A metal-based Ti-B-N ceramic particle reinforced gradient composite coating and a preparation method thereof

Abstract

This invention relates to a metal-based Ti-B-N ceramic particle-reinforced gradient composite coating and its preparation method, belonging to the fields of laser processing and metal metallurgy. It addresses the problems of existing metal-based ceramic materials with directly incorporated ceramic phases, which, when used in ultra-high-speed laser cladding, easily cause stress abrupt changes on both sides of the cladding interface, insufficient metallurgical bonding, and inadequate wear resistance in the shallow surface area of ​​the coating. The invention provides a metal-based Ti-B-N ceramic particle-reinforced gradient composite coating, wherein the composite coating comprises a Ti-B-N ceramic particle reinforcing phase, the reinforcing phase including TiN, TiB2, and a small amount of Ti4B2N3. This invention uses metal-based Ti-B-N ceramic particle powder to prepare the metal-based Ti-B-N ceramic particle-reinforced gradient composite coating in situ via ultra-high-speed laser cladding, which can alleviate stress abrupt changes at the interface and improve the shear strength and wear resistance of the substrate interface.

Description

Technical Field

[0001] This invention relates to the fields of laser processing and metal metallurgy, and in particular to a metal-based Ti-BN ceramic particle-reinforced gradient composite coating and its preparation method. Background Technology

[0002] Metal-based ceramic composite coatings directly incorporated into the ceramic phase combine the high temperature resistance and high hardness of ceramic materials with certain toughness and impact resistance. They are widely used in engineering machinery fields that require wear reduction, wear resistance, self-lubrication, corrosion resistance, fatigue resistance, and creep resistance. In particular, when manufacturing components such as drill pipes, drill bits, and hydraulic cylinder bodies, from the perspective of low-cost control of corrosion and wear resistance and service life extension, it is often necessary to repair the worn and failed surfaces by additive manufacturing a layer of metal-based ceramic coating. The preparation method usually adopts laser cladding.

[0003] Laser cladding technology is a surface modification process that involves adding cladding materials to the surface of a substrate using different filler methods. A high-power-density laser beam is then used to melt the cladding materials on the substrate surface, achieving eutectic melting with the substrate simultaneously. After rapid solidification, a dense cladding layer with good metallurgical bonding to the substrate is formed, thereby improving the substrate surface's wear resistance, corrosion resistance, heat resistance, or oxidation resistance. It has a wide range of applications and, compared with electroplating, features green and clean operation, high strength, and long lifespan.

[0004] Ultra-high-speed laser cladding is derived from laser cladding technology. It utilizes the convergence of spatial powder delivery and laser focusing to allow powder to converge at the laser focal point and melt instantaneously, then drip into the molten pool. This reduces the dilution rate to the substrate, significantly improving cladding efficiency, with cladding layers as thin as 0.2 mm. However, when metal-based ceramic materials with directly incorporated ceramic phases are used in ultra-high-speed laser cladding, the ceramic particles are prone to detaching from the metal matrix. The excessively low dilution rate and rapid cladding speed can also cause significant stress abrupt changes on both sides of the cladding interface, reducing the bonding strength of the metal-based ceramic composite coating / substrate interface and limiting the industrial expansion of ultra-high-speed laser cladding of metal-based ceramic composite coatings. Summary of the Invention

[0005] Based on the above analysis, the present invention aims to provide a metal-based Ti-BN ceramic particle-reinforced gradient composite coating and its preparation method, in order to at least solve one of the following problems existing in the ultra-high-speed laser cladding process of existing metal-based ceramic materials with directly incorporated ceramic phases: 1. Low dilution rate and fast cladding rate easily cause stress abrupt changes on both sides of the cladding interface, resulting in a mismatch of mechanical properties on both sides of the interface; 2. Insufficient metallurgical bonding at the cladding coating / substrate interface, leading to a high cracking rate at the cladding interface due to metallurgical defects; 3. Poor wettability between the externally introduced ceramic particle reinforcement phase and the coating metal matrix, resulting in significant particle phase peeling; 4. Agglomeration of directly incorporated ceramic phases in the metal-based ceramic composite coating, making it difficult to achieve a gradient dispersion distribution of ceramic particles in the vertical direction from the interface to the shallow surface, resulting in insufficient wear resistance or needing improvement in the shallow surface area of ​​the coating.

[0006] The objective of this invention is mainly achieved through the following technical solutions:

[0007] The present invention provides a metal-based Ti-BN ceramic particle reinforced gradient composite coating, the composite coating comprising a Ti-BN ceramic particle reinforcing phase, the reinforcing phase comprising TiN, TiB2 and a small amount of Ti4B2N3.

[0008] Furthermore, the content of the Ti-BN ceramic particle reinforcing phase is distributed in a gradient along the thickness direction of the composite coating.

[0009] Furthermore, the cladding interface width of the composite coating is 65-90 μm.

[0010] This invention also provides a method for preparing a metal-based Ti-BN ceramic particle-reinforced gradient composite coating, which includes the following steps:

[0011] S1: According to the composition design, spherical metal powder, non-spherical reduced Ti powder and sharded H-BN powder are mixed to obtain the original pre-alloyed mixed powder;

[0012] S2: The original pre-alloyed mixed powder is thoroughly mixed and dissociated by a closed turbine disc mechanical sand blowing and Ar ion beam dissociation to obtain mixed powder. The mixed powder is dried and then vacuum sealed for later use.

[0013] S3: Set the process parameters for ultra-high-speed laser cladding;

[0014] S4: Clamp the smooth and defect-free metal bar workpiece to be clad onto the laser cladding device, and adjust the laser spot and the powder spot to converge at a point in space, ensuring that the point is located 0.2mm-0.8mm above the starting cladding end of the workpiece.

[0015] S5: Using an ultra-high-speed laser cladding method, the mixed powder in S2 is clad onto the substrate surface to obtain a metal-based Ti-BN ceramic particle-reinforced gradient composite coating.

[0016] Further, in step S1, by mass percentage, the spherical metal powder: 70-80%, the non-spherical reduced Ti powder: 13.1-19.6%, and the flaky H-BN powder: 6.9-10.4%;

[0017] The spherical metal powder is metal-based, and the non-spherical reduced Ti powder and the fragmented H-BN powder are in-situ reactants.

[0018] Furthermore, in step S2, the Hall flow rate of the mixed powder is ≤35s / 50g.

[0019] Furthermore, in step S2, during the closed turbine disc mechanical sand blowing process, the screw rotation speed is ≥1r / s.

[0020] Furthermore, in step S2, during the Ar ion beam dissociation process, the Ar ion beam flow rate is ≥12L / min.

[0021] Furthermore, in step S2, the interaction time of the sealed turbine disc mechanical sand blowing and Ar ion beam dissociation is ≥1h.

[0022] Further, in step S3, the process parameters for the ultra-high-speed laser cladding are: laser power 1600-1800W, workpiece outer diameter rotational linear speed 21-23m / min, cladding head axial movement speed 0.3-0.35mm / r, powder carrier gas flow rate 7-9L / min, protective gas flow rate 6-7L / min, and powder feeding rate 34-36g / min.

[0023] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0024] 1. This invention relates to a metal-based Ti-BN ceramic particle powder for in-situ preparation of a metal-based Ti-BN ceramic particle-reinforced gradient composite coating using ultra-high-speed laser cladding. The powder comprises a low-C, Ni- and Fe-containing metal "soft" coating material with excellent compatibility with the substrate steel, pure metallic titanium (Ti), and H-type cubic boron nitride (H-BN). During the high-speed cladding of the "soft" coating on the surface of a rotating shaft-type steel workpiece, the in-situ synthesis and preparation of the self-generated Ti-BN ceramic hard phase inside the coating can be achieved simultaneously. A certain stress gradient change is formed at the cladding interface, thereby alleviating the stress abrupt change at the interface. At the same time, a gradient distribution of the self-generated Ti-BN ceramic particle reinforcing phase is achieved in the vertical direction of the composite coating.

[0025] 2. This invention relates to the in-situ preparation of a metal-based Ti-BN ceramic particle reinforced gradient composite coating using ultra-high-speed laser cladding. After restoring fluidity, the powder achieves a Hall flow rate of ≤35s / 50g. Subsequently, through ultra-high-speed laser cladding technology in the additive manufacturing of rotating shaft parts, the cladding interface width of this composite coating is increased by more than 1 times compared to the interface width of a metal-based cladding coating directly incorporating ceramic phases under the same process. Simultaneously, the in-situ synthesis and self-generation of the Ti-BN ceramic particle reinforcing phase in the metal-based Ti-BN ceramic particle composite coating of this invention are achieved. Under the action of high-speed rotational centrifugal force, the content gradient of the self-generated Ti-BN ceramic particle reinforcing phase changes along the vertical direction (coating thickness direction) of the composite coating without particle agglomeration effect. The volume percentage of the in-situ self-generated Ti-BN ceramic particle reinforcing phase within the shallow position (within 100μm) of the composite coating is not less than 40%, and the wear resistance is reduced by more than half compared to the wear weight loss of Cr12MoV cold work die steel.

[0026] 3. This invention prepares a metal-based Ti-BN ceramic particle-reinforced gradient composite coating in situ by ultra-high-speed laser cladding using metal-based Ti-BN ceramic particle powder. Compared with metal-based ceramic composite coatings that are directly mixed into the ceramic phase, the shear strength of the matrix interface is increased by more than 50%.

[0027] 4. The present invention provides a metal-based Ti-BN ceramic particle-reinforced gradient composite coating prepared in situ by ultra-high-speed laser cladding using metal-based Ti-BN ceramic particle powder, which reduces porosity and cracks to below 3.5%.

[0028] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained from what is particularly pointed out in the description and drawings. Attached Figure Description

[0029] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0030] Figure 1 This is the cladding interface of the metal-based Ti-BN ceramic particle-reinforced gradient composite coating in Example 1 of the present invention;

[0031] Figure 2 This is the cladding interface of the metal-based coating in Comparative Example 6 of the present invention;

[0032] Figure 3The morphology and wear characteristics of the composite ceramic particles at the shallow position of the metal-based Ti-BN ceramic particle-reinforced gradient composite coating in Embodiment 1 of the present invention.

[0033] Figure 4 This is the morphology of composite ceramic particles near the interface (closer to the coating side) of the metal-based Ti-BN ceramic particle-reinforced gradient composite coating in Example 1 of the present invention.

[0034] Figure 5 The surface of Cr12MoV cold work die steel material is at a shallow position of the metal-based Ti-BN ceramic particle reinforced gradient composite coating of Example 1 of this invention. Figure 3 (As shown) Wear morphology under the same wear conditions;

[0035] Figure 6 The macroscopic interface defects of the cladding interface of the metal-based coating in Comparative Example 6 of the present invention are shown.

[0036] Figure 7 This is a schematic diagram of the ultra-high-speed laser cladding process of metal-based Ti-BN ceramic particles and powder according to the present invention;

[0037] Figure 8 This is a schematic diagram showing the convergence of the laser beam and the powder spot in the annular cone during the ultra-high-speed laser cladding process of metal-based Ti-BN ceramic particles in this invention.

[0038] Figure 9 This is a comparison of the stress distribution at the cladding interface of the metal-based Ti-BN ceramic particle-reinforced gradient composite coating in Example 1 and the cladding interface in Comparative Example 6. Detailed Implementation

[0039] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0040] This invention provides a method for preparing a metal-based Ti-BN ceramic particle-reinforced gradient composite coating, comprising the following steps:

[0041] S1: According to the composition design, metal spherical powder, non-spherical reduced Ti powder and sharded H-BN powder are mixed to obtain the original pre-alloyed mixed powder;

[0042] S2: The original pre-alloyed mixed powder is thoroughly mixed and dissociated by a closed turbine disc mechanical sand blowing and Ar ion beam dissociation to obtain mixed powder. The mixed powder is dried and then vacuum sealed for later use.

[0043] S3: Set the process parameters for ultra-high-speed laser cladding;

[0044] S4: Clamp the smooth and defect-free metal bar workpiece to be clad onto the laser cladding device, and adjust the laser spot and the powder spot to converge at a point in space, ensuring that the point is located 0.2mm-0.8mm above the starting cladding end of the workpiece.

[0045] S5: Using an ultra-high-speed laser cladding method, the mixed powder in S2 is clad onto the substrate surface to obtain a metal-based Ti-BN ceramic particle-reinforced gradient composite coating.

[0046] Specifically, in step S1, the original pre-alloyed mixed powder is a metal-based Ti-BN ceramic particle powder for ultra-high-speed laser cladding, containing the following components in the following mass percentages: spherical metal powder: 70-80%, non-spherical reduced Ti powder: 13.1-19.6%, and sharded H-BN powder: 6.9-10.4%.

[0047] The spherical metal powder is one of Fe-based stainless steel or Ni-based high-temperature alloy powder materials; the sphericity is ≥95%, the particle size distribution is 15-53μm, and the flowability is ≤25s / 50g.

[0048] The non-spherical reduced Ti powder has a particle size distribution of 5-20 μm.

[0049] The fragmented H-BN powder has a particle size distribution of 3-5 μm.

[0050] The spherical metal powder serves as the metal matrix, while the non-spherical reduced Ti powder and the fragmented H-BN powder serve as in-situ reactants.

[0051] Specifically, in step S2, the original pre-alloyed mixed powder is loaded into a sealed device that is circulated with Ar gas. After the oxygen content in the device environment is lower than 1%, the turbine disk rotation mode is turned on. The disk rotates with the screw at a speed of ≥1r / s, which drives the original pre-alloyed mixed powder below the device to rise, so as to achieve the purpose of uniform powder mixing. At the same time, some powder can achieve temporary spatial dispersion in the sealed space of the device. When the turbine disk speed is lower than 1r / s, there is less spatially dispersed powder, which affects the subsequent Ar ion beam dissociation effect.

[0052] As the turbine disk rotates within the device, annular Ar ion beam nozzles are arranged on the inner wall of the top of the device, with an Ar ion beam flow rate of not less than 12 L / min. When the turbine disk mixes the original powder, the mutual friction between the powder particles easily generates charges, leading to electrostatic attraction and agglomeration. Therefore, Ar ion beam nozzles are arranged on the inner wall of the top of the device to continuously inject positively and negatively charged ion gas, randomly neutralizing it with the spatially dispersed powder to prevent agglomeration due to powder friction and electrostatic attraction. This ensures that the mixed powder achieves a certain degree of powder flowability after mechanical sand-throwing mixing in a closed turbine disk and Ar ion beam dissociation, with a Hall flow rate ≤ 35 s / 50 g; the mixing and dissociation time is ≥ 1 h. An Ar ion beam flow rate lower than 12 L / min affects the spatial dissociation effect of the powder. Through steps S1 and S2, the metal-based Ti-BN ceramic particle powder regains its flowability.

[0053] Specifically, in step S3, the process parameters for ultra-high-speed laser cladding are: laser power 1600-1800W, workpiece outer diameter rotational linear speed 21-23m / min, cladding head axial movement speed 0.3-0.35mm / r, powder carrier gas flow rate 7-9L / min, protective gas flow rate 6-7L / min, and powder feeding rate 34-36g / min.

[0054] Specifically, in step S4, the light spot refers to the laser focus, and the powder spot refers to the metal-based Ti-BN ceramic particles, such as... Figure 7 The annular cone powder feeding point is shown, and this point is ensured to be located 0.2mm-0.8mm above the starting cladding end of the workpiece. This allows the metal-based Ti-BN ceramic particles to melt at the intersection of the light spot and the powder spot, and then drop into the molten pool on the surface of the substrate in the form of droplets to bond with the substrate.

[0055] Specifically, in step S4, the metal-based Ti-BN ceramic particles undergo an in-situ reaction during heating at the powder spot-light spot co-focal location and as they enter the molten pool. During this process, Ti reacts with elements such as Fe, Ni, C, and B in the H-BN and metal spherical powders as follows:

[0056] Ti (固) + Ni (固) → NiTi (液) (1)

[0057] Ti (固) + Fe (固) → α-Fe (Ti) (2)

[0058] Ti + C → TiC + Q (3)

[0059] Ti + 2B → TiB2 + Q (4)

[0060] 6Ti + 4BN → TiN + TiB2 + Ti4B2N3 + Q (5)

[0061] Among them, the theoretical calculated values ​​of Gibbs free energy ΔG of equations (3), (4) and (5) at 1500K are approximately -200kJ / mol, -270kJ / mol and -690kJ / mol, respectively, and all are exothermic reactions. Therefore, under the condition of the lowest ΔG, the reaction of equation (5) can preferentially generate TiN+TiB2+Ti4B2N3, and compensate for a large amount of Joule heat under the rapid cooling and heat dissipation conditions of the molten pool of ultra-high speed laser cladding, prolong the high temperature residence time of the molten pool, reduce the cooling rate, and provide transient temperature guarantee for the full progress of the reaction. As the reaction proceeds, the Ti content in equations (1) and (2) decreases, and the Ni, Fe, C, B and other elements introduced by the original metal spherical powder are retained in the metal matrix of the coating in the form of solid solution. Based on the above principles, when the Ti content exceeds the range described in this invention, after completing the reaction of formula (5), the reactions of formula (3) and formula (4) will continue to be induced in the molten pool under laser action, that is, reacting with C and B in the metal spherical powder, which will reduce the hardness of the coating metal matrix and is not conducive to improving the wear resistance of the composite coating formed by laser cladding; when the Ti powder content is low, the relative H-BN powder content is high, which may lead to poor wettability between H-BN powder and coating metal matrix, and the wear and peeling of residual H-BN powder particles is likely to occur during the subsequent coating wear process, resulting in rapid weight loss of the coating.

[0062] This invention also provides a metal-based Ti-BN ceramic particle-reinforced gradient composite coating, obtained by the above-described preparation method. The reinforcing phase of the metal-based Ti-BN ceramic particle-reinforced gradient composite coating is an in-situ generated product, comprising TiN, TiB2, and a small amount of Ti4B2N3. Due to the significant difference in density between the reinforcing phase and the metal matrix, during the cladding process on the workpiece surface, under the centrifugal force of the high-speed rotation of the workpiece, the content of the Ti-BN ceramic particle reinforcing phase exhibits a gradient distribution along the vertical direction (coating thickness direction) of the composite coating. The volume percentage of the in-situ self-generated composite ceramic particle reinforcing phase in the shallow surface position (within 100 μm) of the composite coating is not less than 40%. The cladding interface width of the metal-based Ti-BN ceramic particle-reinforced gradient composite coating reaches 65-90 μm, which is more than twice the interface width (5-10 μm) of the metal-based cladding coating under the same process. Figure 3 This invention relates to the morphology and wear characteristics of composite ceramic particles at shallow locations of a metal-based Ti-BN ceramic particle-reinforced gradient composite coating, as shown in this embodiment. Figure 4The near-interface position (closer to the coating side) of the metal-based Ti-BN ceramic particle-reinforced gradient composite coating in this embodiment of the invention clearly shows that the volume percentage of the Ti-BN ceramic particle reinforcing phase varies along the vertical direction (coating thickness direction) of the composite coating. Figure 7 As shown, under the action of centrifugal force, the Ti-BN ceramic particle reinforcement phase generated in situ in the laser molten pool of the cladding workpiece exhibits a natural gradient distribution along the vertical direction (coating thickness direction) of the composite coating.

[0063] This invention abandons the selection of high-C, high-Mo, high-Cr, and high-W high-wear-resistant coating materials that are prone to cladding cracking. Instead, it selects a low-C, Ni- and Fe-containing metallic "soft" coating material with excellent compatibility with the base steel. Combined with a specific ratio of pure titanium (Ti) and H-type cubic boron nitride (H-BN), it enables the in-situ synthesis and preparation of self-generated Ti-BN ceramic particle reinforcement phases within the coating during the high-speed cladding of the metallic "soft" coating onto the surface of a rotating shaft-type steel workpiece. Furthermore, during the cladding process, the cladding interface between the "soft" coating and the rotating shaft-type steel workpiece is compensated for by the Joule heating within the molten pool, reducing the rate of temperature drop. This, coupled with a decrease in the difference in hardness between the coating substrate and the workpiece at room temperature, alleviates the stress abrupt change between the coating, interface, and workpiece. Figure 9 As shown, a gradient distribution of self-generated Ti-BN ceramic particle reinforcement phase is simultaneously achieved in the vertical direction of the coating.

[0064] The metal-based Ti-BN ceramic particle reinforced gradient composite coating of this invention achieves a Hall flow rate of ≤35s / 50g when the particle size is ≤53μm. Subsequently, in the additive cladding manufacturing of rotating shaft workpieces using ultra-high speed laser cladding technology, the cladding interface width of the composite coating can be increased by more than 1 times compared with the interface width of metal-based cladding coatings directly mixed with ceramic phase under the same cladding process. At the same time, the in-situ synthesis of the Ti-BN ceramic particle reinforcing phase in the composite coating is achieved. The content gradient of the self-generated Ti-BN ceramic particle reinforcing phase changes along the vertical direction (coating thickness direction) of the composite coating under the action of high-speed rotation centrifugal force. The volume percentage of the in-situ self-generated Ti-BN ceramic particle reinforcing phase within the shallow position (within 100μm) of the composite coating is not less than 40%, and the wear resistance is reduced by more than half compared with the wear resistance weight loss of Cr12MoV cold work die steel.

[0065] Example 1

[0066] The metal-based Ti-BN ceramic particle powder of this embodiment contains the following components in the following mass percentages: 431 stainless steel spherical powder: 80%, non-spherical reduced Ti powder: 13.1%, and flaky H-BN powder: 6.9%.

[0067] The sphericity of the 431 stainless steel spherical powder is 96%, the particle size distribution is 15-53μm, and the Hall flow rate is 18s / 50g.

[0068] The non-spherical reduced Ti powder has a particle size distribution of 5-20 μm.

[0069] The fragmented H-BN powder has a particle size distribution of 3-5 μm.

[0070] The spherical metal powder serves as the metal matrix, while the non-spherical reduced Ti powder and the fragmented H-BN powder serve as in-situ reactants.

[0071] The original pre-alloyed mixed powder was thoroughly mixed and dissociated by a closed turbine disc mechanical sand blowing and Ar ion beam dissociation to obtain the final mixed powder. The screw rotation speed was 1 r / s, the Ar ion beam flow rate was 12 L / min, and the mixing and dissociation time was 1 h. The final mixed powder had a Hall flow rate of 20 s / 50 g.

[0072] The final mixed powder was clad onto the substrate surface using an ultra-high-speed laser cladding method to obtain a metal-based Ti-BN ceramic particle-reinforced gradient composite coating.

[0073] The laser power is 1700W, the workpiece outer diameter rotational linear speed is 22m / min, the axial movement speed of the cladding head is 0.33mm / r, the powder-carrying gas flow rate is 8L / min, the protective gas flow rate is 6.6L / min, and the powder feeding rate is 35g / min.

[0074] The cladding interface of the composite coating is 70-75 μm wide, with a porosity and crack defect rate of 0.3% and an interfacial shear strength of 550 MPa. The shallow surface layer of this composite coating was tested for wear resistance according to the "GT / T 12444-2006 Metallic Materials Wear Test Method: Ring-Block Sliding Wear Test". The wear weight loss was 9 mg / h, and the volume percentage of in-situ self-generated Ti-BN ceramic particle reinforcement phase within 100 μm of the shallow surface of the composite coating was 40-45%. The cladding interface of the metal-based Ti-BN ceramic particle reinforced gradient composite coating in this embodiment is as follows: Figure 1 As shown.

[0075] Example 1-1

[0076] The composition and ratio of the metal-based Ti-BN ceramic particles in this embodiment are the same as those in Example 1. The closed turbine disk mechanical sand blowing, Ar ion beam dissociation, and ultra-high speed laser cladding processes are the same. The difference is that the Hall flow rate of the metal-based Ti-BN ceramic particles is 22s / 50g, and the screw rotation speed is 2r / s.

[0077] The laser power is 1700W, the workpiece outer diameter rotational linear speed is 22m / min, the axial movement speed of the cladding head is 0.33mm / r, the powder-carrying gas flow rate is 8L / min, the protective gas flow rate is 6.6L / min, and the powder feeding rate is 35g / min.

[0078] The composite coating after cladding has an interface width of 68-76 μm, a porosity and crack defect rate of 0.3%, and an interface shear strength of 570 MPa. The shallow surface layer of this composite coating was tested for wear resistance according to the "GT / T 12444-2006 Metallic Materials Wear Test Method: Ring-Block Sliding Wear Test". The wear weight loss was 8 mg / h, and the volume percentage of in-situ self-generated Ti-BN ceramic particles reinforcing phase within 100 μm of the shallow surface of the composite coating was 40-45%.

[0079] Examples 1-2

[0080] The composition and ratio of the metal-based Ti-BN ceramic particles in this embodiment are the same as those in Example 1. The closed turbine disk mechanical sand blowing, Ar ion beam dissociation, and ultra-high speed laser cladding processes are the same. The difference is that the Hall flow rate of the metal-based Ti-BN ceramic particles is 23s / 50g, and the Ar ion beam flow rate is 15L / min.

[0081] The laser power is 1700W, the workpiece outer diameter rotational linear speed is 22m / min, the axial movement speed of the cladding head is 0.33mm / r, the powder-carrying gas flow rate is 8L / min, the protective gas flow rate is 6.6L / min, and the powder feeding rate is 35g / min.

[0082] The composite coating after cladding has an interface width of 65-74 μm, a porosity and crack defect rate of 0.32%, and an interface shear strength of 540 MPa. The shallow surface layer of this composite coating was tested for wear resistance according to the "GT / T 12444-2006 Metallic Materials Wear Test Method: Ring-Block Sliding Wear Test". The wear weight loss was 8 mg / h, and the volume percentage of in-situ self-generated Ti-BN ceramic particles reinforcing phase within 100 μm of the shallow surface of the composite coating was 40-45%.

[0083] Example 2

[0084] The metal-based Ti-BN ceramic particle powder of this embodiment contains the following components in the following mass percentages: 431 stainless steel spherical powder: 75%, non-spherical reduced Ti powder: 16.35%, and flaky H-BN powder: 8.65%.

[0085] The spherical powder of the 431 martensitic stainless steel has a sphericity of 96%, a particle size of 15-53 μm, and a Hall flow rate of 18 s / 50 g.

[0086] The non-spherical reduced Ti powder has a particle size distribution of 5-20 μm.

[0087] The fragmented H-BN powder has a particle size distribution of 3-5 μm.

[0088] The spherical metal powder serves as the metal matrix, while the non-spherical reduced Ti powder and the fragmented H-BN powder serve as in-situ reactants.

[0089] The original pre-alloyed mixed powder was thoroughly mixed and dissociated by a closed turbine disc mechanical sand blowing and Ar ion beam dissociation to obtain the final mixed powder. The screw rotation speed was 1 r / s, the Ar ion beam flow rate was 12 L / min, and the mixing and dissociation time was 1 h. The final mixed powder had a Hall flow rate of 26 s / 50 g.

[0090] The final mixed powder was clad onto the substrate surface using an ultra-high-speed laser cladding method to obtain a metal-based Ti-BN ceramic particle-reinforced gradient composite coating.

[0091] The laser power is 1600W, the workpiece outer diameter rotational linear speed is 23m / min, the axial movement speed of the cladding head is 0.3mm / r, the powder-carrying gas flow rate is 7L / min, the protective gas flow rate is 6L / min, and the powder feeding rate is 34g / min.

[0092] The composite coating after cladding has an interface width of 75-85 μm, a porosity and crack defect rate of 0.15%, and an interface shear strength of 450 MPa. The shallow surface layer of this composite coating was tested for wear resistance according to the "GT / T 12444-2006 Metallic Materials Wear Test Method: Ring-Block Sliding Wear Test". The wear weight loss was 8 mg / h, and the volume percentage of in-situ self-generated Ti-BN ceramic particles reinforcing phase within 100 μm of the shallow surface of the composite coating was 45-50%.

[0093] Example 2-1

[0094] The composition and ratio of the metal-based Ti-BN ceramic particles in this embodiment are the same as those in Example 2. The closed turbine disk mechanical sand blowing, Ar ion beam dissociation, and ultra-high speed laser cladding processes are the same. The difference is that the Hall flow rate of the metal-based Ti-BN ceramic particles is 31s / 50g, and the screw rotation speed is 2r / s.

[0095] Among them, the laser power is 1600W, the workpiece outer diameter rotational linear speed is 23m / min, the axial movement speed of the cladding head is 0.3mm / r, the powder carrier gas flow rate is 7L / min, the protective gas flow rate is 6L / min, and the powder feeding rate is 34g / min.

[0096] The composite coating after cladding has an interface width of 74-82 μm, a porosity and crack defect rate of 0.15%, and an interface shear strength of 420 MPa. The shallow surface layer of this composite coating was tested for wear resistance according to the "GT / T 12444-2006 Metallic Materials Wear Test Method: Ring-Block Sliding Wear Test". The wear weight loss was 9 mg / h, and the volume percentage of in-situ self-generated Ti-BN ceramic particles reinforcing phase within 100 μm of the shallow surface of the composite coating was 45-50%.

[0097] Example 2-2

[0098] The composition and ratio of the metal-based Ti-BN ceramic particles in this embodiment are the same as those in Example 2. The closed turbine disk mechanical sand blowing, Ar ion beam dissociation, and ultra-high speed laser cladding processes are the same. The difference is that the Hall flow rate of the metal-based Ti-BN ceramic particles is 28s / 50g, and the Ar ion beam flow rate is 15L / min.

[0099] The laser power is 1600W, the workpiece outer diameter rotational linear speed is 23m / min, the axial movement speed of the cladding head is 0.3mm / r, the powder-carrying gas flow rate is 7L / min, the protective gas flow rate is 6L / min, and the powder feeding rate is 34g / min.

[0100] The composite coating after cladding has an interface width of 75-83 μm, a porosity and crack defect rate of 0.15%, and an interface shear strength of 435 MPa. The shallow surface layer of this composite coating was tested for wear resistance according to the "GT / T 12444-2006 Metallic Materials Wear Test Method: Ring-Block Sliding Wear Test". The wear weight loss was 7 mg / h, and the volume percentage of in-situ self-generated Ti-BN ceramic particles reinforcing phase within 100 μm of the shallow surface of the composite coating was 45-50%.

[0101] Example 3

[0102] The metal-based Ti-BN ceramic particle powder of this embodiment contains the following components in the following mass percentages: 431 stainless steel spherical powder: 70%, non-spherical reduced Ti powder: 19.6%, and flaky H-BN powder: 10.4%.

[0103] The sphericity of the 431 stainless steel spherical powder is 96%, the particle size is 15-53μm, and the Hall flow rate is 18s / 50g.

[0104] The non-spherical reduced Ti powder has a particle size distribution of 5-20 μm.

[0105] The fragmented H-BN powder has a particle size distribution of 3-5 μm.

[0106] The spherical metal powder serves as the metal matrix, while the non-spherical reduced Ti powder and the fragmented H-BN powder serve as in-situ reactants.

[0107] The original pre-alloyed mixed powder was thoroughly mixed and dissociated by a closed turbine disc mechanical sand blowing and Ar ion beam dissociation to obtain the final mixed powder. The screw rotation speed was 1 r / s, the Ar ion beam flow rate was 12 L / min, and the mixing and dissociation time was 1 h. The final mixed powder had a Hall flow rate of 34 s / 50 g.

[0108] The final mixed powder was clad onto the substrate surface using an ultra-high-speed laser cladding method to obtain a metal-based Ti-BN ceramic particle-reinforced gradient composite coating.

[0109] Among them, the laser power is 1800W, the workpiece outer diameter rotational linear speed is 21m / min, the axial movement speed of the cladding head is 0.35mm / r, the powder carrier gas flow rate is 9L / min, the protective gas flow rate is 7L / min, and the powder feeding rate is 36g / min.

[0110] The composite coating after cladding has an interface width of 78-90 μm, a porosity and crack defect rate of 0.05%, and an interface shear strength of 400 MPa. The shallow surface layer of this composite coating was tested for wear resistance according to the "GT / T 12444-2006 Metallic Materials Wear Test Method: Ring-Block Sliding Wear Test". The wear weight loss was 8 mg / h, and the volume percentage of in-situ self-generated Ti-BN ceramic particles reinforcing phase within 100 μm of the shallow surface of the composite coating was 50-55%.

[0111] Example 3-1

[0112] The composition and ratio of the metal-based Ti-BN ceramic particles in this embodiment are the same as those in Example 3. The closed turbine disk mechanical sand blowing, Ar ion beam dissociation, and ultra-high speed laser cladding processes are the same. The difference is that the Hall flow rate of the metal-based Ti-BN ceramic particles is 32s / 50g, and the screw rotation speed is 2r / s.

[0113] Among them, the laser power is 1800W, the workpiece outer diameter rotational linear speed is 21m / min, the axial movement speed of the cladding head is 0.35mm / r, the powder carrier gas flow rate is 9L / min, the protective gas flow rate is 7L / min, and the powder feeding rate is 36g / min.

[0114] The composite coating after cladding has an interface width of 77-88 μm, a porosity and crack defect rate of 0.05%, and an interface shear strength of 380 MPa. The shallow surface layer of this composite coating was tested for wear resistance according to the "GT / T 12444-2006 Metallic Materials Wear Test Method: Ring-Block Sliding Wear Test". The wear weight loss was 9 mg / h, and the volume percentage of in-situ self-generated Ti-BN ceramic particles reinforcing phase within 100 μm of the shallow surface of the composite coating was 50-55%.

[0115] Example 3-2

[0116] The composition and ratio of the metal-based Ti-BN ceramic particles in this embodiment are the same as those in Example 2. The closed turbine disk mechanical sand blowing, Ar ion beam dissociation, and ultra-high speed laser cladding processes are the same. The difference is that the Hall flow rate of the metal-based Ti-BN ceramic particles is 33s / 50g, and the Ar ion beam flow rate is 15L / min.

[0117] Among them, the laser power is 1800W, the workpiece outer diameter rotational linear speed is 21m / min, the axial movement speed of the cladding head is 0.35mm / r, the powder carrier gas flow rate is 9L / min, the protective gas flow rate is 7L / min, and the powder feeding rate is 36g / min.

[0118] The composite coating after cladding has an interface width of 78-87 μm, a porosity and crack defect rate of 0.05%, and an interface shear strength of 370 MPa. The shallow surface layer of this composite coating was tested for wear resistance according to the "GT / T 12444-2006 Metallic Materials Wear Test Method: Ring-Block Sliding Wear Test". The wear weight loss was 9 mg / h, and the volume percentage of in-situ self-generated Ti-BN ceramic particles reinforcing phase within 100 μm of the shallow surface of the composite coating was 50-55%.

[0119] Comparative Example 1

[0120] The metal-based Ti-BN ceramic particle powder of this comparative example contains the following components in the following mass percentages: 431 martensitic stainless steel spherical powder: 83%, non-spherical reduced Ti powder: 12%, and flaky H-BN powder: 5%, which does not meet the requirements of this invention.

[0121] The spherical powder of the 431 martensitic stainless steel has a sphericity of 96%, a particle size of 15-53 μm, and a Hall flow rate of 18 s / 50 g.

[0122] The non-spherical reduced Ti powder has a particle size distribution of 5-20 μm.

[0123] The fragmented H-BN powder has a particle size distribution of 3-5 μm.

[0124] The spherical metal powder serves as the metal matrix, while the non-spherical reduced Ti powder and the fragmented H-BN powder serve as in-situ reactants.

[0125] The original pre-alloyed mixed powder was thoroughly mixed and dissociated by a closed turbine disc mechanical sand blowing and Ar ion beam dissociation to obtain the final mixed powder. The screw rotation speed was 1 r / s, the Ar ion beam flow rate was 12 L / min, and the mixing and dissociation time was 1 h. The final mixed powder had a Hall flow rate of 31 s / 50 g.

[0126] The final mixed powder was clad onto the substrate surface using an ultra-high-speed laser cladding method to obtain a metal-based Ti-BN ceramic particle-reinforced gradient composite coating.

[0127] The laser power is 1700W, the workpiece outer diameter rotational linear speed is 22m / min, the axial movement speed of the cladding head is 0.33mm / r, the powder-carrying gas flow rate is 8L / min, the protective gas flow rate is 6.6L / min, and the powder feeding rate is 35g / min.

[0128] The composite coating after cladding has an interface width of 50-62 μm, a porosity and crack defect rate of 0.38%, and an interface shear strength of 380 MPa. The shallow surface layer of this composite coating was tested for wear resistance according to the "GT / T 12444-2006 Metallic Materials Wear Test Method: Ring-Block Sliding Wear Test". The wear weight loss was 12 mg / h, and the volume percentage of in-situ self-generated Ti-BN ceramic particles reinforcing phase within 100 μm of the shallow surface of the composite coating was 40-45%.

[0129] Comparative Example 2

[0130] The metal-based Ti-BN ceramic particle powder of this comparative example contains the following components in the following mass percentages: 431 martensitic stainless steel spherical powder: 80%, non-spherical reduced Ti powder: 12%, and flaky H-BN powder: 8%, which does not meet the requirements of this invention.

[0131] The spherical powder of the 431 martensitic stainless steel has a sphericity of 96%, a particle size of 15-53 μm, and a Hall flow rate of 18 s / 50 g.

[0132] The non-spherical reduced Ti powder has a particle size distribution of 5-20 μm.

[0133] The fragmented H-BN powder has a particle size distribution of 3-5 μm.

[0134] The spherical metal powder serves as the metal matrix, while the non-spherical reduced Ti powder and the fragmented H-BN powder serve as in-situ reactants.

[0135] The original pre-alloyed mixed powder was thoroughly mixed and dissociated by a closed turbine disc mechanical sand blowing and Ar ion beam dissociation to obtain the final mixed powder. The screw rotation speed was 1 r / s, the Ar ion beam flow rate was 12 L / min, and the mixing and dissociation time was 1 h. The final mixed powder had a Hall flow rate of 33 s / 50 g.

[0136] The final mixed powder was clad onto the substrate surface using an ultra-high-speed laser cladding method to obtain a metal-based Ti-BN ceramic particle-reinforced gradient composite coating.

[0137] The laser power is 1700W, the workpiece outer diameter rotational linear speed is 22m / min, the axial movement speed of the cladding head is 0.33mm / r, the powder-carrying gas flow rate is 8L / min, the protective gas flow rate is 6.6L / min, and the powder feeding rate is 35g / min.

[0138] The composite coating after cladding has an interface width of 52-64 μm, a porosity and crack defect rate of 0.40%, and an interface shear strength of 300 MPa. The shallow surface layer of this composite coating was tested for wear resistance according to the "GT / T 12444-2006 Metallic Materials Wear Test Method: Ring-Block Sliding Wear Test". The wear weight loss was 11 mg / h, and the volume percentage of in-situ self-generated Ti-BN ceramic particles reinforcing phase within 100 μm of the shallow surface of the composite coating was 45-50%.

[0139] Comparative Example 3

[0140] The metal-based Ti-BN ceramic particle powder of this comparative example contains the following components in the following mass percentages: 431 stainless steel spherical powder: 66%, non-spherical reduced Ti powder: 22%, and flaky H-BN powder: 12%, which does not meet the requirements of this invention.

[0141] The sphericity of the 431 stainless steel spherical powder is 96%, the particle size is 15-53μm, and the Hall flow rate is 18s / 50g.

[0142] The non-spherical reduced Ti powder has a particle size distribution of 5-20 μm.

[0143] The fragmented H-BN powder has a particle size distribution of 3-5 μm.

[0144] The spherical metal powder serves as the metal matrix, while the non-spherical reduced Ti powder and the fragmented H-BN powder serve as in-situ reactants.

[0145] The original mixed powder was thoroughly mixed and dissociated using a closed turbine disc mechanical sand-throwing and Ar ion beam dissociation process to obtain the final mixed powder. The screw rotation speed was 1 r / s, the Ar ion beam flow rate was 12 L / min, and the mixing and dissociation time was 1 hour. Because the final mixed powder lacks Hall flow characteristics, powder feeding and cladding in ultra-high-speed laser cladding equipment cannot be achieved through powder flow.

[0146] Comparative Example 4

[0147] The metal-based Ti-BN ceramic particle powder of this comparative example contains the following components in weight percentage: 431 stainless steel spherical powder: 75%, non-spherical reduced Ti powder: 16.35%, and flaky H-BN powder: 8.65%.

[0148] The sphericity of the 431 stainless steel spherical powder is 96%, the particle size is 15-53μm, and the Hall flow rate is 18s / 50g.

[0149] The non-spherical reduced Ti powder has a particle size distribution of 5-20 μm.

[0150] The fragmented H-BN powder has a particle size distribution of 3-5 μm.

[0151] The spherical metal powder serves as the metal matrix, while the non-spherical reduced Ti powder and the fragmented H-BN powder serve as in-situ reactants.

[0152] The original pre-alloyed mixed powder was thoroughly mixed and dissociated using a closed turbine disc mechanical sand blowing and Ar ion beam dissociation to obtain the final mixed powder. The screw rotation speed was 0.5 r / s, the Ar ion beam flow rate was 12 L / min, and the mixing and dissociation time was 1 hour. Because the final mixed powder lacks Hall flow characteristics, it cannot be used for powder feeding and cladding in ultra-high-speed laser cladding equipment.

[0153] Comparative Example 5

[0154] The metal-based Ti-BN ceramic particles in this comparative example have the same composition and proportion as those in Comparative Example 4. The closed turbine disk mechanical sand blowing, Ar ion beam dissociation, and ultra-high-speed laser cladding processes are the same. The difference is that the Ar ion beam flow rate of the metal-based Ti-BN ceramic particles is 10 L / min. The final mixed powder still has no Hall flowability, so powder feeding and cladding of the ultra-high-speed laser cladding equipment cannot be achieved through powder flow.

[0155] Comparative Example 6

[0156] The powder used in this comparative example is 100% spherical powder of 431 martensitic stainless steel.

[0157] The sphericity of the 431 stainless steel spherical powder is 96%, the particle size is 15-53μm, and the Hall flow rate is 18s / 50g.

[0158] The above-mentioned 431 stainless steel spherical powder was clad onto the surface of the substrate using an ultra-high-speed laser cladding method to obtain a 431 stainless steel base coating.

[0159] The laser power is 1700W, the workpiece outer diameter rotational linear speed is 22m / min, the axial movement speed of the cladding head is 0.33mm / r, the powder-carrying gas flow rate is 8L / min, the protective gas flow rate is 6.6L / min, and the powder feeding rate is 35g / min.

[0160] The composite coating after cladding has an interface width of 7-10 μm, a porosity and crack defect rate of 5-10%, and an interface shear strength of 210 MPa. The shallow coating of the 431 stainless steel base was tested for wear resistance according to "GT / T12444-2006 Metallic Materials Wear Test Methods - Ring-Block Sliding Wear Test", and the wear weight reduction was 27 mg / h.

[0161] Comparative Example 7

[0162] This comparative example uses Cr12MoV cold work die steel, which has undergone forging and heat treatment and is free of porosity and cracks. Wear resistance testing was conducted according to "GT / T 12444-2006 Metallic Materials Wear Test Method: Ring-Block Sliding Wear Test". The wear weight reduction was 19 mg / h. The wear morphology of this die material under the same wear conditions as the metal-based Ti-BN ceramic particle-reinforced gradient composite coating of Example 1 of this invention is as follows: Figure 5 As shown.

[0163] Table 1. Specific component ratios and process parameters for the embodiments and comparative examples.

[0164]

[0165] Table 2. Coating performance of the examples and comparative examples

[0166]

[0167] As shown in Table 2, after restoring its fluidity, the metal-based Ti-BN ceramic particle powder of the present invention achieves a Hall flow rate of ≤35s / 50g. Subsequently, through ultra-high-speed laser cladding technology in the additive manufacturing of rotating shaft parts, the cladding interface width of this composite coating (65-90μm) is more than doubled compared to the interface width of metal-based cladding coatings (5-10μm) directly mixed with ceramic phase under the same process. Simultaneously, the in-situ synthesis and self-generation of the Ti-BN ceramic particle reinforcing phase in the metal-based Ti-BN ceramic particle composite coating of the present invention are achieved. The content gradient of the self-generated Ti-BN ceramic particle reinforcement phase changes along the vertical direction (coating thickness direction) of the composite coating under the action of high-speed rotating centrifugal force, and there is no particle agglomeration effect. The volume percentage of the in-situ self-generated Ti-BN ceramic particle reinforcement phase within the shallow position (within 100μm) of the composite coating is not less than 40%. The wear resistance is reduced by more than half compared with the wear resistance weight loss of Cr12MoV cold work die steel. Compared with metal matrix ceramic composite coatings with ceramic phase directly mixed in, the bonding shear strength of the matrix interface is increased by more than 50%, and the porosity and cracks are reduced to below 3.5%.

[0168] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A metal-based Ti-BN ceramic particle-reinforced gradient composite coating, characterized in that, The composite coating includes a Ti-BN ceramic particle reinforcing phase, which includes TiN, TiB2 and a small amount of Ti4B2N3; The content of the Ti-BN ceramic particle reinforcing phase is distributed in a gradient along the thickness direction of the composite coating; The metal-based Ti-BN ceramic particle-reinforced gradient composite coating is prepared through the following steps: S1: According to the composition design, spherical metal powder, non-spherical reduced Ti powder and sharded H-BN powder are mixed to obtain the original pre-alloyed mixed powder; S2: The original pre-alloyed mixed powder is thoroughly mixed and dissociated by a closed turbine disc mechanical sand blowing and Ar ion beam dissociation to obtain mixed powder. The mixed powder is dried and then vacuum sealed for later use. S3: Set the process parameters for ultra-high-speed laser cladding; S4: Clamp the smooth and defect-free metal bar workpiece to be clad onto the laser cladding device, and adjust the laser spot and the powder spot to converge at a point in space, ensuring that the point is located 0.2mm-0.8mm above the starting cladding end of the workpiece. S5: Using an ultra-high-speed laser cladding method, the mixed powder in S2 is clad onto the substrate surface to obtain a metal-based Ti-BN ceramic particle-reinforced gradient composite coating. In step S1, the spherical metal powder is either Fe-based stainless steel or Ni-based high-temperature alloy powder material, with a particle size of 15-53 μm, and accounts for 70-80% of the mass of the original pre-alloyed mixed powder. The non-spherical reduced Ti powder has a particle size of 5-20 μm and accounts for 13.1-19.6% of the mass of the original pre-alloyed mixed powder. The flaky H-BN powder has a particle size of 3-5 μm and accounts for 6.9-10.4% of the mass of the original pre-alloyed mixed powder. The spherical metal powder serves as the metal matrix, while the non-spherical reduced Ti powder and the fragmented H-BN powder serve as in-situ reactants. In step S2, the Hall flow rate of the mixed powder is ≤35s / 50g; In step S3, the process parameters for ultra-high-speed laser cladding are: laser power 1600-1800W, workpiece outer diameter rotational linear speed 21-23m / min, cladding head axial movement speed 0.3-0.35mm / r, powder carrier gas flow rate 7-9L / min, protective gas flow rate 6-7L / min, and powder feeding rate 34-36g / min. The composite coating has a cladding interface width of 65-90 μm, a porosity and crack defect rate of ≤3.5%, and an in-situ self-generated Ti-BN ceramic particle reinforcement phase volume percentage of ≥40% within 100 μm of the shallow surface of the composite coating.

2. The metal-based Ti-BN ceramic particle-reinforced gradient composite coating according to claim 1, characterized in that, The cladding interface width of the composite coating is 68-90 μm.

3. A method for preparing a metal-based Ti-BN ceramic particle-reinforced gradient composite coating, used to prepare the metal-based Ti-BN ceramic particle-reinforced gradient composite coating according to any one of claims 1-2, characterized in that, Includes the following steps: S1: According to the composition design, spherical metal powder, non-spherical reduced Ti powder and sharded H-BN powder are mixed to obtain the original pre-alloyed mixed powder; S2: The original pre-alloyed mixed powder is thoroughly mixed and dissociated by a closed turbine disc mechanical sand blowing and Ar ion beam dissociation to obtain mixed powder. The mixed powder is dried and then vacuum sealed for later use. S3: Set the process parameters for ultra-high-speed laser cladding; S4: Clamp the smooth and defect-free metal bar workpiece to be clad onto the laser cladding device, and adjust the laser spot and the powder spot to converge at a point in space, ensuring that the point is located 0.2mm-0.8mm above the starting cladding end of the workpiece. S5: Using an ultra-high-speed laser cladding method, the mixed powder in S2 is clad onto the substrate surface to obtain a metal-based Ti-BN ceramic particle-reinforced gradient composite coating. In step S1, the spherical metal powder is either Fe-based stainless steel or Ni-based high-temperature alloy powder material, with a particle size of 15-53 μm, and accounts for 70-80% of the mass of the original pre-alloyed mixed powder. The non-spherical reduced Ti powder has a particle size of 5-20 μm and accounts for 13.1-19.6% of the mass of the original pre-alloyed mixed powder. The flaky H-BN powder has a particle size of 3-5 μm and accounts for 6.9-10.4% of the mass of the original pre-alloyed mixed powder. The spherical metal powder serves as the metal matrix, while the non-spherical reduced Ti powder and the fragmented H-BN powder serve as in-situ reactants. In step S2, the Hall flow rate of the mixed powder is ≤35s / 50g; In step S3, the process parameters for the ultra-high-speed laser cladding are: laser power 1600-1800W, workpiece outer diameter rotational linear speed 21-23m / min, cladding head axial movement speed 0.3-0.35mm / r, powder carrier gas flow rate 7-9L / min, protective gas flow rate 6-7L / min, and powder feeding rate 34-36g / min.

4. The preparation method according to claim 3, characterized in that, In step S1, by mass percentage, the spherical metal powder is 75-80%, the non-spherical reduced Ti powder is 16.35-19.6%, and the flaky H-BN powder is 8.65-10.4%.

5. The preparation method according to claim 4, characterized in that, In step S2, the Hall flow rate of the mixed powder is ≤34s / 50g.

6. The preparation method according to claim 5, characterized in that, In step S2, during the closed turbine disc mechanical sand blowing process, the screw rotation speed is ≥1r / s.

7. The preparation method according to claim 6, characterized in that, In step S2, during the Ar ion beam dissociation process, the Ar ion beam flow rate is ≥12L / min.

8. The preparation method according to claim 7, characterized in that, In step S2, the interaction time of the sealed turbine disc mechanical sand blowing and Ar ion beam dissociation is ≥1h.

9. The preparation method according to claim 8, characterized in that, In step S3, the process parameters for the ultra-high-speed laser cladding are as follows: laser power 1700-1800W, workpiece outer diameter rotational linear speed 22-23m / min, cladding head axial movement speed 0.33-0.35mm / r, powder carrier gas flow rate 8-9L / min, protective gas flow rate 6.6-7L / min, and powder feeding rate 35-36g / min.

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