1、铜表面激光熔覆NiCrWB合金的组织结构与耐磨性能研究Abstract: In this study, NiCrWB alloy was laser clad onto copper substrate, and the microstructure and wear resistance of the clad layer were investigated. The results showed that the clad layer had a dense microstructure, and the microhardness increased significantly afte
2、r laser cladding. The wear resistance of the clad layer was much better than that of the copper substrate, and the wear mechanism was mainly abrasive wear and adhesive wear.IntroductionCopper is a widely used engineering material due to its excellent thermal conductivity and electrical conductivity.
3、 However, its poor wear resistance limits its application in many fields, such as high load and high-speed sliding wear. Laser cladding is a promising method to improve the wear resistance of copper by applying a wear-resistant coating on its surface. NiCrWB alloy is a kind of high hardness and high
4、 wear-resistant alloy, which has been widely used in the field of wear-resistant materials. In this study, NiCrWB alloy was laser clad onto copper substrate, and the microstructure and wear resistance of the clad layer were investigated.ExperimentalThe copper substrate was cleaned and polished befor
5、e laser cladding. NiCrWB alloy powder was used as the cladding material, and the laser cladding process was carried out under the following parameters: laser power of 800 W, scanning speed of 1.5 m/min, powder feeding rate of 8 g/min, and a spot size of 2 mm. The clad layer thickness was about 1.5 m
6、m. The microstructure of the clad layer and the substrate was observed by scanning electron microscopy (SEM). Microhardness test and wear resistance test were also conducted.Results and discussionThe SEM images of the clad layer and the substrate are shown in Figure 1. The clad layer had a dense mic
7、rostructure, and fine dendrites were observed in the microstructure. The elemental mapping results showed that the distribution of Ni, Cr, W, and B elements was relatively uniform in the clad layer. The microhardness of the clad layer was significantly higher than that of the substrate, as shown in
8、Figure 2. The maximum microhardness value in the clad layer was around 700 Hv, while that of the substrate was about 80 Hv.The wear resistance of the clad layer and the substrate was evaluated by a pin-on-disk test. The results are shown in Figure 3. The weight loss of the clad layer was much lower
9、than that of the substrate, which means that the wear resistance of the clad layer was much better than that of the substrate. The wear mechanism of the clad layer was mainly abrasive wear and adhesive wear, as indicated by the SEM images of the worn surface.ConclusionsIn summary, NiCrWB alloy was s
10、uccessfully laser clad onto copper substrate, and a dense microstructure was formed. The microhardness of the clad layer was significantly higher than that of the substrate. The wear resistance of the clad layer was much better than that of the substrate, and the wear mechanism was mainly abrasive w
11、ear and adhesive wear. The results indicate that laser cladding of NiCrWB alloy is an effective method to improve the wear resistance of copper.In addition to improving the wear resistance of copper, laser cladding can also enhance other properties of the substrate, such as corrosion resistance, the
12、rmal resistance, and even add new functionalities, such as lubricity or electrical conductivity. Laser cladding has the advantage of precise control over the clad layer thickness, composition, and microstructure. The selection of cladding material, process parameters, and substrate preparation can g
13、reatly affect the performance of the clad layer.NiCrWB alloy is a typical wear-resistant alloy, which contains a high percentage of hard carbides and borides, and has a high melting point and excellent oxidation resistance. The use of this alloy as a cladding material can significantly increase the
14、wear resistance of the substrate. However, the laser cladding process can also introduce defects, such as pores, cracks, and residual stresses, which may affect the mechanical properties of the clad layer. Therefore, post-treatment, such as polishing, heat treatment, or shot peening, may be necessar
15、y to improve the quality of the clad layer.Laser cladding of NiCrWB alloy on copper can be applied in various industrial sectors, such as machinery, electronics, automotive, and aerospace. For example, it can be used as a protective coating for copper electrical contacts to prevent wear and oxidatio
16、n. It can also be used as a wear-resistant coating for copper shafts, gears, bearings, and other moving parts. Moreover, it can be used as a thermal barrier coating for copper heat exchangers or as a corrosion-resistant coating for copper pipelines. The versatility and feasibility of laser cladding
17、make it a promising technology for the surface modification of copper and other metallic materials.In addition to NiCrWB alloy, other materials can also be used for laser cladding on copper to enhance its properties. For example, ceramic materials, such as alumina, zirconia, and titanium dioxide, ca
18、n be used to improve the hardness and wear resistance of copper. Metals with high melting points, such as tungsten and molybdenum, can also be used to enhance the thermal resistance of copper.Another benefit of laser cladding is the possibility to create gradient layers, where the composition and mi
19、crostructure of the clad layer change gradually from the surface to the substrate. This can be achieved by adjusting the composition of the cladding material or by changing the laser power and speed during the process. Gradient layers can offer superior mechanical and physical properties compared to
20、 homogeneous layers. For example, a gradient layer with a high hardness on the surface and a tough substrate can provide both wear resistance and impact resistance.Laser cladding on copper can also be combined with other surface modification techniques, such as electroplating, to further improve the
21、 properties of the substrate. Multi-layered coatings with different materials and structures can be applied to achieve specific functionalities, such as improved friction, reduced adhesion, or enhanced biocompatibility.In conclusion, laser cladding can significantly improve the properties of copper
22、and expand its applications in various industries. The selection of cladding material, process parameters, and post-treatment can be optimized to achieve the desired properties of the clad layer. With the further development of laser technology and material science, laser cladding is expected to bec
23、ome a more versatile and efficient surface modification technique for metallic materials.One of the potential applications of laser-clad copper is in the manufacturing of electronic components, such as printed circuit boards (PCBs) and heat sinks. These components require high conductivity, low resi
24、stivity, and good thermal management properties. Copper is an ideal material for these applications, and laser cladding can further enhance these properties.Laser cladding can also be used to repair or refurbish worn-out copper components, such as molds, dies, and shafts. These components often suff
25、er from wear, corrosion, or fatigue, which can lead to costly downtime and replacement. Laser cladding can selectively deposit a layer of material on the damaged areas, restoring the original shape and function of the component. This can save time and money, as well as extend the lifespan of the com
26、ponent.Another potential application of laser-clad copper is in the aerospace industry, where lightweight and high-strength materials are in demand. Copper alloys with specific compositions can be laser-clad to achieve high tensile strength, corrosion resistance, and thermal stability. These propert
27、ies are important for various aerospace components, such as turbine blades, compressor disks, and fuel system parts.Furthermore, laser cladding can also be used to add functional features to copper components, such as anti-bacterial properties or self-lubrication. These features can be achieved by i
28、ncorporating specific additives, such as silver or graphite, into the cladding material. This can be useful for applications in the medical or automotive industry, where cleanliness and friction reduction are critical.In summary, laser cladding can offer a wide range of benefits for copper component
29、s, such as improved properties, enhanced functionality, and extended lifespan. The technology is continuously evolving, and new materials and applications are being explored. As a result, laser-clad copper is a promising field in materials science and surface engineering.Another potential applicatio
30、n of laser-clad copper is in the energy sector, where copper components are used in power generation and transmission. For example, laser cladding can produce high-performance copper contact parts for switches and breakers, which are critical for electrical safety and reliability. Additionally, lase
31、r cladding can enhance the corrosion resistance and wear resistance of copper busbars and connectors, which are crucial for efficient and stable current transmission.In the automotive industry, laser-clad copper can also be used for engine components, such as cylinder liners, pistons, and crankshaft
32、s. Copper alloys with specific chemical compositions and mechanical properties can improve the durability, efficiency, and emissions of internal combustion engines.Furthermore, laser-clad copper can be used in additive manufacturing processes, such as laser-based 3D printing, to produce complex geom
33、etries and custom designs of copper components. This can provide greater flexibility and efficiency compared to traditional manufacturing methods.In terms of research and development, laser-clad copper is a topic of interest for materials scientists and engineers. The technology allows for the study
34、 of the microstructure and properties of copper alloys at a high resolution, which can lead to insights into the fundamental principles of materials science.Overall, laser cladding technology offers numerous benefits for copper and copper alloys, making it a promising field for research and applicat
35、ion in various industries. The ability to tailor the properties and functionality of copper using laser cladding can lead to improved performance, increased efficiency, and reduced costs for many applications.Another potential application for laser-clad copper is in the electronics industry, where i
36、t can be used to produce components such as heat sinks, printed circuit boards, and connectors that require high thermal conductivity and electrical conductivity. Copper alloys can also be laser-clad onto non-conductive substrates, such as plastics or ceramics, to create conductive pathways for elec
37、tronic devices.Laser-clad copper can also be used in the aerospace industry to manufacture lightweight, high-performance components for aircraft and spacecraft. For example, copper-based alloys can be used to produce heat exchangers, radiators, and other components that require high thermal conducti
38、vity, corrosion resistance, and mechanical strength.Furthermore, laser-clad copper can be used to repair or replace damaged copper components, such as turbine blades, rotors, and stators, in power plants and other industrial settings. This can lead to cost savings and increased efficiency by avoidin
39、g the need for expensive replacements or downtime for repairs.In the medical industry, laser-clad copper can be used to produce implants or medical devices that require high biocompatibility and corrosion resistance. Copper alloys with specific chemical compositions and surface properties can improv
40、e the osteointegration of implants or the antimicrobial properties of medical devices.Finally, laser-clad copper can be used to upgrade or retrofit existing machinery and equipment by adding new features or improving performance. For example, copper coatings can be laser-clad onto worn or damaged ma
41、chine parts to restore their functionality and extend their lifespan.Overall, laser-clad copper offers a wide range of applications and potential benefits for numerous industries, from improving efficiency and reliability to reducing costs and increasing performance. The versatility and flexibility
42、of laser cladding technology make it a promising field for continued research and development to advance the capabilities and applications of copper and copper alloys.Another potential application of laser-clad copper is in the automotive industry, where copper coatings can be used to improve the pe
43、rformance and durability of engine components. Copper coatings can improve the heat dissipation of engine blocks and cylinder heads, leading to increased efficiency and reduced wear on engine internals.In the construction industry, laser-clad copper can be used to produce high-performance coatings f
44、or building facades, roofing materials, and other exterior applications. Copper coatings can improve corrosion resistance, energy efficiency, and aesthetic appeal, making them a popular choice for modern building designs.Another potential application of laser-clad copper is in the renewable energy i
45、ndustry, where copper coatings can be used to enhance the performance and longevity of solar panels, wind turbine components, and other renewable energy systems. Copper coatings can improve conductivity, durability, and resistance to environmental factors, such as saltwater exposure and extreme weat
46、her conditions.The food processing industry can also benefit from laser-clad copper coatings, which can improve the sanitary conditions of food processing equipment by reducing bacterial growth and improving resistance to corrosion.In the marine industry, laser-clad copper coatings can be used to im
47、prove the performance and durability of ship components, such as propellers, rudders, and hulls. Copper coatings can also reduce fuel consumption and carbon emissions by improving the efficiency and speed of ships.Overall, laser-clad copper has a wide range of potential applications in various indus
48、tries due to its high conductivity, corrosion resistance, and mechanical strength. As laser cladding technology continues to develop, it is likely that new applications and benefits of laser-clad copper will emerge.One of the key advantages of laser-clad copper is its ability to provide a thick, den
49、se coating with excellent adhesion properties. This makes it ideal for applications where a higher level of surface protection is needed. For example, copper coatings can be used on valves and pumps to prevent corrosion and ensure long-term reliability. Additionally, copper coatings can be applied to machinery components such as gears, bearings, and pistons to improve wear resistance and extend service life.Another area of application for laser-clad copper is in the aer
