is fully paved on the outer surface of the cover plate; the thickness of the graphite paper is 30-100 um;

(3) sending the aluminum alloy liquid cooling assembly paved with the graphite paper into a vacuum chamber of diffusion welding equipment, vacuumizing and performing diffusion welding; diffusion welding process conditions: the heating rate is 10-20 ℃/min, the welding temperature is 550-580 ℃, the pressure maintaining pressure is 4-7 MPa at the welding temperature, and the time is 30-60 min;

(4) after welding is finished, the position of the internal flow channel can be displayed on the outer surface of the cover plate by removing the graphite paper, wherein the white area is a flow channel, and the black area is a non-flow channel.

2. The method of claim 1, wherein the diffusion welding for internal channel development of the aluminum alloy liquid cooling assembly comprises: in the step (1), the thickness of the cover plate is less than 8 mm.

3. The method of claim 1, wherein the diffusion welding for internal channel development of the aluminum alloy liquid cooling assembly comprises: in the step (2), if the graphite paper on the outer surface of the cover plate is spliced graphite paper, the splicing gap between adjacent graphite papers is less than 0.5 mm.

4. The method of claim 1, wherein the diffusion welding for internal channel development of the aluminum alloy liquid cooling assembly comprises: in the step (3), in a vacuum chamber of the diffusion welding equipment, a pressure head of the diffusion welding equipment is pressed on a cover plate paved with graphite paper in advance to prevent the graphite paper from sliding.

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