阅读说明：本技术 基于脉冲电流的3d打印方法及装置 (3D printing method and device based on pulse current ) 是由 赵少凡 张琪 廖超群 白海洋 刘明 董雯 焦志伟 汪卫华 于 2020-12-11 设计创作，主要内容包括：本发明提供一种基于脉冲电流的3D打印方法,以非晶合金丝材或条带为原材料,对其点压后通过脉冲电流进行焊接,逐层堆叠形成三维样件。本发明方法利用脉冲电流作为非晶合金太空增材制造的热源,一方面制造过程中所需功耗远小于电子束、激光等传统热源,提高能量利用率,实现低功耗增材制造；另一方面,脉冲电流快递加热,使非晶合金处于黏度较小的非熔融状态,可避免金属材料传统3D打印方法在微重力下熔池难以控制、高真空环境下散热及凝固困难等问题,可提高太空增材制造过程的稳定性；此外,通过脉冲电流对非晶合金进行点压快速焊接及逐层增材制造,增材制造过程中热作用时间精准可控,不仅可以保持原材料的非晶结构,提高增材样件的力学性能。(The invention provides a pulse current-based 3D printing method, which takes amorphous alloy wires or strips as raw materials, welds the amorphous alloy wires or strips through pulse current after point pressing, and forms a three-dimensional sample piece by layer stacking. The method utilizes the pulse current as the heat source for the amorphous alloy space additive manufacturing, on one hand, the power consumption required in the manufacturing process is far less than that of the traditional heat sources such as electron beams, lasers and the like, the energy utilization rate is improved, and the low-power-consumption additive manufacturing is realized; on the other hand, the pulse current is used for heating rapidly, so that the amorphous alloy is in a non-molten state with low viscosity, the problems that a molten pool is difficult to control under microgravity, heat dissipation and solidification are difficult in a high-vacuum environment and the like in a traditional 3D printing method for metal materials can be solved, and the stability of the space additive manufacturing process can be improved; in addition, spot-pressure rapid welding and layer-by-layer material increase manufacturing are carried out on the amorphous alloy through pulse current, the thermal action time in the material increase manufacturing process is accurate and controllable, the amorphous structure of raw materials can be kept, and the mechanical property of the material increase sample piece is improved.)

1. A3D printing method based on pulse current is characterized in that amorphous alloy wires or strips are used as raw materials, spot pressing is carried out on the amorphous alloy wires or strips through the pulse current, and the amorphous alloy wires or strips are stacked layer by layer to form a three-dimensional product.

2. The pulsed current based 3D printing method according to claim 1, wherein the duration of the pulsed current is 10ms or less and the heating rate is 10⁵K/s or more.

3. The pulsed current based 3D printing method according to claim 2, comprising the steps of:

1) selection of parameters

Taking 100-500A of discharge current, 0.5-10 ms of current pulse width and 0.3-5 kg of pressure value as the welding conditions of the amorphous alloy strip/wire;

2) selection and preparation of amorphous alloy

The amorphous alloy system is Pd, Au, Zr, Ti, Fe, Cu, La, Ce or Mg base;

according to the selected amorphous alloy system, metal raw materials are proportioned according to the atomic proportion, and after uniform smelting, an amorphous alloy strip is prepared by a melt spinning method;

3) electric pulse rapid welding

Under the action of pulse current, the two layers of amorphous alloy strips are quickly heated and welded into a whole under the action of pressure.

4. The utility model provides a 3D printing device based on pulse current, includes the frame, its characterized in that still includes:

the forming device and the control device are arranged in the rack, the control device is in control connection with the forming device, and the control device performs command control on the forming device;

the forming device comprises a transmission device, a metal electrode, a belt wheel and a transmission wheel;

the metal electrode is in transmission connection with the transmission device and is driven by the transmission device to do vertical linear reciprocating motion;

the belt wheel is filled with amorphous alloy materials, and the transmission wheel is arranged between the belt wheel and the metal electrode and used for conveying the amorphous alloy materials in the belt wheel to the position below the metal electrode; and a strip or wire cutting device is arranged, so that the three-dimensional forming of the sample piece in additive manufacturing is facilitated.

5. The pulsed current based 3D printing device according to claim 4, wherein the forming device further has a pressure sensor located below the actuator, directly above the metal electrode, the pressure sensor moving with the movement of the metal electrode.

6. The pulsed current based 3D printing device according to claim 5, wherein the shaping device further has a base plate disposed directly below the metal electrode, the base plate being capable of three-dimensional motion.

7. The pulsed current-based 3D printing apparatus according to claim 6, wherein the control device comprises a constant current source for outputting a pulsed current with a stable magnitude and waveform, the pulsed current is transmitted to the metal electrode through a wire, and then flows back to the constant current source through the non-alloy material and the base plate.

8. The pulsed current based 3D printing device according to claim 7, wherein the command control comprises: the control of the up-and-down linear reciprocating motion of the metal electrode, the control of the pulse current transmission of the metal electrode, the control of the three-dimensional motion of the bottom plate, the control of the transmission speed of the amorphous alloy material and the control of the distance between welding points.

9. The pulsed current based 3D printing device according to any of claims 4 to 8, wherein the control device further comprises a smart touch screen, and the pressure value generated between the metal electrode and the amorphous alloy material, the pitch of the welding point, the pulse current waveform and magnitude, and the setting of the rotation speed of the transfer wheel are manually adjusted by touching the smart touch screen.

10. The pulsed current based 3D printing device according to any one of claims 4 to 8, further comprising a power generation device, wherein the power generation device is installed outside the frame and connected with the printing device through a wire to supply power to the whole printing device.

Technical Field

The invention belongs to the technical field of 3D printing, is suitable for the field of space manufacturing, and particularly relates to a 3D printing method and device based on electric pulses.

Background

The space Additive Manufacturing technology (In-space Additive Manufacturing) facing the space environment, namely 'Manufacturing and serving In space', can break through the severe limit on the load volume, weight and structural strength when a carrier rocket is launched, realizes the on-orbit Manufacturing of spacecraft structures with different sizes and complex shapes, and improves the flexibility of executing space missions. Meanwhile, in the space microgravity environment, the structure and strength design of the spacecraft can be simplified, and the large structure manufactured by small equipment is realized. Therefore, the development of the space additive manufacturing technology is a strategic requirement of seizing space competition and high-point control of all countries, and is beneficial to promoting the development of moon and deep space exploration, manned space engineering, on-orbit maintenance and national defense military strength in China.

At present, the cabin additive manufacturing technology which adopts thermoplastic polymer and fiber reinforced composite materials as raw materials has made breakthrough progress at home and abroad. NASA has been reported to achieve in-cabin additive manufacturing of thermoplastic polymer materials in international space stations (msw) in 2014 using Fused Deposition Modeling (FDM). In 2020, an FDM additive manufacturing system of a continuous fiber reinforced composite material is developed by Beijing satellite manufacturing factory Co., Ltd, which is a Chinese space technology research institute, and an in-orbit experiment of the first space additive manufacturing technology in China is completed through a new generation manned spacecraft test ship independently developed in China.

The additive manufacturing technology for breaking through the extravehicular space environment is a key point facing to the large-scale space structure. In 2019, NASA subsidized the "Archinaut One" project (dollars 7370 ten thousand) with the goal of verifying in-orbit the ability of small spacecraft to manufacture 10 meter truss structures on near-earth orbits. Extreme space environments such as high vacuum, microgravity, high and low temperature interaction, strong irradiation and the like all put special requirements on raw materials, processes, devices and the like in the additive manufacturing process. For example, the loss of gravity in the space environment can cause the splashing of raw material molten drops, and the molten pool and the manufacturing process are difficult to control; the high vacuum environment can cause the heat and mass transfer mode of the material to change in the manufacturing process. Therefore, breaking through the space additive manufacturing technology, new materials, new processes, new devices and the like are needed.

The amorphous alloy is a novel metal material discovered in the 60 s of the 20 th century, has a long-range disordered and short-range ordered atomic structure, does not have defects such as dislocation, grain boundary and the like, and has the properties of high strength, high hardness, large elastic deformation limit, radiation resistance, corrosion resistance, high-speed impact resistance and the like; meanwhile, the material has plastic characteristics, and can be subjected to thermoplastic processing in a supercooled liquid-phase temperature region far lower than the melting point of the material, so that the energy consumption required in the manufacturing process is greatly reduced, molten drop splashing caused by a high-energy-consumption heat source in additive manufacturing under the microgravity condition is avoided, and the stability of the manufacturing process is improved. Therefore, the amorphous alloy is an ideal model material for realizing the space additive manufacturing technology of the alloy material.

However, the amorphous structure has a higher energy state than the crystalline structure, which leads to the amorphous alloy having a tendency of crystallization naturally, i.e. the amorphous alloy is heated to a temperature above the glass transition temperature, and crystallization occurs after a period of time, thereby affecting the service performance.

In 2011, William l.johnson, university of california, in the journal of Science, reports that the transition temperature of amorphous alloy Glass can be increased when an amorphous alloy material is rapidly heated by using pulse current, Crystallization behavior is effectively avoided, and a special atomic structure and excellent performance of the amorphous alloy material are maintained (William l.johnson, et al.coating Crystallization in Glass-Forming Metals by millisecond. Science 332(2011)828 + 833.), as shown in fig. 1.

At present, the method for preparing the amorphous alloy sample by using pulse current heating mainly utilizes the characteristic of high temperature rise/drop speed of electric pulse heating to form a softened block amorphous alloy material by pressure. Chinese patent CN206763762U discloses an amorphous alloy forming device based on lorentz force, specifically, it is proposed that a pulse current generated by discharging a capacitor flows through an amorphous alloy to realize rapid heating, when the pulse current is raised to a preset forming temperature, the charged capacitor discharges to a forming coil to generate a magnetic field, and the lorentz force is generated under the combined action of the magnetic field and an induced current flowing in a sample piece of the amorphous alloy, so that the amorphous alloy sample heated to a supercooled liquid region is deformed to a mold for cooling forming under the driving of the lorentz force. However, the method needs to prepare a mold in advance, has high control difficulty, and can only form an amorphous alloy sample with a fixed shape.

Therefore, in order to avoid the molten drop splashing of the alloy material caused by the additive manufacturing of the high-energy-consumption heat source under the microgravity condition, the amorphous alloy material is adopted as the model material for the space additive manufacturing, so that the stability of the manufacturing process can be improved. However, the amorphous alloy material is easily crystallized when heated to a temperature higher than the glass transition temperature. In the prior art and the method, a pulse current is utilized to heat a block amorphous alloy material, and an amorphous alloy sample with a fixed shape can only be formed through a die.

The amorphous alloy material is used as a model material for space additive manufacturing, so that molten drop splashing caused by a high-temperature energy consumption heat source in additive manufacturing under a microgravity condition can be avoided, and the stability of the manufacturing process is improved.

Disclosure of Invention

Therefore, the invention provides a 3D printing method and device based on electric pulses, which not only solve the problem that amorphous alloy materials are easy to crystallize, but also realize the diversity of formed amorphous alloy samples, and provide a new idea for space manufacturing of metal materials.

The invention provides a technical scheme that: A3D printing method based on pulse current is characterized in that amorphous alloy wires or strips are used as raw materials, spot pressing is conducted on the amorphous alloy wires or strips through the pulse current, and the amorphous alloy wires or strips are welded and stacked layer by layer to form a three-dimensional product.

Preferably, the duration of the pulse current is less than or equal to 10ms, and the heating rate is 10⁵K/s or more.

Preferably, the method comprises the following steps:

1) selection of parameters

Using a discharge current of 100-500A, a current pulse width of 0.5-10 ms and a pressure value of 0.3-5 kg as diffusion bonding control conditions of the amorphous alloy strip; the pressure is only used for enabling the strips to be tightly attached, so that spot welding and combination are convenient; the pressure is large, so that metallurgical bonding between the strips is facilitated;

2) selection and preparation of amorphous alloy

The amorphous alloy system is Pd, Au, Zr, Ti, Fe, Cu, La, Ce or Mg base;

according to the selected amorphous alloy system, metal raw materials are proportioned according to the atomic proportion, and after uniform smelting, an amorphous alloy strip is prepared by a melt spinning method;

3) electric pulse rapid welding

The resistivity of the amorphous alloy material is generally higher than that of the traditional crystalline metal material by one order of magnitude; under the action of pulse current, the two layers of amorphous alloy strips are quickly heated and welded into a whole under the action of pressure.

The invention also provides a technical scheme that: A3D printing device based on pulse current, includes the frame, still includes:

the forming device and the control device are arranged in the rack, the control device is in control connection with the forming device, and the control device performs command control on the forming device;

the forming device comprises a transmission device, a metal electrode, a belt wheel and a transmission wheel;

the metal electrode is in transmission connection with the transmission device and is driven by the transmission device to do vertical linear reciprocating motion;

the belt wheel is filled with amorphous alloy materials, the conveying wheel is arranged between the belt wheel and the metal electrode and used for conveying the amorphous alloy materials in the belt wheel to the position below the metal electrode, and the belt material or wire material cutting device is arranged to facilitate three-dimensional forming of an additive manufacturing sample.

Preferably, the forming device is further provided with a pressure sensor, the pressure sensor is positioned below the transmission device and right above the metal electrode, and the pressure sensor moves along with the movement of the metal electrode.

Preferably, the forming apparatus further has a base plate disposed directly below the metal electrode, the base plate being capable of three-dimensional movement.

Preferably, the control device comprises a constant current source for outputting pulse current with stable size and waveform, and the pulse current is transmitted to the metal electrode through a lead and then flows back to the constant current source through the non-alloy material and the bottom plate.

Preferably, the instruction control includes: the control of the up-and-down linear reciprocating motion of the metal electrode, the control of the pulse current transmission of the metal electrode, the control of the three-dimensional motion of the bottom plate, the control of the transmission speed of the amorphous alloy material and the control of the distance between welding points.

Preferably, controlling means still includes intelligent touch display screen, through touch display screen manual adjustment metal electrode and the amorphous alloy material between the pressure value that produces, the interval of welding point, pulse current waveform and size and the settlement of transfer wheel rotation speed.

Preferably, the printing device further comprises a power generation device, wherein the power generation device is installed outside the rack and connected with the printing device through a wire to supply power to the whole printing device.

Has the advantages that:

according to the 3D printing method based on the pulse current, the amorphous alloy wire or strip is used as a raw material, the pulse current is used as a heat source for space additive manufacturing, on one hand, the power consumption required in the manufacturing process is far smaller than that of traditional heat sources such as electron beams and lasers, the energy utilization rate can be improved, the low-power-consumption additive manufacturing is realized, and the stability of the space additive manufacturing process is improved; on the other hand, the amorphous alloy is subjected to point-pressing rapid welding and layer-by-layer additive manufacturing through pulse current, the thermal action time in the additive manufacturing process is accurate and controllable, the amorphous structure of raw materials can be kept, the mechanical property of an additive sample piece is improved, and meanwhile the problems that a molten pool is difficult to control under microgravity, heat dissipation and solidification are difficult in a high-vacuum environment and the like in a traditional 3D printing method for metal materials can be avoided.

In the prior art, attention needs to be paid to avoiding crystallization when amorphous alloy raw materials are used for 3D printing, but crystallization occurs when the amorphous alloy raw materials are heated to a temperature higher than the glass transition temperature in a conventional heating mode, so that how to avoid the crystallization becomes a key point. The amorphous alloy strip charged pulse 3D printing method utilizes the characteristics of short pulse current duration, small discharge area and concentrated energy, and the heating rate can reach 10⁵K/s, far exceeding the critical heating rate (200K/s) for crystallization; the large heating rate can improve the glass transition temperature of the amorphous alloy, increase the thermal stability of the amorphous alloy, effectively avoid crystallization behavior and keep the special atomic structure and excellent performance of the amorphous alloy. In addition, the method can adapt to amorphous alloy wires/strips of different systems by adjusting the pulse current and the waveform.

The invention provides a 3D printing device based on pulse current, which comprises a rack, a forming device and a control device, wherein the forming device and the control device are arranged in the rack, and the control device is in control connection with the forming device and performs instruction control on the forming device. Under the control of a control device, a conveying wheel of a forming device conveys amorphous alloy materials to the position under a metal electrode at a certain rotating speed, the metal electrode is driven by a transmission device to do vertical linear reciprocating motion under the control of the control device and is in mutual contact with the amorphous alloy materials to generate certain pressure, when the measured pressure value is the set value of the control device, the control device controls a constant current source to output pulse current to flow to the amorphous alloy materials through the metal electrode, and the amorphous alloy materials are heated to be above the glass transition temperature due to the sudden increase of the resistance at the interface of the amorphous alloy materials and realize the diffusion bonding between the amorphous alloy materials under the action of the pressure to generate a welding point; the complete combination of the amorphous alloy materials among layers can be realized by controlling the distance of the welding points, and the forming bottom plate does three-dimensional motion under the control of the control device so as to realize the additive manufacturing layer by layer and form an amorphous alloy product. Not only realizes the forming integration and is not limited by the shape of the die, but also avoids the oxidation and crystallization which are easy to occur in the forming process of the non-gold alloy.

Drawings

In order that the present disclosure may be more readily and clearly understood, reference will now be made in detail to the present disclosure, examples of which are illustrated in the accompanying drawings.

FIG. 1 is a graph illustrating the effect of heating rate on crystallization behavior of an amorphous alloy in a supercooled liquid temperature range according to the prior art;

FIG. 2 is a schematic diagram of an amorphous alloy 3D printing device based on pulse current according to an embodiment of the invention;

FIG. 3 is a schematic diagram of a forming device in an amorphous alloy 3D printing apparatus based on pulse current according to an embodiment of the invention;

FIG. 4 is a diagram of an article in which pulsed current effects welding between two layers of Fe-based, La-and Zr-based amorphous alloy strips;

FIG. 5 is an XRD result chart of Fe-based, La-based and Zr-based amorphous alloys before and after welding.

In the figure: 1-a power generation device; 2-a control device; 3-belt wheel; 4-a transmission device; 5-a transfer wheel; 6-a pressure sensor; 7-a metal electrode; 8-a frame; 9-a motion platform; 10-preparation of a product; 11-amorphous alloy strip/wire.

Detailed Description

The present invention will be further described with reference to the accompanying drawings for illustrating the technical contents, objects and effects of the present invention in detail, it should be understood that the present invention is only for explaining the present invention and is not limited thereto.

According to the 3D printing method based on the pulse current, amorphous alloy wires or strips are used as raw materials, spot pressing is carried out on the amorphous alloy wires or strips through the pulse current, welding is carried out, and the amorphous alloy wires or strips are stacked layer by layer to form a three-dimensional product. When a pulse current flows through the amorphous alloy strip/wire, the amorphous alloy strip/wire is heated to a temperature above the glass transition temperature due to the sudden increase of the resistance at the amorphous alloy strip/wire interface, and diffusion bonding between the amorphous alloy strip/wire is realized under the action of pressure. Specifically, a metal electrode is used for carrying out electric pulse rapid discharge to pass through two layers/multiple layers of amorphous alloy strips/wires, when current passes through the amorphous alloy strips/wires, the resistance is suddenly increased, and heat is generated to heat the amorphous alloy strips/wires; and meanwhile, the metal electrode applies certain pressure to the welding area to enable the layers to be in close contact with each other while discharging rapidly, atomic diffusion metallurgical bonding is generated, rapid welding is achieved, the process is equivalent to the interlayer stacking process of the 3D printing technology, and the required three-dimensional product can be formed through the layer-by-layer stacking process.

Further, the duration time of the pulse current in this embodiment is 10ms or less, and the heating rate is 10⁵K/s or more. The amorphous alloy strip electric pulse 3D printing utilizes the characteristics of short pulse current duration (less than or equal to 10ms), small discharge area and concentrated energy, and the heating rate can reach 10⁵More than K/s, compared with the traditional heating mode (less than or equal to 10)²K/s) is several orders of magnitude larger and the heat distribution is uniform, thus avoiding crystallization behavior (critical heating rate of about 200K/s bypassing crystallization completely), and obtaining supercooled liquid above the melting point; meanwhile, the resistivity of the amorphous alloy is higher than that of the traditional crystalline alloy material, the temperature coefficient is small and is negative, and under the action of higher current density and ohmic dissipation, the heating of the amorphous alloy tends to be localized in space, namely the amorphous alloy can be heated to the required temperature within ten milliseconds. Therefore, in the embodiment, the transition temperature of the amorphous alloy glass can be increased through a large heating rate, the thermal stability of the amorphous alloy glass is increased, the crystallization behavior is effectively avoided, and the special atomic structure and the excellent performance of the amorphous alloy glass are maintained. In addition, the method can adapt to amorphous alloy wires/strips of different systems by adjusting the pulse current and the waveform. The amorphous alloy system used by the invention can be Pd, Au, Zr, Ti, Fe, Cu, La, Ce, Mg-based amorphous alloy with thermoplastic forming capability and the like, and is suitable for different amorphous alloy wires or strips by adjusting the parameter settings of the capacitor capacity and the discharge currentA substrate. The metal electrode used may be a copper electrode, specifically brass, copper, tungsten copper, or the like.

Example 1

In the embodiment, the welding among the Fe-based, La-based and Zr-based amorphous alloy strips is realized through the pulse current and the amorphous characteristics are maintained, referring to fig. 4, a product diagram of the welding among the Fe-based, La-based and Zr-based amorphous alloy strips is shown, referring to fig. 5, XRD result diagrams before and after the welding among the Fe-based, La-based and Zr-based amorphous alloy strips are shown, which proves that the welded product still maintains the amorphous structure; the method comprises the following specific steps:

1. selection of parameters

Fe-based amorphous alloy ribbon: a4700 muF capacitor is selected, and a discharge current of 200A, a current pulse width of 0.5ms, a welding point interval of 0.5mm and a pressure value of 3.5kg are used as diffusion bonding control conditions of the amorphous alloy strip.

La-based amorphous alloy ribbon: a4700 muF capacitor is selected, and a discharge current of 400A, a current pulse width of 1ms, a welding point interval of 0.5mm and a pressure value of 4kg are used as the diffusion bonding control conditions of the amorphous alloy strip.

Zr-based amorphous alloy ribbon: a4700 muF capacitor is selected, and a discharge current of 400A, a current pulse width of 1ms, a welding point interval of 0.5mm and a pressure value of 4kg are used as the diffusion bonding control conditions of the amorphous alloy strip.

2. Selection and preparation of amorphous alloy

The optional amorphous alloy system can be Pd, Au, Zr, Ti, Fe, Cu, La, Ce, Mg-based amorphous alloy with thermoplastic forming capability and the like.

In this test, the alloy system is Fe_73.5Cu₁Nb₃Si_13.5B₉、La₆₀Ni₁₅Al₂₅、Zr_64.13Cu_15.75Ni_10.12Al₁₀The description is given for the sake of example. According to the selected amorphous alloy system, metal raw materials are proportioned according to the atomic proportion, and after being uniformly smelted, Fe with the width of 5mm and the thickness of 25 mu m is respectively prepared by a melt spinning method_73.5Cu₁Nb₃Si_13.5B₉An amorphous alloy strip; width 3mm, thickness 120La of μm₆₀Ni₁₅Al₂₅A strip; zr with a width of 2mm and a thickness of 100 μm_64.13Cu_15.75Ni_10.12Al₁₀A strip.

3. Electric pulse rapid welding

Under the action of pulse current, the two layers of amorphous alloy strips are quickly heated to a supercooled liquid phase region and are welded into a whole under the action of pressure.

In this embodiment, the rate of heating the amorphous alloy by the pulse current can reach 10⁵K/s and the heat is distributed evenly; meanwhile, the amorphous alloy has high resistivity (100-250 mu omega cm), the temperature coefficient is small and is negative, under the action of high current density and ohmic dissipation, the heating of the amorphous alloy tends to be localized spatially, that is, the amorphous alloy can be heated to the required temperature within ten milliseconds, and the possible oxidation and crystallization of the amorphous alloy in the forming process are effectively avoided. The processes of heating, welding and cooling of the amorphous alloy strip are almost completed within one-time millisecond pulse discharge, and the method has the advantage of integration of heating, welding and cooling.

The temperature rise of the amorphous alloy strip is controlled by the discharge waveform, and further explained as that if other electrical parameters (such as line resistance, amorphous alloy strip resistance and the like) are determined, the temperature rise of the amorphous alloy strip is determined by the capacitor capacity and the discharge current, so that the amorphous alloy strip can adapt to different amorphous alloy systems, and is convenient to regulate and control.

Example 2

The embodiment is a 3D printing device based on pulse current, and is shown in fig. 2 and fig. 3, and comprises a rack 8, a forming device and a control device 2, wherein the rack is formed by mounting aluminum alloy, the forming device and the control device are arranged in the rack 8, the control device 2 is in control connection with the forming device, and the control device sends an instruction to the forming device through a data line/wireless communication device to perform real-time control. The forming device comprises a transmission device 4, a metal electrode 7, a belt wheel 3 and a transmission wheel 5, wherein the metal electrode 7 is in transmission connection with the transmission device 4 and is driven by the transmission device 4 to do linear reciprocating motion up and down; the belt wheel 3 is filled with amorphous alloy materials, the conveying wheel 5 is arranged between the belt wheel 3 and the metal electrode 7 and used for conveying the amorphous alloy materials in the belt wheel 3 to the position below the metal electrode 7, and a strip or wire cutting device (not shown) is further arranged and used for cutting off the amorphous alloy materials so as to facilitate three-dimensional forming of the material increase manufacturing sample, for example, the strip or wire cutting device is arranged beside the metal electrode 7 or the arrangement position can be changed, and when the amorphous alloy materials need to be cut off, the cutting device is started to cut off the amorphous alloy materials. If the position needs to be changed for printing during printing, the cutting device is started to cut off the amorphous alloy material, and the amorphous alloy material is printed after the position is found; for another example, when the printing is finished, the cutting device is started to cut off the amorphous alloy material, and the sample piece is completed.

The amorphous alloy material used in this embodiment is preferably an amorphous alloy ribbon/wire 11. In the 3D printing device based on pulse current of this embodiment, under the control of the control device 2, the transmission wheel 5 conveys the amorphous alloy strip/wire 11 to the position under the metal electrode 7 at a certain rotation speed, the metal electrode 7 is driven by the control device 2 to do vertical linear reciprocating motion under the drive of the transmission device 4, and contacts with the amorphous alloy strip/wire 11 to generate a certain pressure, when the pressure value is a set value of the control device 2, the control device 2 controls the constant current source to output pulse current to flow to the amorphous alloy strip/wire 11 through the metal electrode 7, because the resistance at the interface of the strip/wire 11 is suddenly increased, the amorphous alloy strip/wire 11 is heated to a temperature above the glass transition temperature, and diffusion bonding between the amorphous alloy strip/wire 11 is realized under the pressure to generate a welding point; the interlayer amorphous alloy strips/wires 11 can be completely combined by controlling the distance of welding points, and then the forming bottom plate 9 performs three-dimensional motion under the control of the control device 2 to realize the additive manufacturing layer by layer, so that the amorphous alloy product 10 is formed. The device realizes the forming integration, does not need a mould and is not limited by the shape of the mould, and can print a reticular amorphous alloy product if the parameter control is carried out; oxidation and crystallization of the non-gold alloy that easily occurs during the forming process are also avoided.

Further, a pressure sensor 6 is further disposed in the forming device in this embodiment, the pressure sensor 6 is located below the transmission device 4 and directly above the metal electrode 7, in this embodiment, the metal electrode 7 is fixedly connected to the pressure sensor 6, the pressure sensor 6 is fixedly connected to the transmission device 4, and the pressure sensor 6 moves along with the movement of the metal electrode 7, that is, under the control of the control device 2, the transmission device 4 drives the pressure sensor 6 and the metal electrode 7 to reciprocate up and down. The metal electrode 7 generates certain pressure on the amorphous alloy strip/wire 11 in the up-and-down movement, and the pressure value can be measured by the pressure sensor 6 and adjusted by the control device. Diffusion bonding between the amorphous alloy strips/wires 11 is achieved under pressure, producing a weld.

Further, in the forming device of the present embodiment, a bottom plate 9 is further disposed under the metal electrode 7, and the bottom plate 9 can perform three-dimensional motion under the control of the control device 2, so as to implement additive manufacturing layer by layer, and form an amorphous alloy product.

In this embodiment, the control device 2 includes a constant current source, and is controlled to output a pulse current with a stable magnitude and waveform, and the pulse current is transmitted to the metal electrode 7 through a wire under the control of the control device, and then flows back to the constant current source through the non-gold alloy strip/wire and the bottom plate. The pulse current has short duration, small discharge area, concentrated energy and fast heating rate, far exceeds the in-situ heating rate of the amorphous alloy material for crystallization, and is suitable for amorphous alloy materials of different systems.

In this embodiment, the instruction control by the control device 2 includes:

1) controlling the up-and-down linear reciprocating motion of the metal electrode 7, namely controlling a pressure value generated between the metal electrode 7 and the amorphous alloy strip/wire 11 in the up-and-down motion process of the metal electrode 7, and when the pressure value reaches a preset value, starting diffusion bonding between the amorphous alloy strip/wire 11 and generating a welding point; setting the pressure value to different preset values according to different amorphous alloy materials, wherein the pressure value is preset to 3.5kg when Fe-based amorphous alloy strips are adopted, and the pressure value is preset to 4kg when La or Zr-based amorphous alloy strips are adopted; measuring the magnitude of the applied pressure value by a pressure sensor 6;

2) controlling the metal electrode 7 to transmit pulse current, namely controlling the constant current source to output pulse current to flow to the amorphous alloy strip/wire material 11 through the metal electrode 7 and flow to the constant current source through the bottom plate 9;

3) controlling the three-dimensional motion of the bottom plate 9, namely controlling the bottom plate 9 to do the three-dimensional motion so as to realize the additive manufacturing layer by layer and form an amorphous alloy product;

4) controlling the transmission speed of the amorphous alloy strips/wires 11, namely, the amorphous alloy strips/wires 11 in the belt wheel 3 are conveyed to the position right below the metal electrode 7 at a certain conveying speed under the driving of the conveying wheel 5, and the conveying speed is adjusted by controlling the rotating speed of the conveying wheel 5 by the control device 2;

the transmission speed, the up-and-down linear reciprocating speed of the metal electrode and the three-dimensional movement speed of the bottom plate are matched with each other to work;

5) and controlling the distance of welding points, wherein the position of the metal electrode 7 contacting with the amorphous alloy strip/wire 11 in the downward movement process is the welding point, when the distance of the welding point reaches a preset value, the amorphous alloy strip/wire between layers is in diffusion bonding, and meanwhile, the bottom plate 9 does three-dimensional movement under the control of the control device and adjusts the distance of the welding point so as to realize layer-by-layer additive manufacturing, and an amorphous alloy product is formed.

The control device 2 controls the five aspects and the five aspects are matched with each other, so that 3D printing is realized.

In addition, the control device 2 in this embodiment is further provided with an intelligent touch display screen, and according to the difference of raw material systems, the pressure value generated between the metal electrode 7 and the amorphous alloy strip/wire 11, the pitch of the welding points, the pulse current waveform and size, and the rotation speed of the transfer wheel 5 can be manually set through the intelligent touch display screen. Preferably, the control device 2 is provided with software, and 3D printing can be realized only by inputting the sliced model into the control device 2. 3D printing and forming integration and accurate control can be realized only by setting parameter values on the intelligent touch display screen.

In this embodiment, the power generation device 1 is further included, is installed outside the rack 8, is connected with the 3D printing device through an electric wire, and supplies power to the whole device. The actuators 4 in the forming device may be mechanical actuators, hydraulic actuators and pneumatic actuators. The power generation device 1 can be a photovoltaic power generation panel, and can convert solar energy into electric energy under the sunlight illumination to supply power for the whole device.

In this embodiment, the amorphous alloy system used may be an amorphous alloy having thermoplastic moldability, such as Pd, Au, Zr, Ti, Fe, Cu, La, Ce, Mg-based, and the like. The amorphous alloy system of different systems can be adapted by adjusting the pulse current and the waveform.

In this embodiment, before the 3D printing apparatus works, the pressure value between the metal electrode and the amorphous alloy material, the distance between the welding points, the waveform and size of the pulse current, and the transmission speed of the transmission wheel are preset, when the 3D printing apparatus starts to work, the constant current source is controlled to output the pulse current to the amorphous alloy strip/wire through the metal electrode, the metal electrode is controlled by the control apparatus to perform a vertical linear reciprocating motion to apply a pressure to the amorphous alloy strip/wire therebelow, when the pressure value reaches a preset value, diffusion bonding starts between the amorphous alloy strip/wire, the contact position between the metal electrode and the amorphous alloy strip/wire therebelow is the welding point, the amorphous alloy strip/wire is completely bonded at the distance reaching the preset welding point, and the bottom plate performs a three-dimensional motion under the control of the control apparatus to further realize layer-by, and forming the amorphous alloy product.

The 3D printing device does not need to use a mold, so the device is not limited by the shape of the mold, and can realize diversified and multi-shaped amorphous alloy products through parameter setting, for example, a reticular amorphous alloy product can be printed through parameter control; the 3D printing and forming integration and accurate control are realized, and the possible oxidation and crystallization of the amorphous alloy in the forming process are effectively avoided.

In the environment of outer space, the most important influencing factors for 3D printing are high vacuum and microgravity environment. The 3D printing method based on the pulse current is characterized in that on one hand, the raw material used is a wire or a strip instead of a powder material used in the traditional technology; on the other hand, the amorphous alloy is subjected to point-pressing rapid welding and layer-by-layer additive manufacturing through pulse current, and the thermal action time in the additive manufacturing process is accurate and controllable, so that the 3D printing method disclosed by the invention not only can keep the amorphous structure of the raw material and improve the mechanical property of the additive sample piece, but also can avoid the problems that a molten pool is difficult to control under microgravity, the heat dissipation and solidification are difficult in a high-vacuum environment and the like in the traditional 3D printing method for metal materials. Therefore, the technical scheme of the pulse current-based 3D printing method and device is researched and developed based on the outer space environment, and the technical scheme completely meets the additive manufacturing task in the outer space environment.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.