CN110257751A - Method for realizing connection of copper-based alloy and die steel alloy by adopting 3D printing method - Google Patents

Abstract

A method for realizing the connection between a copper-based alloy and a die steel alloy by using a 3D printing method belongs to the technical field of 3D printing. The method firstly processes the qualified copper-based alloy base to be connected by traditional techniques such as casting and machining; uses the plasma spraying method to spray a layer of pure nickel on the to-be-printed surface of the copper-based alloy base, and performs sintering and grinding treatment , to make the surface of the base to be printed flat; then 3D printing is carried out on the treated base by 3D technology, and the printing material is mold steel alloy powder; finished product. This method can combine the good thermal conductivity of the copper-based alloy with the good mechanical properties of the die steel alloy, effectively improve the production efficiency and service life of the conformal cooling die, and has important social and economic benefits.

Description

A method for realizing the connection between copper-based alloy and die steel alloy by 3D printing method

technical field

The invention belongs to the technical field of 3D printing, and in particular relates to a method for realizing the connection between a copper-based alloy and a die steel alloy by using a 3D printing method.

Background technique

The cooling system of the injection mold affects the quality and production efficiency of the molded product. The traditional cooling system is difficult to achieve uniform cooling of the mold, and the molded product is prone to defects such as warpage and uneven shrinkage. The cooling water path of the accompanying cooling mold is changed according to the shape of the product, which can achieve uniform cooling of all parts of the product, significantly improve the quality of the product, reduce the cooling time, and has strong practicability, but the traditional processing method is not suitable for processing the accompanying cooling water path . As a kind of additive manufacturing, selective laser melting (SLM) has a high degree of freedom of forming, and the prepared metal parts have high density, high strength, low surface roughness, and can reduce the initial investment capital and save the manufacturing time, which is the most suitable for injection molds. Manufacturing brought revolutionary developments.

Copper-based alloys have good mechanical properties, high heat transfer, and non-magnetic properties. They are usually used to manufacture cavities and cores in injection molds and plastic magnet molds. They are widely used in the mold industry, but because of the 3D printing technology of copper-based alloys It is not yet mature and the mechanical properties of copper-based alloys cannot meet the actual production requirements, and it is currently impossible to use this alloy to manufacture conformal cooling molds. As a kind of maraging steel, MS1 die steel alloy has the characteristics of high strength, good toughness, good welding performance and good cold and hot working performance. It is a maraging steel powder specially used for 3D printing. In the research of , the selective laser melting method is used to form maraging steel to make conformal cooling injection mold, which has become the main application method of selective laser melting maraging steel. But MS1 die steel alloy has the problem of high cost.

SUMMARY OF THE INVENTION

The purpose of the present invention is to solve the problem that the random cooling mold cannot be well manufactured by using the copper-based alloy at present and the cost of manufacturing the random cooling mold by using the MS1 die steel alloy is relatively high, and provide a 3D printing method to realize the copper-based alloy. A method for connecting with die steel alloy, the method can realize seamless connection and the connection interface has good mechanical properties, and the manufactured conformal cooling die can be used for actual production.

To achieve the above object, the technical scheme adopted by the present invention is as follows:

A method for connecting a copper-based alloy and a die steel alloy by a 3D printing method, the method steps are as follows:

Step 1: Make a copper-based alloy base according to actual needs. It is necessary to ensure that the surfaces on the base that will be connected to the die steel are on the same plane, and thermal spraying technology is used on the surface of the base that will be connected to the die steel. A layer of nickel is plated; the copper-based alloy base can be processed by traditional machining or casting technology;

Step 2: sintering the nickel-plated surface;

Step 3: Use 3D printing technology to print printed parts with different shapes on the base according to actual needs;

Step 4: Heat treatment of the produced parts.

The beneficial effects of the present invention relative to the prior art are as follows: the present invention can obtain a conformal cooling die formed by connecting the copper-based alloy and the MS1 die steel alloy, and the high heat transfer properties of the copper-based alloy and the good MS1 die steel alloy can be obtained. Combined with the mechanical properties, the production efficiency and service life of the conformal cooling mold are well improved, which has high social and economic benefits, and is of great significance for the preparation of new high-end molds.

Description of drawings

Fig. 1 is the electron microscope picture of the copper-based alloy of embodiment 1 and MS1 die steel connection interface;

Fig. 2 is the electron microscope image at the connection interface of the copper-based alloy of embodiment 2 and MS1 die steel;

Fig. 3 is the electron microscope picture of the copper-based alloy of embodiment 3 and MS1 die steel connection interface;

FIG. 4 is an electron microscope image of the connection interface between the copper-based alloy of Example 4 and the MS1 die steel.

Detailed ways

The technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and embodiments, but are not limited thereto. Any modification or equivalent replacement of the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention shall cover within the scope of the present invention.

The present invention adopts the 3D printing technology to form the MS1 mold steel to make the part of the conformal cooling injection mold that is difficult to be manufactured by traditional processing, and uses the traditional processing technology to process the part with a simple cooling water path of the conformal cooling mold with the copper-based alloy as the base, and To realize the seamless connection of the two under the premise of ensuring the performance, the combination of the good mechanical properties of the MS1 die steel alloy and the high heat transfer performance of the copper-based alloy will greatly improve the production efficiency and service life of the conformal cooling die. , bringing considerable social and economic benefits.

Embodiment 1: This embodiment describes a method for realizing the connection between copper-based alloys and die steel alloys by using a 3D printing method. The method steps are as follows:

Step 1: Make a copper-based alloy base according to actual needs. It is necessary to ensure that the surfaces on the base that will be connected to the die steel are on the same plane, and thermal spraying technology is used on the surface of the base that will be connected to the die steel. A layer of nickel is plated; the copper-based alloy base can be processed by traditional machining or casting technology;

Step 2: Use the EOS M280 3D printer to sinter the nickel-plated surface, and grind the sintered nickel-plated surface into a flat surface;

Step 3: Use 3D printing technology to print printed parts with different shapes on the base according to actual needs;

Step 4: Heat treatment of the produced parts.

Embodiment 2: In Embodiment 1, a method for realizing the connection between a copper-based alloy and a die steel alloy using a 3D printing method, in step 1, the thickness of the nickel-plated layer is 20-40 μm.

Embodiment 3: In Embodiment 1, a method for connecting a copper-based alloy and a die steel alloy by a 3D printing method is described. In step 2, the sintering treatment is specifically: using SLM technology to perform laser sintering treatment, The laser power is 300W, the scanning rate is 960mm/s, the scanning interval is 0.11mm, and the number of laser scans is 2 times.

Embodiment 4: The method for connecting a copper-based alloy and a die steel alloy by a 3D printing method described in Embodiment 1. In step 3, the powder used for printing is MS1 die steel powder, and the printing parameters are: The powder thickness is 40μm, the scanning speed is 960mm/s, the printing power of the first and second layers is 265-325W, and each layer is scanned twice by laser, starting from the third layer, the printing power is 285W, and the laser is scanned once until the end of printing.

Embodiment 5: In Embodiment 1, a method for connecting a copper-based alloy and a die steel alloy by a 3D printing method, in step 4, the heat treatment is specifically: direct aging treatment, and the aging temperature is 520°C , The parts are heated with the furnace, the heating rate is 10℃/min, the holding time is 6h, and the cooling method is air cooling.

Example 1:

Step 1: Use traditional processing technology to produce a cylindrical copper-based alloy substrate with a smooth upper and lower surface of Ø20mm×15mm;

Step 2: Use thermal spraying technology to coat a 30-micron-thick nickel layer on the surface to be printed on the base;

Step 3: Perform laser sintering on the nickel-plated surface, the laser power is 300W, the scanning rate is 960mm/s, and the scan is performed twice. After the sintering is completed, the nickel-plated surface is polished to ensure that the nickel-plated surface is level and smooth;

Step 4: Use SLM technology to print cylindrical MS1 mold steel parts with Ø20mm×7mm on the processed substrate. The printing power of the first and second layers of powder is 265W, the scanning rate is 960mm/s, and the powder thickness is 40%. Micron, the scanning distance is 0.11mm, the laser scans twice, and the substrate is preheated to 100°C; starting from the third layer (including the third layer), the printing power is adjusted to 285W, the number of laser scans is adjusted to one, and other parameters remain unchanged;

Step 5. Perform direct aging treatment on the printed connector, the aging temperature is 520°C, the temperature is kept for 6 hours, and the air is cooled;

Step 6: Use wire EDM technology to cut the connector longitudinally along the axis, and obtain the microstructure at the interface between the MS1 die steel and the copper-based alloy through the standard metallographic sample preparation method, as shown in Figure 1.

Example 2: The difference between this example and Example 1 is that the printing power of the first and second layers of powder is 285W, and the others are the same as Example 1. The microstructure at the interface between MS1 die steel and copper-based alloy is shown in Figure 2.

Example 3: The difference between this example and Example 1 is that the printing power of the first and second layers of powder is 305W, and the others are the same as Example 1. The microstructure at the interface between MS1 die steel and copper-based alloy is shown in Figure 3.

Example 4: The difference between this example and Example 1 is that the printing power of the first and second layers of powder is 325W, and the others are the same as Example 1. The microstructure at the interface between MS1 die steel and copper-based alloy is shown in Figure 4.

According to the analysis of Figures 1-4, it can be seen that with the increase of the printing power of the first and second layers, the defects at the connection interface between the copper-based alloy and the MS1 die steel first decreased and then increased, and the defects were the least when the printing power was about 305W. Metal connections are in the best condition.

Claims (5)

1. a method that adopts 3D printing method to realize the connection of copper-based alloy and die steel alloy, it is characterized in that: described method steps are as follows: Step 1: Make a copper-based alloy base according to actual needs, ensure that the surfaces on the base that will be connected to the die steel are on the same plane, and use thermal spraying technology to coat the surface of the base that will be connected to the die steel. a layer of nickel; Step 2: sintering the surface of the nickel-plated layer; Step 3: Use 3D printing technology to print printed parts with different shapes on the substrate according to actual needs; Step 4: Heat treatment of the produced parts. 2. A method for realizing the connection between copper-based alloy and die steel alloy by 3D printing method according to claim 1, characterized in that: in step 1, the thickness of the nickel-plated layer is 20-40 μm. 3. A method for realizing the connection between copper-based alloy and die steel alloy by 3D printing method according to claim 1, characterized in that: in step 2, the sintering treatment is specifically: using SLM technology to carry out laser sintering treatment , the laser power is 300-340W, the scanning rate is 960mm/s, the scanning distance is 0.11mm, and the number of laser scanning is 2 times. 4. A method for realizing the connection between copper-based alloy and die steel alloy by 3D printing method according to claim 1, characterized in that: in step 3, the powder used for printing is MS1 die steel powder, and the printing parameters are: The powder thickness is 40μm, the scanning speed is 960mm/s, the printing power of the first and second layers is 285-325W, and each layer is scanned twice by laser, starting from the third layer, the printing power is 285W, and the laser is scanned once until the end of printing . 5. A method for realizing the connection between copper-based alloy and die steel alloy by 3D printing method according to claim 1, characterized in that: in step 4, the heat treatment is specifically: direct aging treatment, and the aging temperature is 490 ℃ ～520℃, the parts are heated with the furnace, the heating rate is 10℃/min, the holding time is 4～6h, and the cooling method is air cooling.