CN113070491B - Forming method for 3D printing of high-temperature alloy bionic structure - Google Patents

Abstract

The invention relates to the technical field of 3D printing, and provides a forming method for 3D printing of a high-temperature alloy bionic structure, aiming at solving the problem that the existing 3D printing technology cannot realize the manufacturing of a high-efficiency heat dissipation self-growing heat dissipation structure of an aerospace engine core component, and the forming method for 3D printing of the high-temperature alloy bionic structure comprises the following steps: s1, determining the placing angle of the 3D printed part, and performing simulation according to the determined placing angle; s2, determining a support adding part; s3, adding a support structure at the support adding part to form a printing model; s4, slicing and subdividing by using the forming parameters, forming a printing program and importing the printing program into a 3D printer; and S5, starting the 3D printer, and spreading powder for printing. The invention is especially suitable for the integrated manufacture of the high-efficiency heat-dissipation self-growing heat dissipation structure, and has higher social use value and application prospect.

Description

A forming method for 3D printing of superalloy biomimetic structures

technical field

The invention relates to the technical field of 3D printing, in particular to a forming method for 3D printing of a biomimetic structure of a superalloy.

Background technique

SLM (selective laser melting) is a main technical approach in the additive manufacturing of metal materials. This technology uses laser as the energy source, scans the metal superalloy powder layer by layer according to the path planned in the 3D CAD slice model, and the scanned metal superalloy powder is melted and solidified to achieve the effect of metallurgical bonding, and finally obtain Metal parts for which the model is designed.

The core components of aerospace engines all serve under high temperature conditions, and the heat dissipation design of the components is particularly important. A self-growing heat dissipation structure with high efficiency has been designed, which can fit the heat transfer path and conduct heat conduction effectively, but the structure is complex. Special, fine size, local features are only 0.1mm, conventional manufacturing is difficult and the cycle is long, and 3D printing is undoubtedly the most suitable manufacturing method for complex structure forming.

However, the existing 3D printing technology cannot realize the refined manufacturing of the structure, and can only change the structural design, reduce the heat dissipation efficiency and R&D indicators to meet the existing 3D printing technology. To this end, we propose a forming method for 3D printing of superalloy biomimetic structures.

SUMMARY OF THE INVENTION

(1) Technical problems solved

In view of the deficiencies of the prior art, the present invention provides a forming method for 3D printing of a biomimetic structure of a superalloy, which overcomes the deficiencies of the prior art, has a reasonable design and a compact structure, and aims to solve the problem that the existing 3D printing technology cannot be realized. High-efficiency heat dissipation of aerospace engine core components is the problem of self-growing heat dissipation structure manufacturing.

(2) Technical solutions

To achieve the above purpose, the present invention is achieved through the following technical solutions:

A forming method for 3D printing of a biomimetic structure of a superalloy, the forming method comprises the following steps:

S1. Determine the placement angle of the 3D printed parts, and use the simulation software to simulate according to the determined placement angle;

S2. Determine the support addition position according to the simulation results. The judgment basis of the support addition position is shown in formula <1>, and if formula <1> is satisfied, it is determined that the position needs support addition;

<1>

<1>

-Mises等效应力；R -3D打印过程中，该温度下的材料三点弯强度；where:

-Mises equivalent stress; R-3D printing process, the three-point bending strength of the material at this temperature;

S3. Add support structure at the support adding part to form a printing model;

S4. Use the forming parameters for slicing and subdivision to form a printing program and import it into the 3D printer;

S5. The 3D printer is loaded with superalloy powder, installed with a flexible scraper, and then started, and the printer spreads powder for printing.

Preferably, in the step S4, the thickness of the formed slice is 0.015-0.03 mm.

Preferably, in the step S5, the particle size of the raw material of the superalloy powder is 10-55 μm.

Preferably, in the step S5, the material of the flexible scraper is a wear-resistant plastic material.

The present invention also provides a support form for 3D printing of a high temperature alloy biomimetic structure, wherein the 3D printing support form is that a hollow rod-shaped support structure is used at the support addition part.

Preferably, the outer diameter Φ of the hollow rod-shaped support structure is 0.6mm~0.8mm, and the wall thickness is 0.08mm~0.11mm.

Preferably, the support adding part is a stress concentration area obtained by using simulation software to simulate.

The invention also provides a printing parameter for a 3D printing forming method of a bionic structure of a superalloy, wherein the printing parameter includes a printing parameter of a support structure and a printing parameter of a part body;

Support structure printing parameter indicators include: laser power, laser scanning speed, laser path, scanning strategy, scanning track spacing, and spot diameter;

Part body printing parameters include: inner filling laser power, inner filling laser scanning speed, track spacing, number of outer circles, scanning path, outer circle laser power, outer circle scanning speed, and spot diameter.

Preferably, in the printing parameters of the support structure, the laser power is 80-120W, the laser scanning speed is 850-1100mm/s, the laser path is spiral, the scanning strategy is one cycle for every three layers scanned, and the middle layer is designed not to scan during the cycle , Front and back layer scanning, the laser scanning track spacing is 0.04~0.06mm, and the spot diameter is 0.6~0.75mm.

Preferably, in the printing parameters of the part body, the inner filling laser power is 130~160W, the inner filling laser scanning speed is 950~1200mm/s, the track spacing is 0.1mm~0.13mm, the spot diameter is 0.6~0.75mm, and the outer filling laser is 0.6~0.75mm. The number of circles is 2 circles;

The laser power of the outer ring of the first layer is 80~105W, and the laser scanning speed is 290~350mm/s;

The laser power of the outer ring of the second layer is 70~85W, and the laser scanning speed of the outer ring is 900~1150mm/s.

(3) Beneficial effects

The embodiment of the present invention provides a forming method for 3D printing of a biomimetic structure of a superalloy, which has the following beneficial effects:

1. The present invention adopts a hollow rod-shaped support structure suitable for 3D printing, which has lower strength than the existing solid conical support, and is easier to remove without damaging the parts. At the same time, since the interior of the support structure is hollow, the support weight is reduced, and the consumption of printing raw materials is reduced. also significantly reduced.

2. The present invention obtains the stress concentration area by simulating the forming process, reduces the support addition parts to the greatest extent, and improves the forming stability.

3. The special 3D printing laser forming and sintering parameters adopted in the present invention enable the refined bionic structure to be manufactured by 3D printing technology.

Description of drawings

In the following, the preferred embodiments will be described in a clear and easy-to-understand manner with reference to the accompanying drawings, and the above-mentioned characteristics, technical characteristics, advantages and implementation methods of a support form, printing parameters and forming method for 3D printing of a superalloy biomimetic structure will be given. Further explanation.

1 is a flowchart of a forming method for 3D printing of a bionic structure of a superalloy in the present invention;

2 is a schematic diagram of a hollow rod-shaped support structure of the present invention;

Fig. 3 is the part diagram of bionic structure in the present invention;

4 is a bottom view of a three-dimensional simulation of a bionic structure in the present invention;

FIG. 5 is an added diagram of the bionic structure support in the present invention.

Detailed ways

Below in conjunction with accompanying drawing 1-5 and embodiment, the present invention is further described:

Example 1

A forming method for 3D printing of biomimetic structure of superalloy, with reference to accompanying drawings 3-5, the forming method includes the following steps:

S1. Select the placement form with the bottom facing down and the bionic structure facing up, and use the simulation software to simulate according to the determined placement angle;

S2. Determine the support addition position according to the simulation results. The judgment basis of the support addition position is shown in formula <1>, and if formula <1> is satisfied, it is determined that the position needs support addition;

<1>

<1>

-Mises等效应力；R -3D打印过程中，该温度下的材料三点弯强度；where:

-Mises equivalent stress; R-3D printing process, the three-point bending strength of the material at this temperature;

S3, adding a hollow rod-shaped support structure at the support adding part to form a printing model;

S4. Use the forming parameters for slicing and subdivision to form a printing program and import it into the 3D printer;

S5. The 3D printer is loaded with superalloy powder, installed with a flexible scraper, and then started, and the printer spreads powder for printing;

Wherein, referring to the three-dimensional simulation diagram of the bionic structure of the accompanying drawing 3, the characteristic size is 0.1 mm, referring to the accompanying drawings 4 and 5, the accompanying drawing 4 is the support addition part determined according to the simulation result after the simulation software is used for the simulation (the light gray display part ), and Figure 5 adds a three-dimensional diagram for the selected hollow rod-shaped support structure for support.

In this embodiment, in the step S4, the thickness of the formed slice is 0.015-0.03 mm.

In this embodiment, in the step S5, the particle size of the raw material of the superalloy powder is 10-55 μm.

In this embodiment, in the step S5, the material of the flexible scraper is a wear-resistant plastic material.

Example 2

The present invention also provides a support form for 3D printing of a biomimetic structure of a superalloy. The 3D printing support form is that a hollow rod-shaped support structure is used in the support addition part. As shown in FIG. 2 , the hollow rod-shaped support structure has a cone at one end. A cylindrical structure with a hollow interior.

In this embodiment, as shown in FIG. 2 , the outer diameter Φ of the hollow rod-shaped support structure is 0.6 mm~0.8 mm, and the wall thickness is 0.08 mm~0.11 mm.

In this embodiment, as shown in FIGS. 3 and 4 , the support adding portion is a stress concentration area obtained by simulation using simulation software.

For other undescribed structures, refer to Embodiment 1.

Example 3

The invention also provides a printing parameter for a 3D printing forming method of a bionic structure of a superalloy, wherein the printing parameter includes a printing parameter of a support structure and a printing parameter of a part body;

Support structure printing parameter indicators include: laser power, laser scanning speed, laser path, scanning strategy, scanning track spacing, and spot diameter;

Part body printing parameters include: inner filling laser power, inner filling laser scanning speed, track spacing, number of outer circles, scanning path, outer circle laser power, outer circle scanning speed, and spot diameter.

In this embodiment, in the printing parameters of the support structure, the laser power is 80-120W, the laser scanning speed is 850-1100mm/s, the laser path is spiral, the scanning strategy is one cycle for every three layers scanned, and the middle layer is designed in the cycle No scanning, front and back layer scanning, the laser scanning track spacing is 0.04~0.06mm, and the spot diameter is 0.6~0.75mm.

In this embodiment, in the printing parameters of the part body, the inner filling laser power is 130~160W, the inner filling laser scanning speed is 950~1200mm/s, the track spacing is 0.1mm~0.13mm, and the spot diameter is 0.6~0.75mm , the number of outer rings is 2;

The laser power of the outer ring of the first layer is 80~105W, and the laser scanning speed is 290~350mm/s;

The laser power of the outer ring of the second layer is 70~85W, and the laser scanning speed of the outer ring is 900~1150mm/s.

For other undescribed structures, refer to Embodiments 1 and 2.

According to the support form, printing parameters and forming method for 3D printing of the biomimetic structure of the superalloy according to the above embodiments of the present invention, a hollow rod-shaped support structure suitable for 3D printing is adopted, which has lower strength than the existing solid conical support, and is easier to remove without At the same time, due to the hollow interior design of the support structure, the support weight is reduced, and the consumption of printing raw materials is also greatly reduced;

The existing 3D printing technology requires that the bottom of the structure with a forming angle of less than 45° needs to be supported. However, due to the complexity and particularity of the bionic heat dissipation structure, if a support is added at the bottom of the area where the forming angle is less than 45°, the support volume will be large and refined. The structure will fail to form; this method obtains the stress concentration area through the simulation of the forming process, minimizes the addition of support parts, and improves the forming stability;

Combined with the special 3D printing laser forming and sintering parameters of the present invention, the refined bionic structure can be manufactured by 3D printing technology, which provides strong support for the development of engines in the aerospace field.

The embodiment of the present invention announces the preferred embodiment, but is not limited to this, those of ordinary skill in the art can easily understand the spirit of the present invention according to the above-mentioned embodiment, and make different extensions and changes, However, as long as they do not depart from the spirit of the present invention, they are all within the protection scope of the present invention.

Claims (6)

1. A forming method for 3D printing of a high-temperature alloy bionic structure is characterized by comprising the following steps:

s1, determining the placing angle of the 3D printed part, and performing simulation by using simulation software according to the determined placing angle;

s2, determining a support adding part according to the simulation result, wherein the judgment of the support adding part is determined as that the part needs to be supported and added when the formula <1> is satisfied according to the judgment of the support adding part shown as the formula <1 >;

<1>

in the formula:

-Mises equivalent stress; in the R-3D printing process, the three-point bending strength of the material at the temperature is obtained;

s3, adding a support structure at the support adding part to form a printing model;

s4, slicing and subdividing by using the forming parameters, forming a printing program and importing the printing program into a 3D printer;

s5, the 3D printer is started after high-temperature alloy powder is filled and the flexible scraper is installed, and the printer spreads the powder for printing;

the 3D printing support mode is that a hollow rod-shaped support structure is used at the support adding position;

the printing parameters for the 3D printing forming method of the high-temperature alloy bionic structure comprise the printing parameters of a supporting structure and the printing parameters of a part body:

in the printing parameters of the supporting structure, the laser power is 80-120W, the laser scanning speed is 850-1100 mm/s, the laser path is spiral, the scanning strategy is one period of three layers of scanning, the middle layer is not scanned, the front layer and the rear layer are scanned in the period, and the distance between laser scanning tracks is 0.04-0.06 mm;

in the printing parameters of the part body, the power of filling laser is 130-160W, the scanning speed of the filling laser is 950-1200 mm/s, the track spacing is 0.1-0.13 mm, the diameter of a light spot is 0.6-0.75 mm, and the number of outer rings is 2;

the laser power of the outer ring of the first layer is 80-105W, and the laser scanning speed is 290-350 mm/s;

the laser power of the second outer ring is 70-85W, and the laser scanning speed of the outer ring is 900-1150 mm/s.

2. The forming method for 3D printing of the superalloy biomimetic structure as in claim 1, wherein: in the step S4, the thickness of the formed slice is 0.015 to 0.03 mm.

3. The forming method for 3D printing of the superalloy biomimetic structure as in claim 1, wherein: in the step S5, the particle size of the high-temperature alloy powder raw material is 10-55 μm.

4. The forming method for 3D printing of the superalloy biomimetic structure as in claim 1, wherein: in step S5, the flexible scraper is made of a wear-resistant plastic material.

5. The forming method for 3D printing of the superalloy biomimetic structure as in claim 1, wherein: the outer diameter phi of the hollow rod-shaped supporting structure is 0.6 mm-0.8 mm, and the wall thickness is 0.08 mm-0.11 mm.

6. The forming method for 3D printing of the superalloy biomimetic structure as in claim 1, wherein: the support adding part is a stress concentration area obtained by simulation with simulation software.

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