Device for manufacturing heterogeneous material progressive interface and control method

Abstract

The invention discloses a device for manufacturing a progressive interface of a heterogeneous material and a control method, and relates to the technical field of laser additive manufacturing. The mixing uniformity of components in a heterogeneous material transition region is remarkably improved, and the size and distribution uniformity of grains and a brittle second phase in a heterogeneous interface transition region are reduced, so that the mechanical property of a heterogeneous material connection region is remarkably improved. And meanwhile, the double-barrel powder feeder and the spiral powder mixing stirrer are adopted, uneven mixing caused by large density difference of heterogeneous materials is avoided, online real-time adjustment and conveying of the metal powder in the progressive mixing proportion can be achieved, and cracking caused by interface component mutation due to component gradient step length of the mixed powder is avoided. On the basis, progressive transition of titanium alloy-transition interface-aluminum alloy components is formed, effective connection of heterogeneous materials with large physical property parameter differences is achieved, and then integrated composite forming of the heterogeneous alloy and large complex structural parts can be achieved.

Description

Technical Field

[0001] The present application relates to the field of laser additive manufacturing technology, and in particular to a device and a control method for manufacturing a progressive interface of heterogeneous materials. Background Art

[0002] With the continuous development of aerospace technology, the new generation of aircraft is also developing towards high speed, long range and high maneuverability, which puts forward more stringent requirements on the weight, strength and reliability of product structures. However, the preparation and welding of heterogeneous alloy materials will generate an interface layer containing a large amount of brittle intermetallic compounds, which greatly reduces the reliability of the composite component during service. At present, the integrated composite structure of titanium and aluminum heterogeneous alloy materials can give full play to the performance advantages of the two materials and make up for each other's shortcomings. It is widely used in aerospace and transportation fields. However, the physical and chemical properties of titanium and aluminum alloys such as density, melting point, linear expansion coefficient and thermal conductivity coefficient are quite different. At the same time, titanium alloy and aluminum alloy will react chemically after melting and generate hard and brittle TiAl (an emerging metal compound structural material) intermetallic compounds, which weakens the bonding strength of the interface layer, resulting in a sharp decline in the mechanical properties of the Ti / Al joint, which seriously limits the stable application of Ti / Al bimetallic integrated structural parts in industry.

[0003] In the related art, ultrasonic and preheating assisted laser deposition is used for connection, or tungsten inert gas arc heat source is used to melt aluminum alloy welding wire to form a connection with titanium alloy. However, the applicant has realized that as the height of the deposited part increases, the amplitude of the single ultrasonic field decreases significantly and the heat accumulation gradually increases, resulting in obvious growth and coarsening of the brittle phase, and the mechanical properties of the transition zone of the heterogeneous material are not high; and the connection using tungsten inert gas arc belongs to liquid-solid connection rather than metallurgical bonding, and the mechanical properties of its transition zone are not high. When preparing large load-bearing structural parts, there are still limitations of poor reliability and low fatigue performance. Summary of the invention

[0004] In view of this, the present application provides a device and a control method for manufacturing a progressive interface of heterogeneous materials. The main purpose is to solve the problem that the mechanical properties of the transition zone of heterogeneous materials are not high, and there are still limitations such as poor reliability and low fatigue performance when preparing large load-bearing structural parts.

[0005] According to the first aspect of the present application, a device for manufacturing a progressive interface of heterogeneous alloy materials is provided, comprising a double-barrel powder feeder, a spiral powder mixer, a laser head, and an ultrasonic electromagnetic assisted laser additive manufacturing device:

[0006] The double-barrel powder feeder is connected to the spiral powder mixer and is used to feed titanium alloy powder and aluminum alloy powder to the spiral powder mixer according to the alloy powder ratio set in real time;

[0007] The spiral powder mixing agitator is connected to the laser head and is used to mix the titanium alloy powder and the aluminum alloy powder to obtain alloy mixed powder;

[0008] The laser head is used to move from one side of the titanium alloy substrate to the side of the aluminum alloy substrate according to a scanning set speed and place the alloy mixed powder in a molten pool, and to emit laser to the molten pool according to a laser set power and the scanning set speed, perform laser deposition operation on the molten pool, and obtain a progressive interface of heterogeneous alloy materials;

[0009] The ultrasonic electromagnetic assisted laser additive manufacturing device is placed under the laser head and is used to continuously use ultrasonic waves and electromagnetic fields to act on the molten pool during the laser deposition operation.

[0010] Optionally, the ultrasonic electromagnetic assisted laser additive manufacturing device includes an ultrasonic vibration system, a direct current electromagnetic system and an ultrasonic vibration platform:

[0011] The ultrasonic vibration system is placed on the ultrasonic vibration platform and is used to generate the ultrasonic wave, and use the ultrasonic wave to diffuse heat from the molten pool;

[0012] The DC electromagnetic system is placed on the ultrasonic vibration platform and is used to generate the electromagnetic field, and the molten pool is stirred by the electromagnetic field;

[0013] A processing platform is arranged on the upper surface of the ultrasonic vibration platform, and the processing platform is used for placing the titanium alloy substrate and the aluminum alloy substrate.

[0014] Optionally, the ultrasonic vibration system includes an ultrasonic generator, an ultrasonic transducer and an ultrasonic probe:

[0015] The ultrasonic generator is connected to the four ultrasonic transducers respectively, and is used to generate a high-frequency alternating current signal matching the ultrasonic transducers;

[0016] Each of the ultrasonic transducers is connected to an ultrasonic probe for converting the high-frequency alternating current signal into the ultrasonic wave, and the vibration direction of the ultrasonic wave is parallel to the axis direction of the four ultrasonic transducers;

[0017] The ultrasonic probe is used to transmit the ultrasonic wave.

[0018] Optionally, the DC electromagnetic system includes a DC electromagnetic field generator, a power control cabinet and a water cooling system:

[0019] The DC electromagnetic field generator is composed of a first water-cooled copper coil and a second water-cooled copper coil, and is used to generate an electromagnetic field. The first water-cooled copper coil and the second water-cooled copper coil are placed opposite to each other on the ultrasonic vibration platform, and the first water-cooled copper coil and the second water-cooled copper coil are slidably connected to the ultrasonic vibration platform.

[0020] The power control cabinet is connected to the DC electromagnetic field generator and is used to control the electromagnetic field induction intensity generated by the DC electromagnetic field generator through input current;

[0021] The water cooling system is connected to the DC electromagnetic field generator and is used to cool the DC electromagnetic field generator.

[0022] Optionally, the double-drum powder feeder includes a titanium alloy powder feeder and an aluminum alloy powder feeder:

[0023] The titanium alloy powder feeding cylinder is connected to the spiral powder mixing agitator through a titanium alloy powder feeding pipe, and is used to feed the titanium alloy powder according to the rotation speed of the titanium alloy powder feeding cylinder;

[0024] The aluminum alloy powder feeding barrel is connected to the spiral powder mixing agitator through an aluminum alloy powder feeding tube, and is used to feed the aluminum alloy powder according to the rotation speed of the aluminum alloy powder feeding barrel, wherein the rotation speed of the titanium alloy powder feeding barrel and the rotation speed of the aluminum alloy powder feeding barrel are calculated based on the real-time set ratio of the alloy powders.

[0025] Optionally, the spiral powder mixer comprises a cylindrical rod and a plurality of spiral blades axially arranged on the cylindrical rod.

[0026] Optionally, the laser head includes a laser powder feeding head and a laser:

[0027] The laser powder feeding head is used to move from one side of the titanium alloy substrate to one side of the aluminum alloy substrate according to a scanning set speed and place the alloy mixed powder in the molten pool;

[0028] The laser emits laser to the molten pool according to the laser setting power and the scanning setting speed, performs laser deposition operation on the molten pool, and obtains a progressive interface of heterogeneous alloy materials.

[0029] Optionally, the apparatus for manufacturing a progressive interface of heterogeneous alloy materials operates under an argon atmosphere.

[0030] According to a second aspect of the present application, a control method for manufacturing a progressive interface of heterogeneous materials is provided, which is applied to a device for manufacturing a progressive interface of heterogeneous alloy materials, comprising:

[0031] Filling argon gas into a sealed frame structure to which a titanium alloy substrate and an aluminum alloy substrate are fixed, starting an ultrasonic vibration system according to vibration setting parameters, and when it is detected that the vibration current and vibration frequency of the ultrasonic vibration system tend to be stable, starting a DC electromagnetic system according to electromagnetic setting parameters;

[0032] The laser is controlled to emit laser according to the laser setting power to form a molten pool at the connection between the titanium alloy substrate and the aluminum alloy substrate, and the double-barrel powder feeder is continuously controlled to feed the titanium alloy powder and the aluminum alloy powder into the spiral powder mixing stirrer for mixing according to the alloy powder ratio set in real time to obtain alloy mixed powder;

[0033] Controlling the laser powder feeding head to move from the titanium alloy substrate side to the aluminum alloy substrate side and placing the alloy mixed powder in the molten pool, wherein during the movement from the titanium alloy substrate side to the aluminum alloy substrate side, the mass of the titanium alloy powder in the alloy mixed powder gradually decreases, and the mass of the aluminum alloy powder in the alloy mixed powder gradually increases;

[0034] The laser is controlled to perform laser deposition on a molten pool containing the alloy mixed powder to obtain a progressive interface of heterogeneous materials, wherein during the laser deposition operation, the ultrasonic vibration system continuously diffuses heat from the molten pool and the DC electromagnetic system continuously stirs the molten pool.

[0035] Optionally, the step of continuously controlling the double-drum powder feeder to feed the titanium alloy powder and the aluminum alloy powder into the spiral powder mixer for mixing according to the alloy powder ratio set in real time to obtain the alloy mixed powder comprises:

[0036] Obtaining the alloy powder ratio at the current moment, and adjusting the rotation speed of the titanium alloy powder feeding barrel and the rotation speed of the aluminum alloy powder feeding barrel according to the alloy powder ratio at the current moment, so that the titanium alloy powder feeding barrel in the double-barrel powder feeder delivers the titanium alloy powder at the rotation speed of the titanium alloy powder feeding barrel, and the aluminum alloy powder feeding barrel in the double-barrel powder feeder delivers the aluminum alloy powder at the rotation speed of the aluminum alloy powder feeding barrel;

[0037] After the double-drum powder feeder feeds the titanium alloy powder and the aluminum alloy powder into the spiral powder mixer, the multiple spiral blades of the spiral powder mixer are used to divide the titanium alloy powder and the aluminum alloy powder multiple times to obtain the alloy mixed powder.

[0038] By means of the above technical scheme, the present application provides a device and a control method for manufacturing a progressive interface of heterogeneous materials, and the present application includes a double-barrel powder feeder, a spiral powder mixer, a laser head, and an ultrasonic and electromagnetic-assisted laser additive manufacturing device: the double-barrel powder feeder is connected to the spiral powder mixer, and is used to feed titanium alloy powder and aluminum alloy powder to the spiral powder mixer according to the alloy powder ratio set in real time; the spiral powder mixer is connected to the laser head, and is used to mix the titanium alloy powder and the aluminum alloy powder to obtain an alloy mixed powder; the laser head is used to move from one side of the titanium alloy substrate to the other side of the aluminum alloy substrate according to a scanning set speed and place the alloy mixed powder in a molten pool, and to emit a laser to the molten pool according to a laser set power and a scanning set speed, perform a laser deposition operation on the molten pool, and obtain a progressive interface of heterogeneous alloy materials; the ultrasonic and electromagnetic-assisted laser additive manufacturing device is placed under the laser head, and is used to continuously use ultrasonic waves and electromagnetic fields to act on the molten pool during the laser deposition operation. This application adopts an ultrasonic electromagnetic assisted laser additive manufacturing device. Under the coupling effect of ultrasonic and electromagnetic fields on the stirring of the molten pool flow field and the braking effect, the uniformity of the mixing of the components in the transition zone of the heterogeneous materials is significantly improved, and the size and distribution uniformity of the grains and brittle second phases in the transition zone of the heterogeneous interface are reduced, thereby significantly improving the mechanical properties of the heterogeneous material connection zone. The use of a double-barrel powder feeder and a spiral powder mixer can avoid the problem of uneven mixing caused by the large density difference of the heterogeneous materials, and avoid the local poor fusion caused by component segregation. At the same time, it can also realize online real-time adjustment of the metal powder with a progressive mixing ratio, and avoid the problem of cracking caused by the gradual change step length of the mixed powder component with the interface component mutation. Based on this, a gradual transition of titanium alloy-transition interface-aluminum alloy components is formed, reducing the phase change stress level caused by the difference in the physicochemical properties of heterogeneous alloys and the interface component mutation, so that heterogeneous materials with large differences in physical parameters can be effectively connected, thereby realizing the integrated composite forming of heterogeneous alloys and large complex structural parts.

[0039] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0041] Figure 1A schematic diagram of the structure of a device for manufacturing a progressive interface of heterogeneous materials provided in an embodiment of the present application is shown;

[0042] Figure 2 A schematic flow chart of a control method for manufacturing a progressive interface of heterogeneous materials provided in an embodiment of the present application is shown;

[0043] Figure 3A A schematic flow chart of another control method for manufacturing a progressive interface of heterogeneous materials provided in an embodiment of the present application is shown;

[0044] Figure 3B A schematic diagram of gradient transition and progressive transition of the interface area provided in an embodiment of the present application is shown;

[0045] Figure 3C A schematic diagram showing microhardness of interface gradient transition and interface progressive transition provided in an embodiment of the present application is shown;

[0046] Figure 3D A schematic diagram showing tensile strength of interface gradient transition and interface progressive transition provided in an embodiment of the present application is shown;

[0047] Figure 3E A schematic diagram of the brittle phase distribution of the titanium alloy and aluminum alloy gradient transition TiAl system provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0048] The exemplary embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present application and to fully convey the scope of the present application to those skilled in the art.

[0049] In the prior art, ultrasonic and preheating assisted laser melting of metal powder is used to generate a heterogeneous material transition zone. However, as the height of the deposited part increases, the amplitude of the single ultrasonic field decreases significantly, the heat accumulation gradually increases, and the brittle phase grows and coarsens significantly. Moreover, when the powder ratio is changed in steps of 10% for powder feeding, there is still a problem of a wide composition transition zone, and there is still an obvious composition mutation between adjacent step interfaces, which has certain limitations for preparing a high-reliability transition zone. In addition, the prior art also uses a tungsten-arc heat source to melt aluminum alloy welding wire to form a connection with a titanium alloy. Although this method can reduce the thickness of the brittle metal intermetallic compound layer in the interface area to a certain extent, this connection belongs to a liquid-solid connection rather than a metallurgical connection. When preparing large load-bearing structural parts, there are still limitations of poor reliability and low fatigue performance. In addition, the prior art also proposes a method of applying a longitudinal magnetic field at the bottom of the deposition platform and adding an interlayer system to improve the connection performance at the interface of the aluminum / steel composite structure. However, the method of applying a magnetic field at the bottom severely limits the size of the prepared workpiece, and the introduction of the third interlayer material changes the composition gradient of the transition zone, which still has certain limitations for obtaining a high-reliability interface.

[0050] To solve the above problems, the present application proposes a device for manufacturing a progressive interface of heterogeneous materials and a control method thereof. Through online real-time control of the powder ratio and an optimal external field assisted process including an ultrasonic vibration system and a DC electromagnetic system, precise control of the thickness of the interface layer and the size and morphology of the brittle phase in the transition zone of the heterogeneous materials is achieved. Ultrasonic vibration and electromagnetic guidance produce acoustic streaming effect, acoustic cavitation effect, vibration stirring effect and electromagnetic braking effect, which effectively reduce the porosity inside the deposition component and improve the uniformity of the distribution of heterogeneous nucleation particles in the melt. At the same time, the grain size is reduced, which is beneficial to fragment the primary TiAl-based brittle phase inside the molten pool and make it evenly distributed in the matrix, reducing the cracking tendency caused by the segregation of large-sized brittle phases at the interface, thereby increasing the effective bearing area of ​​the metal in the interface connection zone and achieving the effect of mass strengthening of fine hard and brittle phases.

[0051] The present application embodiment provides a device for manufacturing a progressive interface of heterogeneous materials, such as Figure 1 As shown, it includes a double-barrel powder feeder 1, a spiral powder mixing and stirring device 2, a laser head 3, and an ultrasonic electromagnetic assisted laser additive manufacturing device:

[0052] The double-drum powder feeder 1 is connected to the spiral powder mixer 2, and is used to feed titanium alloy powder and aluminum alloy powder to the spiral powder mixer 2 according to the alloy powder ratio set in real time, wherein the computer calculates the mass of titanium alloy powder and aluminum alloy powder to be fed online in real time, so that the double-drum powder feeder 1 can feed the mixed alloy powder of the corresponding ratio online in real time, which can solve the problem that the gradual change step length of the mixed alloy powder composition is very limited.

[0053] The spiral powder mixer 2 is connected to the laser head 3 through a hose, and is used to mix the titanium alloy powder and the aluminum alloy powder to obtain an alloy mixed powder, and then feed the alloy mixed powder into the laser head through the hose. The spiral powder mixer 2 repeatedly stirs the titanium alloy powder and the aluminum alloy powder based on the spiral structure to make them uniformly mixed, avoiding the different flying speeds of the powders due to the density difference of titanium and aluminum alloy spheres with the same particle size, and further improving the uniformity of the alloy powder mixing.

[0054] The laser head 3 is used to move from the titanium alloy substrate side to the aluminum alloy substrate side according to the scanning set speed and place the alloy mixed powder in the molten pool, and to emit laser to the molten pool according to the laser set power and scanning set speed, and perform laser deposition operation on the molten pool to obtain a progressive interface of heterogeneous alloy materials. It should be noted that the mechanical arm controls the movement of the laser head 3 during the powder placement and laser deposition process, so that the laser head 3 moves according to the printing trajectory, and the spiral powder mixing agitator 2 does not move with the laser head 3.

[0055] The ultrasonic electromagnetic assisted laser additive manufacturing device is placed under the laser head 3, and is used to continuously use ultrasonic waves and electromagnetic fields to act on the molten pool during the laser deposition operation. During the laser additive manufacturing process, titanium atoms and aluminum atoms meet in the molten pool to form a coarse TiAl brittle phase, and due to the large difference in density between titanium alloy powder and aluminum alloy powder, there is a possibility of component segregation in the molten pool. Therefore, the ultrasonic wave can not only effectively promote the heat diffusion in the molten pool and reduce the temperature gradient in the molten pool, but also promote the uniform distribution of the TiAl brittle phase in the molten pool, avoid segregation, and fully crush the coarse TiAl brittle phase grains in the molten pool. Moreover, the DC electromagnetic field has a stirring effect on the molten pool of titanium alloy and aluminum alloy, effectively improving the uniformity of the TiAl brittle phase in the molten pool, and under the action of the DC electromagnetic field, the supercooling of the component at the front of the dendrite is effectively improved, and the growth rate of the TiAl brittle phase dendrite is slowed down, thereby promoting grain refinement. Therefore, the ultrasonic electromagnetic assisted laser additive manufacturing device can realize ultrasonic-electromagnetic multi-energy field coupling, and thus effectively guide the generation of fine and dispersed TiAl hard and brittle phases.

[0056] Specifically, the ultrasonic electromagnetic assisted laser additive manufacturing device includes an ultrasonic vibration system, a DC electromagnetic system and an ultrasonic vibration platform 4. It should be noted that the ultrasonic electromagnetic assisted laser additive manufacturing device uses a contact ultrasonic system and a DC electromagnetic field system as the basis of the entire device. In order to avoid interference from the external environment, the entire device is placed in a frame structure, which is a frame with a sealed cavity to ensure that the entire manufacturing process is always in an argon atmosphere.

[0057] The ultrasonic vibration system is placed on the ultrasonic vibration platform 4, which is used to generate ultrasonic waves, and uses ultrasonic waves to diffuse heat in the molten pool. The parameters of the ultrasonic vibration system are: ultrasonic vibration power is 100W, ultrasonic vibration current is 0.5A, and ultrasonic vibration frequency is 20.56kHz. Ultrasonic vibration is essentially the transmission of energy in the form of ultrasonic waves. The process of its transmission in liquid titanium alloy and aluminum alloy is also the process of energy transmission. Ultrasonic vibration can promote heat diffusion in the liquid molten pool of titanium alloy and aluminum alloy, reduce the temperature gradient in the molten pool, and improve the uniformity of the distribution of TiAl brittle phase in the molten pool. At the same time, it can fully crush the coarse grains in the TiAl phase without changing the phase composition in the organization, promote the refinement of the microstructure and the second phase of the alloy at the interface of the transition zone, and make the grain size and the second phase distribution more uniform.

[0058] The DC electromagnetic system is placed on the ultrasonic vibration platform 4, which is used to generate an electromagnetic field, and the electromagnetic field is used to stir the molten pool, wherein the parameters of the DC electromagnetic system are: the current is 400A, the voltage is 25V, and the electromagnetic field strength is 60mT. Since the external electromagnetic field has a stirring effect on the titanium alloy and aluminum alloy molten pools at the same time, the solidification behavior of the liquid metal in the molten pool changes, and the temperature field and solute field distribution of the molten pool also change. The complex physical and chemical phenomena such as the growth of TiAl phase dendrites, the formation of TiAl eutectic structure, and the segregation of Ti and Al elements accompanying the solidification process of liquid titanium alloy and aluminum alloy will also change. Increasing the electromagnetic field can improve the supercooling of the dendrite front component, slow down the growth rate of TiAl phase dendrites, and the violent convection effect on the molten pool can reduce the element segregation of titanium alloy and aluminum alloy, and promote the mutual dissolution and mixing of Ti and Al elements.

[0059] A processing platform 5 is provided on the upper surface of the ultrasonic vibration platform 4, and the processing platform 5 is used to place a titanium alloy substrate 6 and an aluminum alloy substrate 7 of a specific size and the same material as the workpiece to be additively manufactured. It should be noted that the ultrasonic vibration platform 4 is fixed in the middle of the frame structure, and the bottom of the ultrasonic vibration platform 4 is four supporting legs, the top is a platform, and the upper surface of the platform is provided with a processing platform 5.

[0060] Specifically, the ultrasonic vibration system includes an ultrasonic generator 8, an ultrasonic transducer 9 and an ultrasonic probe 10. The ultrasonic generator 8 is connected to four ultrasonic transducers 9 respectively, and is used to generate a high-frequency alternating current signal matching the ultrasonic transducer 9. Each ultrasonic transducer 9 is connected to an ultrasonic probe 10, which is used to convert the high-frequency alternating current signal into an ultrasonic wave, and the vibration direction of the ultrasonic wave is parallel to the axis direction of the four ultrasonic transducers 9. The ultrasonic probe 10 is used to transmit ultrasonic waves, and the four ultrasonic probes 10 are rigidly connected to a steel plate.

[0061] Specifically, the DC electromagnetic system includes a DC electromagnetic field generator, a power control cabinet and a water cooling system. The DC electromagnetic field generator is composed of a first water-cooled copper coil 11 and a second water-cooled copper coil 12, which are used to generate an electromagnetic field. The first water-cooled copper coil 11 and the second water-cooled copper coil 12 are placed opposite to each other on the ultrasonic vibration platform 4. The centers of the first water-cooled copper coil 11 and the second water-cooled copper coil 12 are on the same horizontal plane as the surface of the ultrasonic vibration platform 4, and the first water-cooled copper coil 11 and the second water-cooled copper coil 12 are slidably connected to the ultrasonic vibration platform 4. The power control cabinet is connected to the DC electromagnetic field generator, and is used to control the electromagnetic field induction intensity generated by the DC electromagnetic field generator by inputting current. The water cooling system is connected to the DC electromagnetic field generator, and is used to cool the DC electromagnetic field generator.

[0062] When preparing functional gradient materials based on laser melting deposition technology, the online real-time rapid and uniform mixing of multi-component metal powders remains a challenge. Traditional methods for preparing composite powders include V-type powder mixer mixing and planetary ball mill mixing. Although these methods can achieve mechanical mixing of metal powders, due to the differences in powder fluidity, density and surface energy unique to heterogeneous materials, the uniformity of the mixed powders and the gradual transition of the composition are still very limited. Especially in the case where online real-time mixing of the deposition process cannot be achieved, the required mixed powder composition ratio can only be prefabricated before the experiment, which significantly reduces the deposition efficiency of composition or performance gradient materials. Moreover, the chemical composition of the interface region is a gradient transition and there is an obvious interface composition mutation, which makes it impossible to achieve a gradual and smooth transition of the chemical composition from material 1 to material 2 in the interface transition zone.

[0063] Based on the above problems, the present application designs a double-barrel powder feeder 1, and the carrier gas flow rate of the powder feeder is 3.5L / min. The mass of titanium alloy powder and aluminum alloy powder to be delivered can be calculated online in real time by a computer, and the corresponding proportion of alloy powder can be adjusted online in real time. Specifically, the double-barrel powder feeder 1 includes a titanium alloy powder feeder and an aluminum alloy powder feeder. The titanium alloy powder feeder is connected to the spiral powder mixer 2 through a titanium alloy powder feeder tube, and is used to deliver titanium alloy powder according to the speed of the titanium alloy powder feeder. The aluminum alloy powder feeder is connected to the spiral powder mixer 2 through an aluminum alloy powder feeder tube, and is used to deliver aluminum alloy powder according to the speed of the aluminum alloy powder feeder, wherein the speed of the titanium alloy powder feeder and the speed of the aluminum alloy powder feeder are calculated according to the alloy powder ratio set in real time. The measurement unit of the double-barrel powder feeder 1 is r / min, that is, the quality of the delivered powder is regulated by setting the double-barrel powder feeder to rotate several times per minute. Due to the different densities of titanium alloy and aluminum alloy, the mass of powder delivered by the double-drum powder feeder per rotation is different. For example, the mass of titanium alloy powder delivered by the double-drum powder feeder per rotation is 2.52g, and the mass of aluminum alloy powder delivered is 1.39g. The molar mass is calculated based on the atomic weight of titanium element 47.867 and the atomic weight of aluminum element 26.9815386. It can be obtained that the molar mass ratio of titanium alloy and aluminum alloy powder delivered by the double-drum powder feeder per rotation is 1:1. During the movement of the laser along the scanning path, the rotation speed of the two powder feeding barrels of the double-barrel powder feeder is adjusted in real time to control the mass of the titanium alloy and aluminum alloy powders delivered. For example, if the molar mass ratio of the titanium alloy powder and the aluminum alloy powder to be delivered is 6.3:3.7, it is only necessary to adjust the titanium alloy powder feeding barrel to 0.63r / min and the aluminum alloy powder feeding barrel to 0.37r / min, and gradually transition from the titanium alloy substrate to the aluminum alloy substrate. The mass of the titanium alloy powder gradually decreases, and the mass of the aluminum alloy powder gradually increases, and a high-reliability progressive interface layer can be obtained.

[0064] Specifically, the spiral powder mixer 2 includes a cylindrical rod and a plurality of spiral blades axially arranged on the cylindrical rod. After the double-barrel powder feeder 1 blows the titanium alloy powder and the aluminum alloy powder into the spiral powder mixer 2, a large amount of powder flows through the first spiral blade and is cut into two parts, and reaches the second spiral blade. After multiple cycles, the titanium alloy powder and the aluminum alloy powder are evenly mixed, which can avoid the different flying speeds of the powders due to the difference in density of titanium and aluminum alloy spheres with the same particle size, and further improve the uniformity of the alloy powder mixing.

[0065] Specifically, the laser head 3 includes a laser powder feeding head and a laser. The laser powder feeding head is used to move from one side of the titanium alloy substrate to the side of the aluminum alloy substrate according to the scanning set speed and place the alloy mixed powder in the molten pool. The laser emits laser to the molten pool according to the laser setting power and the scanning setting speed, performs laser deposition operation on the molten pool, and obtains a progressive interface of heterogeneous alloy materials, wherein the laser scanning direction is parallel to the axial direction of the water-cooled copper coil, the laser power is 2000W, the scanning speed is 10mm / s, and the ultrasonic vibration system and the DC electromagnetic system are continuously turned on during the laser additive manufacturing process so that they act on the liquid molten pool all the time. The laser melting deposition technology is used to connect heterogeneous materials, which is suitable for the preparation of difficult-to-process metal materials, can improve the processing accuracy, and thus achieve the effect of near-net forming of complex parts, fine and uniform internal structure, and excellent mechanical properties.

[0066] The device provided in the embodiment of the present application includes a double-barrel powder feeder, a spiral powder mixer, a laser head, and an ultrasonic and electromagnetic-assisted laser additive manufacturing device: the double-barrel powder feeder is connected to the spiral powder mixer, and is used to feed titanium alloy powder and aluminum alloy powder to the spiral powder mixer according to the alloy powder ratio set in real time; the spiral powder mixer is connected to the laser head, and is used to mix the titanium alloy powder and the aluminum alloy powder to obtain an alloy mixed powder; the laser head is used to move from one side of the titanium alloy substrate to the other side of the aluminum alloy substrate according to a scanning set speed and place the alloy mixed powder in a molten pool, and to emit a laser to the molten pool according to a laser set power and a scanning set speed, perform a laser deposition operation on the molten pool, and obtain a progressive interface of a heterogeneous alloy material; the ultrasonic and electromagnetic-assisted laser additive manufacturing device is placed under the laser head, and is used to continuously use ultrasonic waves and electromagnetic fields to act on the molten pool during the laser deposition operation. This application adopts an ultrasonic electromagnetic assisted laser additive manufacturing device. Under the coupling effect of ultrasonic and electromagnetic fields on the stirring of the molten pool flow field and the braking effect, the uniformity of the mixing of the components in the transition zone of the heterogeneous materials is significantly improved, and the size and distribution uniformity of the grains and brittle second phases in the transition zone of the heterogeneous interface are reduced, thereby significantly improving the mechanical properties of the heterogeneous material connection zone. The use of a double-barrel powder feeder and a spiral powder mixer can avoid the problem of uneven mixing caused by the large density difference of the heterogeneous materials, and avoid the local poor fusion caused by component segregation. At the same time, it can also realize online real-time adjustment of the metal powder with a progressive mixing ratio, and avoid the problem of cracking caused by the gradual change step length of the mixed powder component with the interface component mutation. Based on this, a gradual transition of titanium alloy-transition interface-aluminum alloy components is formed, reducing the phase change stress level caused by the difference in the physicochemical properties of heterogeneous alloys and the interface component mutation, so that heterogeneous materials with large differences in physical parameters can be effectively connected, thereby realizing the integrated composite forming of heterogeneous alloys and large complex structural parts.

[0067] Further, as Figure 1The specific implementation of the device, the embodiment of the present application provides a control method for manufacturing a progressive interface of heterogeneous materials, such as Figure 2 As shown, the method includes:

[0068] 201. Fill argon gas into the sealed frame structure to which the titanium alloy substrate and the aluminum alloy substrate are fixed, start the ultrasonic vibration system according to the vibration setting parameters, and when it is detected that the vibration current and vibration frequency of the ultrasonic vibration system tend to be stable, start the DC electromagnetic system according to the electromagnetic setting parameters.

[0069] In an embodiment of the present application, a device for manufacturing a progressive interface of heterogeneous materials fills argon gas into a sealed frame structure fixed with a titanium alloy substrate and an aluminum alloy substrate. Next, the device for manufacturing a progressive interface of heterogeneous materials starts the ultrasonic vibration system according to the vibration setting parameters, and when it is detected that the vibration current and vibration frequency of the ultrasonic vibration system tend to be stable, the DC electromagnetic system is started according to the electromagnetic setting parameters. During the laser additive manufacturing process, the ultrasonic vibration system and the DC electromagnetic system may continue to act on the liquid molten pool, which is conducive to the formation of the primary TiAl brittle phase inside the fragmented molten pool and uniformly distribute it in the matrix, reduce the cracking tendency caused by the segregation of large-sized brittle phases at the interface, increase the effective bearing area of ​​the metal in the interface connection area, and disperse and strengthen the fine hard and brittle phases.

[0070] 202. The laser is controlled to emit laser according to the set laser power to form a molten pool at the connection between the titanium alloy substrate and the aluminum alloy substrate. The double-drum powder feeder is continuously controlled according to the real-time set alloy powder ratio to feed the titanium alloy powder and the aluminum alloy powder into the spiral powder mixer for mixing to obtain alloy mixed powder.

[0071] In the embodiment of the present application, the device for manufacturing a progressive interface of heterogeneous materials controls the laser to emit laser according to the laser setting power, and forms a molten pool at the connection between the titanium alloy substrate and the aluminum alloy substrate. Then, the device for manufacturing a progressive interface of heterogeneous materials continuously controls the double-barrel powder feeder according to the real-time set alloy powder ratio to feed the titanium alloy powder and the aluminum alloy powder into the spiral powder mixer for mixing to obtain an alloy mixed powder. The double-barrel powder feeder and the spiral powder mixer can avoid the problem of uneven mixing caused by the large density difference of heterogeneous materials, avoid the local poor fusion caused by component segregation, and at the same time, it can also realize online real-time adjustment of the metal powder conveying the progressive mixing ratio, and avoid the problem of cracking caused by the gradual change step of the mixed powder composition and the sudden change of the interface composition.

[0072] 203. Control the laser powder feeding head to move from the titanium alloy substrate side to the aluminum alloy substrate side and place the alloy mixed powder in the molten pool. During the movement from the titanium alloy substrate side to the aluminum alloy substrate side, the mass of the titanium alloy powder in the alloy mixed powder gradually decreases, and the mass of the aluminum alloy powder in the alloy mixed powder gradually increases.

[0073] In an embodiment of the present application, a device for manufacturing a progressive interface of heterogeneous materials controls a laser powder feeding head to move from one side of a titanium alloy substrate to one side of an aluminum alloy substrate and places an alloy mixed powder in a molten pool, wherein during the movement from one side of the titanium alloy substrate to one side of the aluminum alloy substrate, the mass of the titanium alloy powder in the alloy mixed powder gradually decreases, and the mass of the aluminum alloy powder in the alloy mixed powder gradually increases, thereby being able to generate a high-reliability progressive interface layer and achieve effective connection of heterogeneous materials with large differences in physical parameters.

[0074] 204. Control the laser to perform laser deposition operation on the molten pool containing the alloy mixed powder to obtain a progressive interface of heterogeneous materials. During the laser deposition operation, the ultrasonic vibration system continuously diffuses heat from the molten pool, and the DC electromagnetic system continuously stirs the molten pool.

[0075] In an embodiment of the present application, a device for manufacturing a progressive interface of heterogeneous materials controls a laser to perform laser deposition on a molten pool containing an alloy mixed powder to obtain a progressive interface of heterogeneous materials, wherein during the laser deposition operation, an ultrasonic vibration system continuously diffuses heat from the molten pool, and a DC electromagnetic system continuously stirs the molten pool. Under the coupling effect of ultrasonic vibration and electromagnetic field stirring of the molten pool flow field and braking effect, the uniformity of component mixing in the transition zone of the heterogeneous materials can be significantly improved, the size of grains and brittle second phases in the transition zone of the heterogeneous interface can be reduced, and the distribution uniformity of grains and brittle second phases can be improved, thereby significantly improving the mechanical properties of the connection zone of the heterogeneous materials.

[0076] The method provided in the embodiment of the present application adopts an ultrasonic electromagnetic assisted laser additive manufacturing device. Under the coupling effect of ultrasonic and electromagnetic fields on the stirring of the molten pool flow field and the braking effect, the uniformity of the mixing of the components in the transition zone of the heterogeneous materials is significantly improved, and the size and distribution uniformity of the grains and brittle second phases in the transition zone of the heterogeneous interface are reduced, thereby significantly improving the mechanical properties of the heterogeneous material connection zone. The use of a double-barrel powder feeder and a spiral powder mixer can avoid the problem of uneven mixing caused by the large density difference of the heterogeneous materials, and avoid the local poor fusion caused by component segregation. At the same time, it can also realize the online real-time adjustment of the metal powder conveying with a progressive mixing ratio, and avoid the problem of cracking caused by the interface component mutation due to the gradual change step length of the mixed powder component. Based on this, a gradual transition of titanium alloy-transition interface-aluminum alloy components is formed, the phase change stress level caused by the difference in the physicochemical properties of heterogeneous alloys and the interface component mutation is reduced, and the heterogeneous materials with large differences in physical parameters are effectively connected, thereby realizing the integrated composite forming of heterogeneous alloys and large complex structural parts.

[0077] Further, as a refinement and extension of the specific implementation of the above embodiment, in order to fully illustrate the specific implementation process of this embodiment, the embodiment of the present application provides another control method for manufacturing a progressive interface of heterogeneous materials, such as Figure 3A As shown, the method includes:

[0078] 301. Fill argon gas into the sealing frame structure to which the titanium alloy substrate and the aluminum alloy substrate are fixed.

[0079] In the embodiment of the present application, the substrates used are TC4 titanium alloy substrates and 7075 aluminum alloy substrates. The size of the substrates is 50mm×50mm×3mm, and a 45° groove is opened on one side of the substrate so that titanium and aluminum heterogeneous materials can be connected by laser melting deposition additive manufacturing technology. Since a layer of oxide film will form on the surface of the titanium alloy substrate and the aluminum alloy substrate when they are placed in the air for a long time, pretreatment is required before laser melting deposition. Specifically, the titanium alloy substrate and the aluminum alloy substrate are polished with 400-mesh metallographic sandpaper in advance to remove the oxide film on their surface until the metallic luster is exposed. Subsequently, 75% anhydrous ethanol reagent is used to wipe off the oil and dirt on the surface of the substrate, and hot air is blown dry for standby use. It should be noted that after the oxide film is removed, the heterogeneous materials should be connected within 2 hours to avoid the regeneration of a new oxide film. The pretreated titanium alloy substrate and aluminum alloy substrate are placed in the center of the processing platform, and the groove of the titanium alloy substrate is opposite to the groove of the aluminum alloy substrate, and the frame structure is sealed. Next, before the start of laser additive manufacturing, the argon gas is turned on and filled into the sealed frame structure with argon gas having a concentration of 99%, ensuring that the oxygen content in the sealed frame structure is below 50 ppm.

[0080] 302. Start the ultrasonic vibration system according to the vibration setting parameters. When it is detected that the vibration current and the vibration frequency of the ultrasonic vibration system tend to be stable, start the DC electromagnetic system according to the electromagnetic setting parameters.

[0081] In the embodiment of the present application, after the oxygen content in the frame structure is below 50ppm, the ultrasonic vibration system is turned on, and the ultrasonic vibration system parameters are adjusted, wherein the ultrasonic vibration power is 100W, the ultrasonic vibration current is 0.5A, and the ultrasonic vibration frequency is 20.56kHz. When the vibration current and vibration frequency of the ultrasonic vibration system tend to be stable, the DC electromagnetic system is turned on, and the DC electromagnetic system parameters are adjusted, wherein the current is 400A, the voltage is 25V, and the electromagnetic field strength is 60mT. It should be noted that the ultrasonic vibration auxiliary system and the DC electromagnetic system are continuously turned on during the laser additive manufacturing process so that they act on the liquid molten pool all the time. Ultrasonic vibration can promote the diffusion of heat in the liquid molten pool of titanium alloy and aluminum alloy, reduce the temperature gradient in the molten pool, and improve the uniformity of the distribution of the TiAl brittle phase in the molten pool. At the same time, the coarse grains in the TiAl phase can be fully broken up without changing the phase composition in the organization, and the microstructure and second phase of the alloy at the interface of the transition zone are further refined, and the grain size and second phase distribution are more uniform. The electromagnetic field can improve the supercooling of the dendrite front, slowing down the growth rate of TiAl phase dendrites, and the violent convection of the molten pool can reduce the element segregation of titanium alloy and aluminum alloy, and promote the mutual dissolution and mixing of Ti and Al elements. The combined effect of ultrasonic vibration and electromagnetic field can significantly improve the uniformity of component mixing in the transition zone of heterogeneous materials, reduce the size of grains and brittle second phases in the transition zone of heterogeneous interfaces, and improve the distribution uniformity of grains and brittle second phases, thereby significantly improving the mechanical properties of the heterogeneous material connection zone, and thus achieving effective connection of heterogeneous materials with large differences in physical parameters.

[0082] 303. Control the laser to emit laser according to the laser setting power, and form a molten pool at the connection between the titanium alloy substrate and the aluminum alloy substrate.

[0083] In the embodiment of the present application, the laser is controlled to emit laser according to the laser setting power, and a molten pool is formed at the connection between the titanium alloy substrate and the aluminum alloy substrate. The advantage of laser melting deposition technology is that it can flexibly change the composition of the conveyed powder during the manufacturing process, realize the rapid preparation of gradient material and composite material parts, and realize the integrated molding of part material-structure-function-performance.

[0084] 304. Adjust the rotation speed of the titanium alloy powder feeding barrel and the rotation speed of the aluminum alloy powder feeding barrel according to the alloy powder ratio at the current moment, so that the titanium alloy powder feeding barrel in the double-barrel powder feeder delivers titanium alloy powder according to the rotation speed of the titanium alloy powder feeding barrel, and the aluminum alloy powder feeding barrel in the double-barrel powder feeder delivers aluminum alloy powder according to the rotation speed of the aluminum alloy powder feeding barrel.

[0085] In the embodiment of the present application, TC4 titanium alloy powder and 7075 aluminum alloy powder are respectively placed in a double-barrel powder feeder, the double-barrel powder feeder is turned on, and the carrier gas flow rate of the powder feeder is adjusted to 3.5L / min. Then, the alloy powder ratio required at the current moment is calculated and controlled by a computer, and the speed of the titanium alloy powder feeder and the speed of the aluminum alloy powder feeder are adjusted according to the alloy powder ratio at the current moment, so that the titanium alloy powder feeder in the double-barrel powder feeder delivers titanium alloy powder according to the speed of the titanium alloy powder feeder, and the aluminum alloy powder feeder in the double-barrel powder feeder delivers aluminum alloy powder according to the speed of the aluminum alloy powder feeder, so as to realize online real-time precise control of heterogeneous alloy powders. Due to the different densities of titanium alloy and aluminum alloy, the mass of powder delivered by the double-drum powder feeder per rotation is different. For example, the mass of titanium alloy powder delivered by the double-drum powder feeder per rotation is 2.52g, and the mass of aluminum alloy powder delivered is 1.39g. The molar mass is calculated based on the atomic weight of titanium element 47.867 and the atomic weight of aluminum element 26.9815386. It can be obtained that the molar mass ratio of titanium alloy and aluminum alloy powder delivered by the double-drum powder feeder per rotation is 1:1. Therefore, according to the alloy powder ratio at the current moment, the rotation speed of the two powder feeding barrels of the double-drum powder feeder is adjusted in real time to control the mass of the titanium alloy and aluminum alloy powders delivered. For example, if the molar mass ratio of the titanium alloy powder and the aluminum alloy powder to be delivered is 6.3:3.7, it is only necessary to adjust the titanium alloy powder feeding barrel to 0.63r / min and the aluminum alloy powder feeding barrel to 0.37r / min, and gradually transition from the titanium alloy substrate to the aluminum alloy substrate. The mass of the titanium alloy powder gradually decreases, and the mass of the aluminum alloy powder gradually increases, so as to realize the design of a high-reliability progressive interface layer.

[0086] After the double-drum powder feeder feeds the titanium alloy powder and the aluminum alloy powder into the spiral powder mixer, the multiple spiral blades of the spiral powder mixer are used to divide the titanium alloy powder and the aluminum alloy powder for multiple times to obtain alloy mixed powder.

[0087] In the embodiment of the present application, the spiral powder mixer includes a series of spiral blades, each of which is connected by a cylindrical rod. After the double-barrel powder feeder blows the titanium alloy powder and the aluminum alloy powder into the spiral powder mixer, a large amount of powder flows through the first spiral blade and is cut into two parts, reaching the second spiral blade. After multiple cycles, the titanium alloy powder and the aluminum alloy powder are evenly mixed, which can avoid the different powder flight speeds due to the density difference of titanium and aluminum alloy spheres with the same particle size, and improve the uniformity of alloy powder mixing.

[0088] 306. Control the laser powder feeding head to move from the titanium alloy substrate side to the aluminum alloy substrate side and place the alloy mixed powder in the molten pool. During the movement from the titanium alloy substrate side to the aluminum alloy substrate side, the mass of the titanium alloy powder in the alloy mixed powder gradually decreases, and the mass of the aluminum alloy powder in the alloy mixed powder gradually increases.

[0089] In the embodiment of the present application, after the spiral powder mixer evenly stirs and delivers the alloy mixed powder, the scanning speed is adjusted to 10 mm / s, the laser powder feeding head is controlled to move from the titanium alloy substrate side to the aluminum alloy substrate side and the alloy mixed powder is placed in the molten pool, and the alloy mixed powder is evenly distributed in the molten pool under the action of ultrasonic waves and electromagnetic fields. Moreover, in the process of moving from the titanium alloy substrate side to the aluminum alloy substrate side, the mass of the titanium alloy powder in the alloy mixed powder gradually decreases, and the mass of the aluminum alloy powder in the alloy mixed powder gradually increases, that is, increasing the aluminum alloy powder feeding rate while reducing the titanium alloy powder feeding rate, which can reduce the composition mutation between adjacent step interfaces, and thus obtain a highly reliable progressive interface between titanium alloy and aluminum alloy.

[0090] 307. Control the laser to perform laser deposition operation on the molten pool containing the alloy mixed powder to obtain a progressive interface of heterogeneous materials. During the laser deposition operation, the ultrasonic vibration system continuously diffuses heat from the molten pool, and the DC electromagnetic system continuously stirs the molten pool.

[0091] In an embodiment of the present application, a laser is controlled to perform a laser deposition operation on a molten pool in which alloy mixed powder is placed, and a progressive interface of heterogeneous materials is obtained, wherein the laser scanning direction is parallel to the induction coil axis of the DC electromagnetic system, and the laser power is 2000W, and the scanning speed is 10mm / s. It should be noted that during the laser deposition operation, the ultrasonic vibration system continuously diffuses heat to the molten pool, and the DC electromagnetic system continuously stirs the molten pool. Since the connection of titanium alloy and aluminum alloy heterogeneous alloys will generate a large number of coarse-grained TiAl-based hard and brittle phases, in order to achieve the beneficial transformation of harmful phases, the present application adds an ultrasonic vibration system and a DC electromagnetic system as external field assistance. The external field assistance is based on the ultrasonic-electromagnetic multi-energy field coupling to guide the generation of fine and dispersed TiAl-based hard and brittle phases, which can improve the crystallization conditions of the alloy solidification process and improve the uniformity of the mixing of components in the transition zone of heterogeneous materials.

[0092] Based on the above process, the control method for manufacturing the progressive interface of heterogeneous materials proposed in this application can realize the effective connection of heterogeneous materials with large differences in physical parameters, and then realize the integrated composite forming of dissimilar alloys and large complex structural parts. Because the physical and chemical properties of titanium alloys and aluminum alloys are quite different, there is a large stress at the joint, and the interface reaction is prone to produce brittle intermetallic compounds. Therefore, this application reduces the phase change stress level caused by the difference in the physical and chemical properties of heterogeneous alloys and the sudden change of interface composition through the progressive transition of titanium alloy-transition interface-aluminum alloy composition.

[0093] In order to verify the beneficial effects of the device and control method for manufacturing a progressive interface of heterogeneous materials proposed in this application, the progressive interface of heterogeneous materials with high reliability after molding and the transition zone wire cutting obtained by conventional component gradient additive manufacturing were sampled to obtain progressive interface transition samples and gradient transition samples. They were then ground, polished and etched respectively, and observed with a metallographic microscope (OM, Optical Microscope), as shown in FIG. Figure 3B As shown, the gradient transition specimen manufactured by conventional composition gradient additive manufacturing has a clear transition interface, while the progressive gradient interface of the present application has no obvious transition interface and has better forming quality without defects such as cracks and pores.

[0094] Then, the hardness of the gradient transition and progressive transition was tested using a Vickers microhardness tester. Figure 3C As shown, the hardness of each layer of the gradient transition varies greatly, while the hardness of the progressive transition of the present application varies relatively smoothly, without sudden changes in the hardness value such as a sharp rise or fall.

[0095] Furthermore, the tensile strength of the composite component was tested using a universal tensile testing machine, such as Figure 3D As shown, the tensile strength of the gradient transition sample is 116MPa, and the elongation is 1.1%, indicating that the interface composition mutation effect and interface stress of the gradient transition have a significant impact on the bonding strength of the connection zone. The tensile strength of the progressive interface transition sample of the present application is 311MPa, and the elongation is 8.2%, indicating that the technical solution of multi-energy field assisted laser deposition to manufacture progressive interfaces proposed in the present application can improve the bonding strength of the transition zone interface and improve the service reliability of composite manufacturing components. It can be seen that the use of progressive transition for laser additive connection of titanium alloys and aluminum alloys is better, and a joint with good molding quality can be obtained, and the tensile strength can reach 311MPa.

[0096] Finally, the brittle phase distribution of the gradient transition TiAl system of titanium alloy and aluminum alloy is compared. Figure 3E As shown, the brittle phase growth and coarsening phenomenon of the gradient transition sample is obvious, while the progressive interface transition sample of the present application is a fine and dispersed TiAl hard and brittle phase, the TiAl brittle phase is evenly distributed, the coarse grains in the TiAl phase have been fully fragmented, and the grain size and the second phase distribution are more uniform, indicating that the mechanical properties of the heterogeneous material connection area are better.

[0097] The method provided in the embodiment of the present application adopts an ultrasonic electromagnetic assisted laser additive manufacturing device. Under the coupling effect of ultrasonic and electromagnetic fields on the stirring of the molten pool flow field and the braking effect, the uniformity of the mixing of the components in the transition zone of the heterogeneous materials is significantly improved, and the size and distribution uniformity of the grains and brittle second phases in the transition zone of the heterogeneous interface are reduced, thereby significantly improving the mechanical properties of the heterogeneous material connection zone. The use of a double-barrel powder feeder and a spiral powder mixer can avoid the problem of uneven mixing caused by the large density difference of the heterogeneous materials, and avoid the local poor fusion caused by component segregation. At the same time, it can also realize the online real-time adjustment of the metal powder conveying with a progressive mixing ratio, and avoid the problem of cracking caused by the interface component mutation due to the gradual change step length of the mixed powder component. Based on this, a gradual transition of titanium alloy-transition interface-aluminum alloy components is formed, the phase change stress level caused by the difference in the physicochemical properties of heterogeneous alloys and the interface component mutation is reduced, and the heterogeneous materials with large differences in physical parameters are effectively connected, thereby realizing the integrated composite forming of heterogeneous alloys and large complex structural parts.

[0098] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0099] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

[0100] Those skilled in the art will appreciate that the accompanying drawing is only a schematic diagram of a preferred implementation scenario, and the modules or processes in the accompanying drawing are not necessarily required for implementing the present application.

[0101] Those skilled in the art will appreciate that the modules in the device of the implementation scenario can be distributed in the device of the implementation scenario according to the implementation scenario description, or can be changed accordingly and located in one or more devices different from the implementation scenario. The modules of the above implementation scenario can be combined into one module, or can be further split into multiple sub-modules.

[0102] The above application serial numbers are for description only and do not represent the advantages or disadvantages of the implementation scenarios.

[0103] The above disclosure only discloses several specific implementation scenarios of the present application. However, the present application is not limited thereto, and any changes that can be conceived by technicians in this field should fall within the scope of protection of the present application.

Claims

1. A device for manufacturing a progressive interface of heterogeneous alloy materials, characterized in that: Including double-barrel powder feeder, spiral powder mixer, laser head, ultrasonic electromagnetic assisted laser additive manufacturing device: The double-barrel powder feeder is connected to the spiral powder mixer and is used to feed titanium alloy powder and aluminum alloy powder to the spiral powder mixer according to the alloy powder ratio set in real time; The spiral powder mixing agitator is connected to the laser head and is used to mix the titanium alloy powder and the aluminum alloy powder to obtain alloy mixed powder; The laser head is used to move from one side of the titanium alloy substrate to the side of the aluminum alloy substrate according to a scanning set speed and place the alloy mixed powder in a molten pool, and to emit laser to the molten pool according to a laser set power and the scanning set speed, perform laser deposition operation on the molten pool, and obtain a progressive interface of heterogeneous alloy materials; The ultrasonic electromagnetic assisted laser additive manufacturing device is placed under the laser head and is used to continuously use ultrasonic waves and electromagnetic fields to act on the molten pool during the laser deposition operation.

2. The device according to claim 1, characterized in that The ultrasonic electromagnetic assisted laser additive manufacturing device comprises an ultrasonic vibration system, a direct current electromagnetic system and an ultrasonic vibration platform: The ultrasonic vibration system is placed on the ultrasonic vibration platform and is used to generate the ultrasonic wave, and use the ultrasonic wave to diffuse heat from the molten pool; The DC electromagnetic system is placed on the ultrasonic vibration platform and is used to generate the electromagnetic field, and the molten pool is stirred by the electromagnetic field; A processing platform is arranged on the upper surface of the ultrasonic vibration platform, and the processing platform is used for placing the titanium alloy substrate and the aluminum alloy substrate.

3. The device according to claim 2, characterized in that The ultrasonic vibration system includes an ultrasonic generator, an ultrasonic transducer and an ultrasonic probe: The ultrasonic generator is connected to the four ultrasonic transducers respectively, and is used to generate a high-frequency alternating current signal matching the ultrasonic transducers; Each of the ultrasonic transducers is connected to an ultrasonic probe for converting the high-frequency alternating current signal into the ultrasonic wave, and the vibration direction of the ultrasonic wave is parallel to the axis direction of the four ultrasonic transducers; The ultrasonic probe is used to transmit the ultrasonic wave.

4. The device according to claim 2, characterized in that The DC electromagnetic system includes a DC electromagnetic field generator, a power control cabinet and a water cooling system: The DC electromagnetic field generator is composed of a first water-cooled copper coil and a second water-cooled copper coil, and is used to generate an electromagnetic field. The first water-cooled copper coil and the second water-cooled copper coil are placed opposite to each other on the ultrasonic vibration platform, and the first water-cooled copper coil and the second water-cooled copper coil are slidably connected to the ultrasonic vibration platform. The power control cabinet is connected to the DC electromagnetic field generator and is used to control the electromagnetic field induction intensity generated by the DC electromagnetic field generator through input current; The water cooling system is connected to the DC electromagnetic field generator and is used to cool the DC electromagnetic field generator.

5. The device according to claim 1, characterized in that The double-drum powder feeder comprises a titanium alloy powder feeder and an aluminum alloy powder feeder: The titanium alloy powder feeding cylinder is connected to the spiral powder mixing agitator through a titanium alloy powder feeding pipe, and is used to feed the titanium alloy powder according to the rotation speed of the titanium alloy powder feeding cylinder; The aluminum alloy powder feeding barrel is connected to the spiral powder mixing agitator through an aluminum alloy powder feeding tube, and is used to feed the aluminum alloy powder according to the rotation speed of the aluminum alloy powder feeding barrel, wherein the rotation speed of the titanium alloy powder feeding barrel and the rotation speed of the aluminum alloy powder feeding barrel are calculated based on the real-time set ratio of the alloy powders.

6. The device according to claim 1, characterized in that The spiral powder mixing agitator comprises a cylindrical rod and a plurality of spiral blades arranged on the cylindrical rod along the axial direction.

7. The device according to claim 1, characterized in that The laser head includes a laser powder feeding head and a laser: The laser powder feeding head is used to move from one side of the titanium alloy substrate to one side of the aluminum alloy substrate according to a scanning set speed and place the alloy mixed powder in the molten pool; The laser emits laser to the molten pool according to the laser setting power and the scanning setting speed, performs laser deposition operation on the molten pool, and obtains a progressive interface of heterogeneous alloy materials.

8. The device according to claim 1, characterized in that The device for manufacturing a progressive interface of heterogeneous alloy materials is operated under an argon atmosphere.

9. A control method for manufacturing a progressive interface of heterogeneous materials, characterized in that: The device for manufacturing a progressive interface of heterogeneous alloy materials as claimed in claim 1 comprises: Filling argon gas into a sealed frame structure to which a titanium alloy substrate and an aluminum alloy substrate are fixed, starting an ultrasonic vibration system according to vibration setting parameters, and when it is detected that the vibration current and vibration frequency of the ultrasonic vibration system tend to be stable, starting a DC electromagnetic system according to electromagnetic setting parameters; The laser is controlled to emit laser according to the laser setting power to form a molten pool at the connection between the titanium alloy substrate and the aluminum alloy substrate, and the double-barrel powder feeder is continuously controlled to feed the titanium alloy powder and the aluminum alloy powder into the spiral powder mixing stirrer for mixing according to the alloy powder ratio set in real time to obtain alloy mixed powder; Controlling the laser powder feeding head to move from the titanium alloy substrate side to the aluminum alloy substrate side and placing the alloy mixed powder in the molten pool, wherein during the movement from the titanium alloy substrate side to the aluminum alloy substrate side, the mass of the titanium alloy powder in the alloy mixed powder gradually decreases, and the mass of the aluminum alloy powder in the alloy mixed powder gradually increases; The laser is controlled to perform laser deposition on a molten pool containing the alloy mixed powder to obtain a progressive interface of heterogeneous materials, wherein during the laser deposition operation, the ultrasonic vibration system continuously diffuses heat from the molten pool and the DC electromagnetic system continuously stirs the molten pool.

10. The method according to claim 9, characterized in that The method of continuously controlling the double-drum powder feeder according to the alloy powder ratio set in real time to feed the titanium alloy powder and the aluminum alloy powder into the spiral powder mixing agitator for mixing to obtain the alloy mixed powder comprises: Obtaining the alloy powder ratio at the current moment, and adjusting the rotation speed of the titanium alloy powder feeding barrel and the rotation speed of the aluminum alloy powder feeding barrel according to the alloy powder ratio at the current moment, so that the titanium alloy powder feeding barrel in the double-barrel powder feeder delivers the titanium alloy powder at the rotation speed of the titanium alloy powder feeding barrel, and the aluminum alloy powder feeding barrel in the double-barrel powder feeder delivers the aluminum alloy powder at the rotation speed of the aluminum alloy powder feeding barrel; After the double-drum powder feeder feeds the titanium alloy powder and the aluminum alloy powder into the spiral powder mixer, the multiple spiral blades of the spiral powder mixer are used to divide the titanium alloy powder and the aluminum alloy powder multiple times to obtain the alloy mixed powder.

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