Method and device for regulating and controlling performance of laser cladding wear-resistant coating containing multiple strengthening phases

Abstract

The invention discloses a method and device for regulating and controlling the performance of a laser cladding wear-resistant coating containing multiple strengthening phases, and belongs to the technical field of laser cladding. The regulation and control method comprises the steps that the corresponding relation between the rotating speed and the powder feeding amount of each powder feeding unit is obtained, and the rotating speed of the powder feeding unit corresponding to each strengthening phase powder particle is regulated based on the preset powder feeding amount of each strengthening phase powder particle in the wear-resistant coating; the powder feeding gas flow is adjusted based on the density, the decomposability and the powder structure of each strengthening phase powder particle; the strengthening phase powder particles enter a powder feeding nozzle through a plurality of powder feeding units at the corresponding powder feeding air flow and are mixed at the outlet focus of the powder feeding nozzle; and the uniformly mixed strengthening phase powder particles are subjected to laser cladding, and the wear-resistant coating is prepared. According to the method and the device, the powder feeding gas flow of different types of powder is precisely regulated and controlled in a targeted manner, so that regulation and control of the structure and the performance of the high-hardness and high-wear-resistance cladding layer containing multiple strengthening phases are realized.

Description

Technical Field

[0001] The invention belongs to the technical field of laser cladding, and in particular relates to a method and a device for controlling the performance of a laser cladding wear-resistant coating containing multiple strengthening phases. Background Art

[0002] Laser cladding technology is a coating preparation method that adds the required cladding material to the surface of the substrate and uses a high-energy-density laser beam to irradiate it and melt it together with a thin layer on the surface of the substrate. Due to the low coating dilution rate (generally less than 5%), and the coating composition and dilution are controllable; it has a strong metallurgical bond or interface diffusion bond with the substrate; the heat input and distortion are small, especially when high-power density rapid cladding is used, the deformation can be reduced to the assembly tolerance of the parts; there is almost no restriction on the powder selection, especially when high-melting-point alloys are clad on the surface of low-melting-point metals; the thickness range of the cladding layer is large, and the coating thickness of a single powder feeding is 0.1-2.0mm; it can be selectively clad, with low material consumption and excellent performance-price ratio; beam aiming can enable cladding in inaccessible areas; the process is easy to automate; the cladding process is green and environmentally friendly, no noise and less dust, and many other advantages, the laser cladding process based on coaxial powder feeding has replaced traditional thermal spraying, electroplating, spray welding and other technologies, and has been widely used in the fields of metal parts repair, remanufacturing and surface modification.

[0003] Commonly used cladding powder materials include iron, cobalt, nickel and their alloys. Adding second phase particles to them to achieve the preparation of highly wear-resistant and corrosion-resistant protective layers is an important direction for laser cladding to prepare metal-based composite wear-resistant protective layers. According to the differences in the types and properties of the second phase, it can be divided into high-hardness metal carbides, such as tungsten carbide (WC), chromium carbide (Cr3C2), titanium carbide (TiC), etc., which have extremely high hardness and melting points, and serve as hard phases to improve the wear resistance of the cladding layer; metal sulfides (MoS2) or fluorides (CaF) with layered structures can reduce the friction coefficient of the cladding layer, thereby reducing wear and improving wear resistance; nano-titanium carbide (TiC) and vanadium carbide (VC) particles can increase wear resistance and refine grains to improve strength.

[0004] According to actual needs, a variety of powder materials with different properties and contents are added to form a composite reinforcement phase to meet the overall requirements of the metal-based composite wear-resistant layer in terms of wear resistance, erosion resistance, corrosion resistance, high temperature resistance, impact resistance, etc. under different working conditions. In addition, the powder feeding strategy is adjusted according to the performance and content of different powder particles, so as to regulate the structure and performance of the wear-resistant layer, which has become the main research direction of laser cladding to prepare wear-resistant protective layers.

[0005] However, the current preparation of metal-based composite powders for laser cladding mainly adopts the method of weighing the required amount of various powders according to the proportion, and then pre-mixing the composite powders by simple mechanical or manual stirring. The mixed powders are then sent into the molten pool through a powder feeding tube for cladding forming. Due to the differences in density, morphology and particle size of the metal matrix and various second-phase metal ceramic powder particles, it is difficult to ensure the stability of the composite powder content during mixing and transportation. In addition, high-density second-phase particles are easily deposited at the bottom of the cladding layer, and low-density second-phase particles are easy to float on the top of the cladding, which leads to uneven structure and performance of the cladding layer.

[0006] In addition, the melting point of the hard phase of metal ceramics currently used is extremely high, and it is difficult to use the traditional gas atomization powder making process to obtain spherical particles with good sphericity, good fluidity, internal density, and appropriate particle size. Most of them are irregular nanoparticles prepared by chemical methods, which cannot meet the powder feeding requirements of laser cladding. In order to solve the problem of powder delivery, high-energy ball mills are used for mechanical alloying, which is inefficient and costly; if nanoparticles are granulated and sintered, their internal density is difficult to ensure and pores are easily left.

[0007] Finally, the powder feeding gas flow rate has a significant impact on the temperature of the cladding layer and the speed and temperature of the powder particles during the cladding process, which in turn affects the structure and performance of the cladding layer. The current method for adjusting the powder feeding gas flow rate is relatively broad, and there is no strategy for setting different powder feeding gas flow rates for powder particles of different types, structures and morphologies, let alone adjusting the substrate temperature. Summary of the invention

[0008] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a method and device for regulating the performance of laser cladding wear-resistant coatings containing multiple reinforcing phases, by targeted and precise regulation of the powder feeding gas flow rate of different types of powders, so as to achieve the regulation of the structure and performance of high-hardness and high-wear-resistant cladding layers containing multiple reinforcing phases.

[0009] In order to achieve the above object, the present invention adopts the following technical solutions: The present invention provides a method for controlling the performance of a laser cladding wear-resistant coating containing multiple strengthening phases, comprising: Obtaining a corresponding relationship between the rotation speed and the powder feeding amount of the powder feeding unit, and adjusting the rotation speed of the powder feeding unit corresponding to each strengthening phase powder particle based on the preset powder feeding amount of each strengthening phase powder particle in the wear-resistant coating; Adjust the powder delivery gas flow rate based on the density, decomposability and powder structure of each strengthening phase powder particle; The powder particles of each strengthening phase are respectively fed into the powder feeding nozzle through a plurality of powder feeding units with corresponding powder feeding gas flow rates, and are mixed at the outlet focus of the powder feeding nozzle; The uniformly mixed powder particles of each reinforcement phase are subjected to laser cladding to obtain a wear-resistant coating.

[0010] Furthermore, the density of the powder particles is inversely proportional to the powder feeding gas flow rate.

[0011] Furthermore, the decomposability of the powder particles is directly proportional to the powder feeding gas flow rate.

[0012] Furthermore, the looseness of the powder structure is inversely proportional to the powder feeding gas flow rate.

[0013] Furthermore, the number and types of the reinforcing phase powder particles are consistent with the number of powder feeding units.

[0014] The present invention also provides a device for realizing the performance control method of the laser cladding wear-resistant coating containing multiple strengthening phases, comprising a multi-channel powder feeder and a powder feeding nozzle connected to the multi-channel powder feeder; the multi-channel powder feeder comprises a plurality of powder feeding units, and the powder feeding nozzle comprises a plurality of powder path channels; The powder delivery unit includes a powder delivery pipe, a powder delivery cylinder, a base and a powder delivery gas flow meter. The top of the powder delivery cylinder is connected to the powder delivery pipe, and the powder delivery cylinder is arranged above the base. The air outlet of the powder delivery gas flow meter is connected to the air inlet on the base; several powder outlets on the base are connected to the entrance of the powder path channel in a one-to-one correspondence.

[0015] Furthermore, the powder delivery nozzle also includes an optical path channel and a powder delivery nozzle body; The plurality of powder path channels are distributed in a circumferential manner inside the powder delivery nozzle body, the light path channel is arranged on the central axis of the powder delivery nozzle body, and the convergence focus of the plurality of powder path channels is coaxial with the light path channel.

[0016] Furthermore, the powder feeding nozzle body is in a conical shape.

[0017] Furthermore, the number of the powder feeding units is greater than 2.

[0018] Furthermore, the powder delivery amount of the powder delivery tube is 0.1-200 g / min, and the powder delivery accuracy is ±0.5%; the effective range of the powder delivery gas flow meter is 0.2-30 L / min, and the powder delivery accuracy is ±0.2%.

[0019] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a method for controlling the performance of a laser cladding wear-resistant coating containing multiple reinforcing phases, and controls the rotation speed of a powder feeding unit and the powder feeding airflow rate. Aiming at the problem of the stability of the composite powder content during powder mixing and transportation, the present invention is based on the preset powder feeding amount of each reinforcing phase powder particle in the wear-resistant coating, and can accurately adjust the rotation speed of the powder feeding unit corresponding to each reinforcing phase powder particle, thereby ensuring the ratio stability of various powders during mixing and transportation. By adjusting the powder feeding airflow rate of each reinforcing phase powder particle separately, and adjusting based on their density, decomposability, and powder structure, the sedimentation of high-density particles and the floating of low-density particles can be effectively avoided, thereby ensuring the uniformity of the structure and performance of the cladding layer.

[0020] In addition, in view of the preparation and delivery of metal ceramic hard phase powder, the present invention does not directly rely on the irregular nanoparticles prepared by the traditional gas atomization powder making process or chemical method, but adjusts the powder delivery gas flow rate and powder delivery method, so that even irregular or difficult to handle powders can be effectively used in the laser cladding process. By increasing the speed of dense particles to stir the molten pool, the granulated large-particle powder can be dispersed into small nanoparticles, thereby introducing nanomaterials into the cladding layer, which not only solves the problem of nanoparticle delivery, but also improves the overall performance of the cladding layer.

[0021] In response to the problem of the effect of powder feeding gas flow on the cladding layer, the present invention uses a strategy to adjust the powder feeding gas flow rate based on the characteristics of the powder particles (such as density, decomposability, structure, etc.), which can ensure that different types of powder particles have appropriate speed and temperature during the cladding process, thereby avoiding the dissolution and volatilization of the low-melting point additive phase and the decomposition of the agglomerated particles. By accurately controlling the overall powder feeding gas flow rate, not only can the cladding process be optimized, but also gas waste can be avoided and the overall efficiency can be improved.

[0022] The present invention also provides a laser cladding wear-resistant coating performance control device that realizes a laser cladding wear-resistant coating performance control method containing multiple reinforcing phases. Through multiple independent powder feeders, precise control and independent transportation of different powder materials are achieved. Each powder feeding unit is equipped with a separate powder feeding barrel, powder feeding tube and powder feeding gas flow meter. This configuration ensures the stability of the content of each powder during the mixing and transportation process, and effectively avoids the problem of uneven content caused by differences in powder density and morphology in traditional mixing methods. By independently adjusting the rotation speed and powder feeding gas flow of each powder feeding unit, uniform mixing and quantitative transportation of composite powders can be achieved, and each component can be accurately measured and evenly distributed in the cladding layer, thereby improving the overall performance of the cladding layer.

[0023] Furthermore, the present invention adopts a multi-channel independent powder feeding nozzle, the number of powder channel channels matches the type of powder or the powder feeding tube, and each powder channel is evenly distributed in the powder feeding nozzle in a conical shape, and the convergence focus is coaxial with the middle optical path. It not only solves the difficulty of mixing and conveying multiple second-phase particles, but also enables multiple powders to be accurately mixed at the front end of the powder feeding nozzle and smoothly fed into the molten pool. Since the high-speed dense particles can stir the molten pool, the dispersion of large-particle powder and the overflow of gas are promoted, which improves the density and uniformity of the cladding layer.

[0024] In addition, the multi-channel independent powder feeder can accurately control the powder feeding amount and speed of each powder, effectively avoiding the problems of powder agglomeration and blockage that may occur in the traditional conveying process. At the same time, the speed range of the powder feeding unit and the effective range of the powder feeding gas flow rate can be adjusted independently, avoiding the difficulties of mixing or alloying different powder particle densities and forms in the traditional way, and realizing low-cost, fast and uniform mixing and conveying of various material types and particle forms, which not only ensures the stable conveying of each strengthening phase powder particles and the laser cladding effect, but also reduces production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of a multi-channel powder feeder of the laser cladding wear-resistant coating performance control device of the present invention; Figure 2 It is a schematic structural diagram of a powder feeding nozzle of a laser cladding wear-resistant coating performance control device of the present invention; Figure 3 The present invention is a flow chart of a method for controlling the performance of a laser cladding wear-resistant coating containing multiple strengthening phases.

[0026] Among them: 1- multi-channel powder feeder; 2- powder feeding pipe; 3- powder feeding cylinder; 4- base; 5- powder feeding gas flow meter; 6- air inlet; 7- powder outlet; 8- powder path channel; 9- optical path channel; 10- powder feeding nozzle body. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0028] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0029] The present invention is further described in detail below in conjunction with the accompanying drawings: See also Figure 3 The present invention provides a method and device for regulating the performance of a laser cladding wear-resistant coating containing multiple strengthening phases. The method and device realize uniform mixing and quantitative transportation of powder particles of multiple types, structures and forms by independently feeding powders of different materials in multiple ways and controlling the independent powder feeding of each material. Different powder feeding strategies are then adopted for different powders, thereby achieving the purpose of regulating and adjusting the structure and performance of the laser cladding wear-resistant layer.

[0030] The above-mentioned method for controlling the performance of laser cladding wear-resistant coatings containing multiple strengthening phases can achieve uniform mixing and quantitative delivery of powder particles with different densities, different structures (dense, loose), and different morphologies, and can individually control the speed and temperature of different powder particles by adjusting the powder feeding gas flow rate, thereby effectively adjusting the composition distribution, pore structure and temperature of the cladding layer.

[0031] In the specific implementation process, a method for controlling the performance of a laser cladding wear-resistant coating containing multiple strengthening phases mainly includes the following contents: S1: Obtaining the corresponding relationship between the rotation speed and the powder feeding amount of the powder feeding unit, and adjusting the rotation speed of the powder feeding unit corresponding to each strengthening phase powder particle based on the preset powder feeding amount of each strengthening phase powder particle in the wear-resistant coating; S2: adjusting the powder feeding gas flow rate based on the density, decomposability and powder structure of each strengthening phase powder particle; S3: passing each strengthening phase powder particle through a plurality of powder feeding units with corresponding powder feeding gas flow rates into a powder feeding nozzle, and mixing at the outlet focus of the powder feeding nozzle; S4: Laser cladding is performed on the uniformly mixed powder particles of each reinforcement phase to obtain a wear-resistant coating.

[0032] Among them, the density of the powder particles is inversely proportional to the powder feeding gas flow rate, the decomposability of the powder particles is directly proportional to the powder feeding gas flow rate, the looseness of the powder structure is inversely proportional to the powder feeding gas flow rate, and the number of types of strengthening phase powder particles is consistent with the number of powder feeding units.

[0033] Using different flow rates for different powders can effectively adjust the speed and temperature of powder particles, effectively avoid the dissolution and volatilization of low-melting point additive phases, the sedimentation of high-density particles, and the decomposition of agglomerated particles, thereby ensuring stable performance; by adjusting the flow rate to increase the speed of dense particles, the molten pool can be stirred, and large granulated powder can be dispersed into small nanoparticles, thereby introducing nanomaterials into the cladding layer, improving the overall performance of the cladding layer, and promoting gas overflow and reducing porosity; the overall powder delivery gas flow rate can be accurately controlled to avoid gas waste.

[0034] The greater the density of the powder particles, the lower the powder delivery gas flow rate; the easier the powder particles are to decompose, the higher the powder delivery gas flow rate; the looser the powder particles are, the lower the powder delivery gas flow rate.

[0035] Among them, the multi-channel independent powder feeding strategy in S1 and S2 is adjusted as follows: The actual required powder particles of each strengthening phase are added into different powder feeding barrels 3. The powder feeding amount of different materials is tested by powder feeding, collection and weighing methods to obtain the corresponding relationship between the rotation speed and the powder feeding amount. The content of each material component is planned in advance according to the time, and the rotation speed of different powder feeding units is adjusted.

[0036] The speed and temperature of the powder particles can be controlled by adjusting the powder delivery gas flow rate. The specific strategies are as follows: For high-density strengthening phase powder particles (such as WC), a lower powder delivery gas flow rate can be used to reduce its velocity and avoid settling at the bottom of the cladding layer; For easily decomposable strengthening phase powders (such as MoS2), the powder delivery gas flow rate can be appropriately increased to avoid excessive heating of powder particles in the air and reduce the temperature; For nano-particle agglomerated granulation powder with loose interior (such as NrCr-CrC), a lower powder feeding gas flow rate can be used to increase its temperature and melting, so that it can be decomposed into finer particles; In addition, for strengthening phase powders with density comparable to that of the metal matrix and which are not easy to precipitate, a larger powder feeding gas flow rate can be used to increase its speed, stir the molten pool, promote uniform composition, and allow gas to overflow; and without affecting the quality of the cladding layer, one or several powder feeding gas flows can be appropriately adjusted to adjust the temperature of the matrix and cladding layer during the cladding process.

[0037] The cladding layer preparation process in S4 is as follows: According to the designed powder material type, the required cladding layer thickness and structure, the laser power, powder feeding amount, scanning speed, and overlap rate are matched and optimized to prepare the cladding layer. The cross-sectional metallographic method is used to observe the structure of the cladding layer, and the powder feeding gas flow rate is further adjusted to obtain the required cladding layer.

[0038] like Figure 1 and Figure 2 As shown, on one hand, the present invention provides a device for realizing the performance control method of the laser cladding wear-resistant coating containing multiple strengthening phases, which mainly includes a multi-channel powder feeder 1 and a powder feeding nozzle connected to the multi-channel powder feeder 1. A wide range high-precision powder feeder with multi-channel independent powder feeding function, a gas flow meter and a matching powder feeding nozzle are used. Various powders are mixed and melted outside the powder feeding nozzle, and each component is accurately measured and uniformly transported. The powder feeding gas flow rate can be adjusted separately, thereby ensuring the accuracy and uniformity of the content of each component of the final cladding layer.

[0039] Powder feeder capable of multi-channel powder feeding: The powder feeder required by the invention is as follows Figure 1 As shown, there are more than two powder feeding units that can independently control the powder feeding speed, and each powder feeding unit is equipped with a separate powder feeding tube 3, a powder feeding pipe 2 and a powder feeding gas flow meter 5. In order to meet the powder feeding requirements of different reinforcing phase contents, the powder feeding amount of a single powder feeding tube 3 meets 0.1-200g / min, the powder feeding accuracy is ±0.5%, and the effective range of the equipped powder feeding gas flow meter 5 is 0.2-30L / min and the powder feeding accuracy is ±0.2%.

[0040] Powder delivery nozzle capable of multi-channel powder delivery: The powder delivery nozzle structure used is as follows Figure 2 As shown, a coaxial powder feeding nozzle is used, which has the same number of powder channels as the type of powder or the powder feeding tube on the powder feeder, and the two are connected one by one. Several powder channels are evenly distributed in the powder feeding nozzle in a cone shape, and their convergence focus is coaxial with the middle light path.

[0041] Multi-channel independent powder feeding is used for mixing and conveying composite powders. According to the planned content ratio and the correspondence between different powders and powder feeder speeds measured in advance, the appropriate powder feeder speed and powder feeding amount are set. Several powder feeding tubes 2 are mixed at the focus of the powder feeding nozzle outlet of the cladding head and enter the molten pool for melting.

[0042] The multi-channel powder feeder 1 is a core component, which is composed of multiple independent powder feeding units, each of which is responsible for the storage and transportation of the corresponding powder. The powder feeding nozzle includes multiple powder channel 8 to form a one-to-one connection relationship with the powder feeding units in the multi-channel powder feeder 1. The number of powder feeding units is greater than 2, and the number of powder channel 8 is equal to the number of powder feeding units.

[0043] Each powder delivery unit is composed of a powder delivery pipe 2, a powder delivery cylinder 3, a base 4 and a powder delivery gas flow meter 5, wherein the top end of the powder delivery cylinder 3 is connected to the powder delivery pipe 2, the powder delivery cylinder 3 is installed on the mounting base 4, and the air outlet of the powder delivery gas flow meter 5 is connected to the air inlet 6 on the base 4; the powder outlets 7 on the multiple bases 4 correspond to and are connected to the entrances of the powder path 8 one by one.

[0044] The powder feeding nozzle is composed of a conical powder feeding nozzle body 10 and a powder path channel 8 and an optical path channel 9 therein; inside the powder feeding nozzle body 10, multiple powder path channels 8 are arranged in a surrounding manner, and the optical path channel 9 is located on the central axis of the powder feeding nozzle body 10, and the convergence points of all powder path channels 8 are coaxially aligned with the optical path channel 9.

[0045] The multi-channel powder feeder 1 is composed of a plurality of powder feeding units, each of which is equipped with an independent powder feeding cylinder 3 and a powder feeding gas flow meter 5. The rotation speed of the powder feeding cylinder 3 can be independently adjusted as needed, the rotation speed of the powder feeding cylinder 3 in several powder feeding units can be adjusted differently accordingly, and the powder feeding gas flow rates in several powder feeding units can be adjusted differently accordingly.

[0046] In a specific embodiment, a laser cladding wear-resistant coating performance control device is provided, which mainly includes the following contents, a powder feeder (multi-channel powder feeder 1) capable of multi-channel powder feeding and a powder feeding nozzle: Multi-channel powder feeder 1 Figure 1 As shown, there are more than two powder feeding units that can independently control the powder feeding speed, and each powder feeding unit is equipped with a separate powder feeding cylinder 3, a powder feeding pipe 2 and a powder feeding gas flow meter 5.

[0047] The powder delivery amount of the powder delivery tube 3 is 0.1-200g / min, and the powder delivery accuracy is ±0.5%; the effective range of the powder delivery gas flow meter 5 is 0.2-30L / min, and the powder delivery accuracy is ±0.2%.

[0048] The powder feeding nozzle can be used for multi-channel powder feeding. The structure of the powder feeding nozzle used is as follows Figure 2 As shown, a coaxial powder feeding nozzle is used, which has the same number of powder channels 8 as the type of powder or the powder feeding tubes 2 on the multi-channel powder feeder 1, and the two are connected one by one. Several powder channels 8 are evenly distributed in the powder feeding nozzle body 10 in a conical shape, and their convergence focus is coaxial with the middle light path (light path channel 9).

[0049] Multi-channel independent powder feeding is used for mixing and conveying composite powders. According to the planned content ratio and the correspondence between different powders and the rotation speed of the multi-channel powder feeder 1 measured in advance, the appropriate rotation speed and powder feeding amount of the multi-channel powder feeder 1 are set, and the powder is mixed at the front end of the powder feeding nozzle of the cladding head.

[0050] During the implementation process, the above-mentioned device can be used to adjust the independent powder feeding strategy containing multiple reinforcement phases. Specifically, the actually required powder is added to different powder feeding barrels 3, and the powder feeding amounts of different materials are first tested by the powder feeding, collection and weighing methods to obtain the corresponding relationship between the rotation speed of the powder feeding barrel 3 and the powder feeding amount; the content of each material component is planned in advance, and the rotation speed of different powder feeding units is adjusted; the powder feeding gas flow rate of each route is adjusted separately according to the actual situation, with the principle of being able to complete the stable transportation of each powder route, and it should not be too large or too small.

[0051] The multi-channel independent powder feeding laser cladding device and method achieves accurate mixing and conveying of a variety of different powder particles by independently regulating the rotation speed and powder feeding gas flow rate of the powder feeding unit.

[0052] In summary, the performance control method of the laser cladding wear-resistant coating containing multiple strengthening phases provided by the present invention adjusts the structure and performance of the cladding layer by adjusting the powder feeding strategy (powder feeder speed and powder feeding gas flow rate). The laser cladding wear-resistant coating performance control device can realize the independent conveying of multiple powder materials and includes a powder conveying system with a low-speed and high-precision powder feeder, a low-flow and high-precision gas flow meter and a corresponding powder feeding nozzle.

[0053] Example 1 A performance control method and device for laser cladding wear-resistant coating containing multiple strengthening phases are used to prepare wear-resistant coating on 40Cr substrate. The metal base material is 304 stainless steel spherical powder, the strengthening phase is spherical casting dense WC, granulated loose Cr3C2-20NiCr and TiC powders, wherein the WC content is 7wt%, the Cr3C2-20NiCr content is 16wt%, and the TiC content is 7 wt%. The laser power is 1400W, and the four powders are fed independently. The powder feeding gas flow rates are 5L / min, 1L / min, 1L / min, and 0.5L / min, respectively. The cladding speed is 0.04 m / s, the total powder feeding amount is 12g / min, and the overlap rate is 52%. The prepared composite cladding layer is dense inside without pores and cracks, has good bonding with the substrate, and the components are evenly distributed.

[0054] Example 2 A method and device for controlling the performance of laser cladding wear-resistant coatings containing multiple strengthening phases are used to prepare gradient wear-resistant coatings on gray cast iron substrates. The cladding layer material uses IN625 gas-atomized spherical powder as the matrix phase, and the strengthening phase is spherical casting dense WC, gas-atomized MoS2 and agglomerated granulated TiC powder, wherein the WC content is 20wt%, the MoS2 content is 10wt%, and the TiC content is 2wt%. The laser power is 4000W, and the four powders are fed independently. The feeding gas flow rates are 15L / min, 6L / min, 2L / min, and 1L / min, respectively. The cladding speed is 0.08 m / s, the total powder feeding amount is 110g / min, and the overlap rate is 60%. The prepared wear-resistant layer is dense and defect-free, and the components are evenly distributed, with a low friction coefficient and good wear resistance.

[0055] In summary, the present invention can achieve instant adjustment of the powder material content and rapid preparation of gradient structure cladding layers by adjusting the multi-channel independent powder feeding strategy. When the composition of the cladding layer needs to be changed, it is only necessary to simply adjust the rotation speed and powder feeding gas flow of each powder feeding unit without remixing the powder. This feature greatly improves production efficiency and flexibility. At the same time, the control device allows each powder to be independently controlled, realizing flexible use of powder and continuous control of cladding layer performance, further enhancing the flexibility of the cladding process, and meeting different requirements for workpiece surface performance under different working conditions.

[0056] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A method for controlling the performance of a laser cladding wear-resistant coating containing multiple strengthening phases, characterized in that: include: Obtaining a corresponding relationship between the rotation speed and the powder feeding amount of the powder feeding unit, and adjusting the rotation speed of the powder feeding unit corresponding to each strengthening phase powder particle based on the preset powder feeding amount of each strengthening phase powder particle in the wear-resistant coating; Adjust the powder delivery gas flow rate based on the density, decomposability and powder structure of each strengthening phase powder particle; The powder particles of each strengthening phase are respectively fed into the powder feeding nozzle through a plurality of powder feeding units with corresponding powder feeding gas flow rates, and are mixed at the outlet focus of the powder feeding nozzle; The uniformly mixed powder particles of each reinforcement phase are subjected to laser cladding to obtain a wear-resistant coating.

2. The method for controlling the performance of a laser cladding wear-resistant coating containing multiple strengthening phases according to claim 1, characterized in that: The density of the powder particles is inversely proportional to the powder feeding gas flow rate.

3. The method for controlling the performance of a laser cladding wear-resistant coating containing multiple strengthening phases according to claim 1, characterized in that: The decomposability of the powder particles is directly proportional to the powder feeding gas flow rate.

4. The method for controlling the performance of a laser cladding wear-resistant coating containing multiple strengthening phases according to claim 1, characterized in that: The looseness of the powder structure is inversely proportional to the powder delivery gas flow rate.

5. The method for controlling the performance of a laser cladding wear-resistant coating containing multiple strengthening phases according to claim 1, characterized in that: The types and quantity of the reinforcement phase powder particles are consistent with the number of the powder feeding units.

6. A laser cladding wear-resistant coating performance control device for realizing the laser cladding wear-resistant coating performance control method containing multiple strengthening phases as described in any one of claims 1 to 5, characterized in that: It comprises a multi-channel powder feeder (1) and a powder feeding nozzle connected to the multi-channel powder feeder (1); the multi-channel powder feeder (1) comprises a plurality of powder feeding units, and the powder feeding nozzle comprises a plurality of powder channel channels (8); The powder delivery unit comprises a powder delivery pipe (2), a powder delivery cylinder (3), a base (4) and a powder delivery gas flow meter (5); the top of the powder delivery cylinder (3) is connected to the powder delivery pipe (2); the powder delivery cylinder (3) is arranged above the base (4); the air outlet of the powder delivery gas flow meter (5) is connected to the air inlet (6) on the base (4); and a plurality of powder outlets (7) on the base (4) are connected to the inlet of the powder path (8) in a one-to-one correspondence.

7. The laser cladding wear-resistant coating performance control device according to claim 6, characterized in that: The powder delivery nozzle further comprises an optical path channel (9) and a powder delivery nozzle body (10); The plurality of powder path channels (8) are distributed in a circumferential manner inside the powder delivery nozzle body (10), the light path channel (9) is arranged on the central axis of the powder delivery nozzle body (10), and the convergence focus of the plurality of powder path channels (8) is coaxial with the light path channel (9).

8. The laser cladding wear-resistant coating performance control device according to claim 7, characterized in that: The powder delivery nozzle body (10) is in a conical shape.

9. The laser cladding wear-resistant coating performance control device according to claim 6, characterized in that: It is characterized in that The number of the powder feeding units is greater than 2.

10. The laser cladding wear-resistant coating performance control device according to claim 6, characterized in that: The powder delivery amount of the powder delivery tube (3) is 0.1-200 g / min, and the powder delivery accuracy is ±0.5%; the effective range of the powder delivery gas flow meter (5) is 0.2-30 L / min, and the powder delivery accuracy is ±0.2%.

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