High-strength and high-toughness nickel-based wear-resistant alloy coating and preparation method thereof

Abstract

The invention provides a high-strength and high-toughness nickel-based wear-resistant alloy component and a preparation method thereof, and the alloy is composed of the following components in percentage by mass: 16-19% of Cr, 3-5% of B, 0.2-0.6% of C, 3-6% of Si, 3-10% of Fe, 2.2-3.2% of Ti and the balance of Ni and inevitable impurities. The preparation method comprises the steps that alloy powder for laser cladding is obtained through gas atomization according to alloy components and the mass fraction of the alloy components; alloy powder is synchronously conveyed to the pretreated Q235 steel base plate in a coaxial powder feeding mode; and carrying out laser cladding treatment to obtain the alloy coating. Through the solid solution strengthening effect of key alloy elements such as Cr and Ti and the needle-shaped hard phase generated in the laser cladding solidification process, the resistance to abrasive particles is improved. According to the alloy component, the alloy coating has excellent obdurability, the tribological performance of the alloy is improved, a novel alloy component and a preparation process are provided for laser cladding, and the alloy component has important practical significance for promoting application of the laser cladding technology.

Description

Technical Field

[0001] This invention belongs to the field of alloy surface coating modification technology, specifically relating to the field of laser cladding. In particular, for components that require both high strength and toughness, it provides a nickel-based wear-resistant alloy composition and its preparation method, the composition of which is used to prepare wear-resistant coatings by laser cladding. Background Technology

[0002] In key industrial sectors such as machinery manufacturing, mining and metallurgy, and aerospace, core components like crusher hammers, excavator bucket teeth, gear shafts, and turbine blades often operate under harsh conditions of high-speed friction and strong impact coupling for extended periods. Failure in these components typically begins with surface damage, as their surfaces must continuously withstand repeated abrasion from external media. However, traditional nickel-based protective coatings generally suffer from an imbalance between strength and toughness, exhibiting a trade-off between wear resistance and toughness. In practical applications, they are prone to cracking, unable to withstand high-intensity friction, and ultimately lead to premature component failure. Therefore, developing nickel-based alloy coatings that combine high hardness, high wear resistance, and excellent toughness has become an urgent need to improve the surface protection capabilities of industrial components.

[0003] Ni60 alloy is one of the most widely used nickel-based wear-resistant materials in the field of laser cladding. Its excellent wear resistance makes it irreplaceable in surface strengthening of wear parts. The alloy's performance advantage stems from the synergistic regulation of multiple alloying elements: chromium forms a dense chromium oxide passivation film on the coating surface, effectively improving oxidation and corrosion resistance; boron and silicon, as strong deoxidizers and slagging agents, improve the wetting and flow characteristics of the molten pool and combine with matrix elements such as nickel and chromium to generate a large number of hard intermetallic compounds, significantly improving the coating's hardness and wear resistance. However, the Ni60 alloy system still faces significant bottlenecks in practical engineering applications. Under load, the coating is prone to strength-toughness imbalance, making it difficult to meet the stringent requirements for strength-toughness matching under high-strength and high-wear conditions. Therefore, performance upgrades urgently need to be achieved through dual optimization of composition design and preparation processes.

[0004] Based on the technical limitations of existing Ni60 alloy coatings and the actual needs of industrial components, this invention proposes a nickel-based wear-resistant alloy composition and its preparation method. This composition is used for laser cladding to prepare wear-resistant coatings. The core innovation lies in overcoming the challenge of balancing hardness and toughness through precise control of the alloy composition, gas atomization powder preparation process, and laser cladding process. Coating hardness is the core support for wear resistance; higher hardness enhances the coating's ability to resist external friction and extrusion, reduces surface material loss, and thus directly improves wear resistance. In terms of composition design, this invention introduces 2.2-3.2% titanium. Titanium, through solute atom segregation and lattice distortion effects, regulates the growth behavior of the chromium-rich reinforcing phase, causing its morphology to gradually change from blocky to needle-like. By controlling the interfacial bonding state between the matrix phase and the reinforcing phase, a balance between strength and toughness is achieved in the alloy. In terms of preparation process, a process of "precise batching - gas atomization powder preparation - laser cladding" is adopted to ensure uniform dispersion of the alloy powder composition, avoiding the composition segregation problem caused by traditional mixing methods. Combined with optimized laser cladding parameters, a strong metallurgical bond between the coating and the substrate is achieved. Compared to existing technologies, the nickel-based wear-resistant alloy coating prepared by this method maintains both high strength and good toughness, effectively solving the pain points of traditional coatings that are "wear-resistant but not crack-resistant, or crack-resistant but not wear-resistant." This preparation method not only provides data support and technical reference for the industrial production of Ni60 alloy for laser cladding, but also offers new ideas and methods for the research and development of nickel-based wear-resistant alloys. Summary of the Invention

[0005] Purpose of the invention: In view of the above, the purpose of this invention is to provide a nickel-based wear-resistant alloy composition and its preparation method. The composition is used to prepare a wear-resistant coating by laser cladding. The coating prepared by this invention has excellent wear resistance.

[0006] Technical solution: To achieve the above objectives, the present invention can be implemented through the following technical solution.

[0007] This invention provides a nickel-based wear-resistant alloy composition and its preparation method. The composition is used for laser cladding to prepare a wear-resistant coating, and includes the following steps:

[0008] S1: According to the preset alloy composition ratio, accurately weigh the alloying elements such as chromium, boron, carbon, silicon, nickel, titanium, and iron using an electronic balance with an accuracy of 0.0001g.

[0009] S2: Place all the weighed raw materials into a vacuum induction furnace and melt them into ingots.

[0010] S3: The alloy ingot is surface pickled and then vacuum dried.

[0011] S4: Place the ingot in a water-cooled copper crucible and use vacuum induction melting to convert it into a homogeneous liquid phase. High-purity argon gas is introduced during the melting process.

[0012] S5: High-pressure argon gas is used to break the molten alloy liquid into micron-sized droplets at high speed, and then rapidly cooled and solidified in an argon protective atmosphere to form spherical alloy powder with a particle size of 45-106 μm. The oxygen content is controlled below 500 ppm throughout the process.

[0013] S6: The powder obtained in S5 is dried in a vacuum drying oven, and the alloy powder is synchronously conveyed to the pretreated Q235 steel substrate using a coaxial powder feeding method; an alloy coating is obtained by laser cladding.

[0014] Preferably, the alloy composition of S1 includes the following components by mass percentage: Cr 16-19%, B 3-5%, C 0.2-0.6%, Si 3-6%, Fe 3-10%, Ti 2.2-3.2%, with the balance being Ni, and the purity of each element is not less than 99.9 wt.%.

[0015] Preferably, the pickling solution in S3 is 10% HNO3 + 3% HF.

[0016] Preferably, the vacuum induction melting parameters in S4 are 1450-1550℃ / 10-2 Pa; and the argon purity is 99.99%.

[0017] Preferably, the high pressure in S5 is 1.8 MPa; the cooling rate is 105-106 K / s.

[0018] Preferably, the drying process in S6 is carried out at a temperature of 80°C for 2 hours.

[0019] Preferably, the process parameters for laser cladding in S6 are as follows: laser power of 2000-2500 W, scanning rate of 4-10 mm / s, spot diameter of 4 mm, powder feeding rate of 15 g / min, substrate preheating of 300℃-350℃, protective gas of argon, and gas flow rate of 2-5 L / min.

[0020] The innovative aspects of this invention are as follows:

[0021] (1) Breaking away from the traditional approach of relying on the formation of hard carbides to improve wear resistance of Ni60 alloy, 2.2-3.2% titanium element is introduced. The morphology of the chromium-rich strengthening phase is controlled to change from blocky to needle-like by utilizing the solute atom segregation and lattice distortion effect of titanium.

[0022] (2) Optimization of the entire process of “composition-powdering-cladding”. An integrated process system of “precise batching-gas atomization powdering-laser cladding” is constructed. Unlike the composition segregation problem caused by traditional mixing powdering, gas atomization powdering can ensure uniform dispersion of alloy powder components. Combined with matching laser cladding parameters, metallurgical bonding between the coating and the substrate is achieved.

[0023] Beneficial effects: Compared with the prior art, the present invention has the following advantages:

[0024] (1) The high-strength and tough nickel-based wear-resistant alloy coating powder for laser cladding prepared by the present invention has both excellent toughness and higher hardness. It can prepare a high-strength and tough nickel-based wear-resistant alloy coating with excellent process performance. It can not only provide reliable protection for the surface of metal components, but also the coating is particularly suitable for laser cladding strengthening of alloy components with high surface wear resistance requirements, which can greatly improve the tribological properties of the cladding layer.

[0025] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0026] Figure 1 Flowchart for preparing wear-resistant coatings using laser cladding;

[0027] Figure 2 Powder morphology diagram for gas atomization powder preparation;

[0028] Figure 3 Comparison of the microstructure of wear-resistant Ni60 coating: (a) Example 1 (b) Example 2;

[0029] Figure 4 A comparison chart of friction coefficients for wear-resistant coatings;

[0030] Figure 5 A comparison chart of wear amount and wear rate of wear-resistant coatings;

[0031] Figure 6 The wear mechanism diagrams for the wear-resistant coating are shown in (a) and (b) for Example 2, and (c) and (d) for Example 1.

[0032] Figure 7 The three-dimensional wear mark morphology of the wear-resistant coating is shown in Example 2 (a) and Example 1 (b). Detailed Implementation

[0033] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0034] The various exemplary embodiments provided below are intended to provide a more detailed explanation of some of the technical features, specific implementation schemes and application scenarios of the present invention. They should not be construed as limiting the scope of protection of the present invention, but should be regarded as a specific presentation of the implementable paths in the technical solutions of the present invention.

[0035] It should be clarified that the terminology used in this invention is only for describing specific embodiments and is not intended to limit the technical solutions of this invention. Furthermore, regarding the numerical ranges involved in this invention, it should be understood that every intermediate value between the upper and lower limits of the range has been specifically disclosed; simultaneously, every smaller numerical range formed by any stated value or intermediate value within a defined numerical range and another stated value or other intermediate values ​​within the same numerical range is also included within the scope of protection of this invention. For these smaller numerical ranges, the upper and lower limits can be independently included in the range or independently excluded from the range, depending on the actual application requirements.

[0036]

Example 1

[0037] This embodiment provides an alloy composition for a high-strength and tough nickel-based wear-resistant alloy coating, comprising the following components by mass percentage: Cr 16-19%, B 3-5%, C 0.2-0.6%, Si 3-6%, Fe 3-10%, Ti 2.2-3.2%, with the balance being Ni. The percentages are by mass percentage.

[0038] The specific process of the method in this embodiment is as follows: Figure 1 As shown, it includes the following steps:

[0039] S1: According to the preset alloy composition ratio, accurately weigh the alloying elements such as chromium, boron, carbon, silicon, nickel, titanium, and iron using an electronic balance with an accuracy of 0.0001g. The alloy composition ratio, by mass percentage, includes the following components: Cr 16-19%, B 3-5%, C 0.2-0.6%, Si 3-6%, Fe 3-10%, Ti 2.2-3.2%, with the balance being Ni; the purity of each element in the raw materials shall not be less than 99.9 wt.%.

[0040] S2: Place all the weighed raw materials into a vacuum induction furnace and melt them into ingots.

[0041] S3: The alloy ingot is surface pickled and then vacuum dried. The pickling solution is 10% HNO3 + 3% HF.

[0042] S4: The ingot is placed in a water-cooled copper crucible and converted into a homogeneous liquid phase using vacuum induction melting, with high-purity argon gas introduced during the melting process. The vacuum induction melting parameters are 1450-1550℃ / 10-2 Pa; the argon gas purity is 99.99%.

[0043] S5: High-pressure argon gas is used to rapidly break the molten alloy liquid into micron-sized droplets, which are then rapidly cooled and solidified in an argon-protected atmosphere to form spherical alloy powder with a particle size of 45-106 μm. The oxygen content is controlled below 500 ppm throughout the process. The high pressure is 1.8 MPa, and the cooling rate is 105-106 K / s.

[0044] S6: The powder obtained in S5 is dried in a vacuum drying oven. The alloy powder is then synchronously fed onto a pretreated Q235 steel substrate using a coaxial powder feeding method. An alloy coating is obtained through laser cladding. The drying temperature is 80℃ and the time is 2 hours. The laser cladding process parameters are: laser power 2000-2500 W, scanning rate 4-10 mm / s, spot diameter 4 mm, powder feeding rate 15 g / min, substrate preheating 300℃-350℃, protective gas argon, and gas flow rate 2-5 L / min.

[0045] The powder microstructure, microstructure, and tribological properties in this embodiment are as follows: Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 As shown.

[0046]

Example 2

[0047] This embodiment provides an alloy composition for laser cladding, comprising the following components by mass percentage: Cr 17.88%, B 3.05%, C 0.85%, Si 4.25%, Fe 13.5%, with the balance being Ni. The proportions are by mass percentage. The powder is dried in a vacuum drying oven and then synchronously fed onto a pre-treated Q235 steel substrate using a coaxial powder feeding method. An alloy coating is obtained through laser cladding. The drying temperature is 80℃, and the time is 2 hours. The laser cladding process parameters are: laser power 2000-2500 W, scanning rate 4-10 mm / s, spot diameter 4 mm, powder feeding rate 15 g / min, substrate preheating 300℃-350℃, protective gas argon, and gas flow rate 2-5 L / min.

[0048] In this embodiment, the alloy powder was purchased, and the above alloy composition was used for laser cladding to prepare a wear-resistant coating.

[0049] The microstructure and tribological properties of the alloy in this embodiment are as follows: Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 As shown.

[0050] Performance Testing: To verify the effectiveness and practical results of the present invention, the friction coefficient, wear amount, and wear rate of the cladding coatings prepared in Examples 1 and 2 will be tested separately in this embodiment. The specific test results and analysis are as follows:

[0051] Wear resistance performance analysis of alloy wear-resistant coating: The wear resistance performance test of the wear-resistant coatings in Examples 1 and 2 used Si3N4 as the friction pair, the load was 40 N, the friction method was reciprocating friction, the wear time was 60 min, and then the wear amount was tested, and the wear rate was calculated by formula.

[0052] Table 1

[0053] name <![CDATA[Wear amount (mm 3 )]]> <![CDATA[Wear rate (mm³·N -1 ·m -1 )]]> Example 1 5.99 0.0719 Example 2 7.46 0.0895

[0054] As shown in Table 1, the analysis of the tribological properties of the alloy cladding coating revealed that the wear mechanism of Examples 1 and 2 is mainly abrasive wear. Example 1 has a lower and more stable coefficient of friction, less wear, and a lower wear rate. Therefore, the tribological properties of Example 1 are better than those of Example 2.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A high-strength, high-toughness nickel-based wear-resistant alloy composition, characterized in that, The composition by mass percentage is as follows: Cr 16-19%, B 3-5%, C 0.2-0.6%, Si 3-6%, Fe 3-10%, Ti 2.2-3.2%, with the balance being Ni.

2. The composition of a nickel-based wear-resistant alloy according to claim 1, characterized in that, The alloy composition is used for laser cladding to prepare wear-resistant coatings.

3. The method for preparing a nickel-based wear-resistant alloy composition according to claim 1, wherein the composition is used for laser cladding to prepare a wear-resistant coating, characterized in that, Includes the following steps: S1: According to the preset alloy composition ratio, accurately weigh the alloying elements such as chromium, boron, carbon, silicon, nickel, titanium, and iron using an electronic balance with an accuracy of 0.0001g. S2: Place all the weighed raw materials into a vacuum induction furnace and melt them into ingots. S3: The alloy ingot is surface pickled and then vacuum dried. S4: Place the ingot in a water-cooled copper crucible and use vacuum induction melting to convert it into a homogeneous liquid phase. High-purity argon gas is introduced during the melting process. S5: High-pressure argon gas is used to break the molten alloy liquid into micron-sized droplets at high speed, and then rapidly cooled and solidified in an argon protective atmosphere to form spherical alloy powder with a particle size of 45-106 μm. The oxygen content is controlled below 500 ppm throughout the process. S6: The powder obtained in S5 is dried in a vacuum drying oven. The alloy powder is then synchronously fed onto the pretreated Q235 steel substrate using a coaxial powder feeding method. The alloy coating is obtained by laser cladding.

4. A method for preparing a nickel-based wear-resistant alloy composition according to claim 3, wherein the composition is used for laser cladding to prepare a wear-resistant coating, characterized in that, The alloy composition of S1 includes the following components by mass percentage: Cr 16-19%, B 3-5%, C 0.2-0.6%, Si 3-6%, Fe 3-10%, Ti 2.2-3.2%, with the balance being Ni. The purity of each element in the raw materials is not less than 99.9 wt.%.

5. The method for preparing a nickel-based wear-resistant alloy composition according to claim 3, wherein the composition is used for laser cladding to prepare a wear-resistant coating, characterized in that, The pickling solution in S3 is 10% HNO3 + 3% HF.

6. The method for preparing a nickel-based wear-resistant alloy composition according to claim 3, wherein the composition is used for laser cladding to prepare a wear-resistant coating, characterized in that, The vacuum induction melting parameters in S4 are 1450-1550℃ / 10 -2 Pa; Argon purity is 99.99%.

7. The method for preparing a nickel-based wear-resistant alloy composition according to claim 3, wherein the composition is used for laser cladding to prepare a wear-resistant coating, characterized in that, The high-pressure component in S5 is 1.8 MPa; the cooling rate is 10. 5 -10 6 K / s.

8. The method for preparing a nickel-based wear-resistant alloy composition according to claim 3, wherein the composition is used for laser cladding to prepare a wear-resistant coating, characterized in that, In step S6, the drying temperature is 80℃ and the time is 2 hours.

9. A method for preparing a nickel-based wear-resistant alloy composition according to claim 3, wherein the composition is used for laser cladding to prepare a wear-resistant coating, characterized in that, The laser cladding process parameters in step S6 are as follows: laser power of 2000-2500 W, scanning rate of 4-10 mm / s, spot diameter of 4 mm, powder feeding rate of 15 g / min, substrate preheating of 300℃-350℃, protective gas of argon, and gas flow rate of 2-5 L / min.

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