A super-abrasion-resistant tungsten carbide particle reinforced weldable steel matrix composite material and a method of making the same

Abstract

This invention belongs to the field of metallurgical materials technology and relates to a composite material of weldable steel matrix reinforced with ultra-wear-resistant tungsten carbide particles and its preparation method. The method uses medium-carbon low-alloy steel of a specific composition as the matrix and tungsten carbide particles with a particle size of 4-6 mm as the wear-resistant reinforcing phase. The composite material is prepared through steps including sand mold preparation, directional particle laying, smelting and casting in an 1800℃ / 5h resistance furnace, temperature-controlled solidification and demolding, and segmented air-cooling hardening heat treatment. During the process, high temperature is used to achieve interfacial metallurgical bonding between the matrix and the tungsten carbide particles, forming a gradient transition layer. The wear-resistant layer of the composite material prepared by this invention exhibits improved Rockwell hardness, wear resistance, and interfacial shear strength, while also possessing excellent toughness and field weldability. The preparation process is mature, cost-controllable, and suitable for industrial mass production. It is applicable to wear-resistant parts for dredging equipment, significantly extending service life and reducing maintenance costs, and has extremely high engineering application value.

Description

Technical Field

[0001] This invention belongs to the field of metallurgical materials technology, and in particular relates to a composite material with ultra-wear-resistant tungsten carbide particle-reinforced weldable steel matrix and its preparation method. Background Technology

[0002] With the continuous advancement of underwater engineering projects such as port and waterway maintenance, submarine pipeline laying, and river dredging, cutter suction dredging technology has been widely adopted due to its high efficiency and adaptability. Cutter suction dredging equipment relies on the high-speed rotation of the cutter head to cut and break up underwater sediments or rock strata. Its key components, such as the cutter head frame, cutter teeth, and protective plates, are subjected to a harsh service environment of continuous scouring by sand and gravel and impact from various hard materials, along with the synergistic effects of corrosion and wear. Therefore, wear-resistant materials must be welded to the surface of these components for protection. Statistics show that a single large cutter suction dredger can consume up to several hundred kilograms of wear-resistant material per month (approximately 900-1500 wear blocks). The downtime caused by frequent replacement of wear blocks significantly increases dredging costs and reduces efficiency.

[0003] Current domestically produced wear-resistant materials (such as NM400) suffer from poor toughness and short wear life. Their wear patterns include impact fracture and hard phase abrasion, making them unsuitable for the demands of high-end wear-resistant blocks subjected to long-term high impact and heavy loads. Tungsten carbide, as a typical ultrahard wear-resistant material, possesses extremely high hardness and excellent resistance to abrasive wear, offering significant advantages in improving wear resistance. However, pure tungsten carbide or high-content tungsten carbide materials typically have poor toughness and are prone to brittle failure under frequent impact loads. Furthermore, their overall formability and weldability are limited, restricting their application in large or complex wear-resistant components. Therefore, achieving a balance between high wear resistance and good toughness and weldability to complement each other has become an important direction for the development of wear-resistant materials.

[0004] In recent years, composite wear-resistant materials have gradually attracted attention. Among them, the method of combining tungsten carbide reinforcing phase with steel matrix through casting is considered an effective way to achieve a balance between wear resistance, structural strength, and engineering manufacturing feasibility. However, existing composite cast wear-resistant materials still have shortcomings in terms of the uniformity of reinforcing phase distribution, interfacial metallurgical bonding strength, porosity defect control, and subsequent processing and welding performance. In particular, their overall performance needs to be further improved under high wear and high impact conditions.

[0005] Therefore, how to develop a protective material with excellent wear resistance, good impact resistance and reliable bonding strength to address the high wear and high impact characteristics of underwater operations such as cutter suction dredging and subsea engineering has become an urgent technical problem to be solved in the field of wear protection for key components of cutter suction dredging. Summary of the Invention

[0006] This invention provides a composite material of ultra-wear-resistant tungsten carbide particles reinforced with weldable steel matrix and its preparation method. The core of the invention lies in the metallurgical bonding of a weldable steel matrix with a specific composition design and ultra-wear-resistant tungsten carbide particles at the molten interface through a unique casting-infiltration composite process and gradient cooling heat treatment technology. This results in a material that macroscopically possesses excellent weldability, high toughness, and outstanding impact and wear resistance, and microscopically forms a continuous and dense tungsten carbide / steel matrix composite wear-resistant layer.

[0007] This invention is achieved through the following technical solution: A composite material with ultra-wear-resistant tungsten carbide particle-reinforced weldable steel matrix, wherein the steel matrix component comprises the following elements and their corresponding mass fractions: C: 0.25~0.45%, Mn: 0.60~1.20%, Si: 0.20~0.80%, Ni: 1.00~2.00%, Cr: 0.50~1.50%, Mo: 0.15~0.35%, Cu: 0.35~0.55%, with the balance being Fe. The raw materials for ultra-wear-resistant tungsten carbide particles are tungsten trioxide and carbon black. Tungsten carbide is generated by the carbothermic reduction reaction of tungsten trioxide with carbon at high temperature.

[0008] This invention also proposes a method for preparing a composite material with ultra-wear-resistant tungsten carbide particles reinforced weldable steel matrix, the method comprising the following steps: Step 1: Prepare the sand mold cavity; a wet sand mold is made by mixing silica sand, bentonite and water in a certain proportion. The mixed wet sand mold is filled into the mold, and it is compacted by tamping, squeezing and vibrating to form a precise cavity. The mold is then removed, leaving the sand mold cavity. Step 2: Place tungsten carbide particles; precisely and evenly place ultra-wear-resistant hard tungsten carbide alloy particles into specific areas of the sand mold cavity; Step 3: Molten steel; The raw materials corresponding to the elements of the steel base components mentioned above are introduced into the resistance melting furnace for melting treatment according to the proportion. The resistance melting furnace is heated and stirred. The heating temperature of the resistance melting furnace is 1200℃-1900℃, and the melting time is controlled at 4~6 hours. During the melting process, the rotation of the resistance melting furnace allows the internal metal solution to achieve full fusion treatment, resulting in molten steel. Step 4: Pouring molten steel; The molten steel is poured smoothly into the sand mold cavity where tungsten carbide particles have been placed. The molten steel and the surface of the tungsten carbide particles dissolve into each other. At the same time, the high temperature promotes the diffusion of carbon elements at the interface, thereby forming a narrow transition layer with gradually changing composition. Step 5, Demolding after solidification; After pouring, the casting enters the solidification and cooling stage. When the casting temperature drops to 850~950℃, the casting is completely solidified. Use an air compressor to break the sand mold, remove the casting body, shot blast to clean off the surface sand and oxide scale, and use a grinding wheel to remove the gating and riser. Step six involves using segmented heating and graded air cooling to harden the material, resulting in an ultra-wear-resistant composite material.

[0009] Compared with the prior art, the technical solution proposed in this invention brings the following significant beneficial effects: 1. A breakthrough combination of ultra-strong wear resistance, high density and high homogeneity of wear-resistant layer is achieved: Through a unique casting-infiltration composite process and gradient cooling heat treatment technology, a weldable steel base with a specific composition design and ultra-wear-resistant tungsten carbide particles are metallurgically bonded at the molten interface. The ultra-wear-resistant tungsten carbide particles are uniformly and tightly embedded in the steel base. This wear-resistant layer has extremely high hardness and wear resistance. Moreover, due to its strong bonding and dense structure (porosity ≤3%), it can remain stable for a long time under high impact and wear conditions, which can significantly improve dredging efficiency. 2. Achieving synergistic optimization between high toughness and good weldability of materials: In the preparation and processing of wear-resistant materials, the steel-based material and the ultra-wear-resistant tungsten carbide wear-resistant layer are metallurgically bonded. At the same time, the composition of the steel-based material and the gradient of the optimized air cooling are precisely controlled, achieving a good balance between good toughness and outstanding weldability. This solves the contradiction that high-hardness materials are usually difficult to weld or have high brittleness. The resulting composite material has an impact toughness Kv > 40J. The mounting surface of its steel-based part can be connected to the equipment base material through conventional welding to achieve a high-strength, crack-free, and reliable connection, which significantly improves the convenience of replacing and maintaining wear-resistant parts. Attached Figure Description

[0010] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 The present invention provides a process flow diagram for preparing a composite material with ultra-wear-resistant tungsten carbide particle-reinforced weldable steel matrix; Figure 2 Microstructure diagram of the composite material prepared using the method proposed in this invention; Figure 3 The image shows a physical sample of the composite material prepared using the method proposed in this invention. Detailed Implementation

[0012] In the following description, specific details such as particular system architectures and technologies are set forth for illustrative purposes and not for limiting purposes, so as to provide a thorough understanding of the embodiments of the present invention.

[0013] This invention proposes a composite material with a weldable steel matrix reinforced with ultra-wear-resistant tungsten carbide particles. The steel matrix composition includes the following elements and their corresponding mass fractions: C: 0.25~0.45%, Mn: 0.60~1.20%, Si: 0.20~0.80%, Ni: 1.00~2.00%, Cr: 0.50~1.50%, Mo: 0.15~0.35%, Cu: 0.35~0.55%, with the balance being Fe. The raw materials for ultra-wear-resistant tungsten carbide particles are tungsten trioxide and carbon black. Tungsten carbide is generated by the carbothermic reduction reaction of tungsten trioxide with carbon at high temperature.

[0014] like Figure 1 As shown, this invention proposes a method for preparing a composite material with ultra-wear-resistant tungsten carbide particle-reinforced weldable steel matrix, the preparation method comprising the following steps: Step 1: Prepare the sand mold cavity; a wet sand mold is made by mixing silica sand, bentonite and water in a certain proportion. The mixed wet sand mold is filled into the mold, and it is compacted by tamping, squeezing and vibrating to form a precise cavity. The mold is then removed, leaving the sand mold cavity. Step 2: Place tungsten carbide particles; precisely and evenly place ultra-wear-resistant hard tungsten carbide alloy particles into specific areas of the sand mold cavity; Step 3: Molten steel; The raw materials corresponding to the elements of the steel base components mentioned above are introduced into the resistance melting furnace for melting treatment according to the proportion. The resistance melting furnace is heated and stirred. The heating temperature of the resistance melting furnace is 1200℃-1900℃, and the melting time is controlled at 4~6 hours. During the melting process, the rotation of the resistance melting furnace allows the internal metal solution to achieve full fusion treatment, resulting in molten steel. Step 4: Pouring molten steel; The molten steel is poured smoothly into the sand mold cavity where tungsten carbide particles have been placed. The molten steel and the surface of the tungsten carbide particles dissolve into each other. At the same time, the high temperature promotes the diffusion of carbon elements at the interface, thereby forming a narrow transition layer with gradually changing composition. Step 5, Demolding after solidification; After pouring, the casting enters the solidification and cooling stage. When the casting temperature drops to 850~950℃, the casting is completely solidified. Use an air compressor to break the sand mold, remove the casting body, shot blast to clean off the surface sand and oxide scale, and use a grinding wheel to remove the gating and riser. Step six involves using segmented heating and graded air cooling to harden the material, resulting in an ultra-wear-resistant composite material.

[0015] In step one, the mass proportion of silica sand is 85-90%, the mass proportion of bentonite is 6-10%, and the mass proportion of water is 3-5%. The dimensions of the template in step one need to be determined by design calculation based on the final dimensions of the target wear-resistant block, taking into account the solidification shrinkage rate of the metal alloy and the machining allowance reserved on each surface. In step two, the diameter of the ultra-wear-resistant hard tungsten carbide alloy particles is 4-6 mm. Particles of different diameters correspond to different properties and application conditions of wear-resistant castings. Large particles can provide extremely strong impact resistance and resistance to macroscopic cutting. Medium particles balance wear resistance and the matrix's gripping force on the particles. Fine particles can provide a denser and smoother wear-resistant surface, reduce slurry flow resistance, and effectively resist microscopic cutting and corrosion by fine abrasive particles. Specific areas and tungsten carbide alloy particles can be selected and laid according to the actual application.

[0016] Specifically, in step six, after the casting is demolded, it is placed in a preheated furnace at 880°C for 30-60 minutes. Then, the furnace temperature is increased from 880°C to the target austenitizing temperature of 910-930°C at a rate of 1-2°C / minute. After reaching this temperature, it is held at this temperature for 4 hours. Subsequently, the casting is placed on a dry surface without strong convection, and a high-power axial flow fan is used to blow air onto the casting. The cooling rate is controlled by adjusting parameters such as wind speed, wind temperature, and wind direction. First, it is cooled to 700-900°C at a rate of 5°C / minute, and then cooled to 200-250°C at a rate of 50°C / minute. Finally, under the cover of insulation material, it is cooled to room temperature at a rate of less than 0.5°C / hour, resulting in an ultra-wear-resistant composite material with a uniform, compact, and non-porous layer of ultra-wear-resistant tungsten carbide.

[0017] In a specific embodiment of this invention, a composite material made of ultra-wear-resistant tungsten carbide particles reinforced with weldable steel is used as an example, and this material is made into a rectangular plate-shaped wear-resistant block with dimensions of 200mm × 80mm × 25mm. This wear-resistant block can be used as a long strip-shaped liner to protect the edges of the cutter head: Prepare raw materials for the steel base composition including the following elements and mass components: C: 0.25~0.45%, Mn: 0.60~1.20%, Si: 0.20~0.80%, Ni: 1.00~2.00%, Cr: 0.50~1.50%, Mo: 0.15~0.35%, Cu: 0.35~0.55%, with the balance being Fe. Preparation of ultra-wear-resistant tungsten carbide particles: Tungsten trioxide is reduced with carbon black at 1100℃ to remove all oxygen, producing a mixture of tungsten, tungsten dicarbide and tungsten carbide. Then a certain amount of carbon black is added to the prepared mixture, and the sample is carburized at 1200℃ in a hydrogen atmosphere to prepare tungsten carbide particles. The composite material was then prepared according to the following steps: Step 1: Preparing the sand mold cavity: Mix 87% silica sand, 8% bentonite and 5% water in a certain proportion to form a wet sand mold. Fill the mold with the mixed wet sand mold, and compact it by tamping, squeezing and vibrating to form a precise cavity. Remove the mold and leave the sand mold cavity. Step 2: Place tungsten carbide particles: Precisely and evenly place the prepared 4-6mm ultra-wear-resistant hard tungsten carbide alloy particles into the specific area in the sand mold cavity where a wear-resistant layer needs to be formed, with a thickness of 7.5mm. Step 3: Molten Steel: The raw materials corresponding to the elements of the steel base components mentioned above are introduced into the resistance melting furnace for melting treatment according to the proportion. The resistance melting furnace is heated and stirred. The heating temperature of the resistance melting furnace is 1800℃, and the melting time is controlled at 5 hours. During the melting process, the rotation of the resistance melting furnace allows the internal metal solution to achieve full fusion treatment to obtain molten steel. Step 4: Pouring molten steel: Pour the molten steel smoothly into the sand mold cavity where tungsten carbide particles have been placed. The molten steel and the surface of the tungsten carbide particles will dissolve into each other. At the same time, the high temperature will cause carbon elements to diffuse at the interface, thus forming a narrow transition layer with a gradual change in composition. Step 5: Demolding after solidification: After pouring, the casting enters the solidification and cooling stage. When the casting temperature drops to 850~950℃, the casting is completely solidified. Use an air compressor to break the sand mold, remove the casting body, shot blast to clean off the surface sand and oxide scale, and use a grinding wheel to remove the gating and riser. Step Six: Air Cooling Hardening: After demolding, the casting is placed in a preheated furnace at 880°C for 30-60 minutes. The furnace temperature is then increased from 880°C to the target austenitizing temperature of 910-930°C at a rate of 1-2°C / minute. Once this temperature is reached, it is held at this temperature for 4 hours. Subsequently, the casting is placed on a dry surface without strong convection, and a high-power axial flow fan is used to blow air onto it. The cooling rate is controlled by adjusting parameters such as wind speed, temperature, and direction. First, it is cooled to 700-900°C at a rate of 5°C / minute, then to 200-250°C at a rate of 50°C / minute. Finally, it is covered with a ceramic fiber blanket and cooled to room temperature at a rate of less than 0.5°C / hour. The final product is a 200mm × 80mm × 25mm ultra-wear-resistant composite material with a uniform, compact, and non-porous layer of ultra-wear-resistant tungsten carbide.

[0018] like Figure 2 As shown, Figure 2The image shows the microstructure of the composite material prepared using the method proposed in this invention. It can be seen that after shot blasting and grinding, the wear-resistant layer thickness of the casting is stable, and the tungsten carbide particles are evenly distributed and tightly arranged, without any agglomeration or accumulation. X-ray flaw detection and visual inspection show that the casting has no internal pores, cracks, or inclusions, and the surface has no sand residue. The forming accuracy meets the requirements for machining and assembly of wear-resistant blocks. Figure 3 This is a photograph of the finished composite material obtained through the preparation process.

[0019] Performance tests were conducted on the finished wear-resistant block with a diameter of 200mm × 80mm × 25mm. Three sets of samples were prepared in parallel before the test, and the average value was taken as the final result. The test items are as follows: Hardness testing is used to verify the hardness difference between the wear-resistant layer of the composite material and the steel matrix, using Rockwell and Brinell hardness as evaluation standards. Mechanical property testing is used to detect the tensile strength and impact toughness of composite materials, adapting to the impact and stress conditions of dredging operations; Density testing was conducted using the water displacement method to verify that the composite castings were free of defects such as porosity and looseness. Wear resistance test is used to simulate wet abrasive wear of mud and compare it with traditional high manganese steel liner for dredging to quantify the wear resistance improvement effect of composite materials. Interfacial bonding performance test: Test the interfacial shear strength between tungsten carbide particles and steel matrix to evaluate the metallurgical bonding effect. Microscopic characterization tests were conducted using metallographic microscopy, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) to observe the particle arrangement, interfacial transition layer and element diffusion patterns of the composite material. The test results are shown in Table 1 below.

[0020] Table 1. Test results of composite material properties

[0021] In the simulation of mud working conditions on a cutter suction dredger, 0.5~1.0mm quartz sand was selected as the abrasive, with a solid-liquid ratio of 1:1, an applied load of 50N, an abrasion speed of 200r / min, and a total abrasion time of 120min. The results were compared with those of ordinary high-manganese steel liners commonly used in the dredging industry. In this embodiment, the wear resistance of the composite material wear-resistant layer is 0.83~0.96 mg / cm². 2 The wear rate per unit area of ​​ordinary high-manganese steel lining plates is 3.27~3.59 mg / cm². 2 Therefore, it can be seen that, based on high-manganese steel, the wear resistance of this composite material is greatly improved; and in the impact wear test, it withstood an impact energy of 5J and 10... 4After the impact, the wear-resistant layer showed no tungsten carbide particles falling off or macroscopic cracks, only slight uniform wear marks; the high-manganese steel sample showed obvious plastic deformation and deep groove wear.

[0022] Metallographic microscopy revealed a continuous and dense transition layer between the tungsten carbide particles and the steel matrix, with a stable layer width; no interface gaps, pores, or microcracks were observed. The steel matrix structure consisted of tempered martensite plus a small amount of retained austenite, ensuring both matrix strength and sufficient toughness; the tungsten carbide particles exhibited intact morphology, without high-temperature burn-off or excessive dissolution, and the wear-resistant phase remained intact.

[0023] Manual arc welding tests were conducted using low-hydrogen alloy structural steel welding rods. The welds showed no defects such as porosity, cracks, or lack of fusion. The heat-affected zone of the welds did not exhibit significant hardness drops or embrittlement, meeting the requirements for on-site welding and assembly of the cutter head liner plates of cutter suction dredgers, as well as subsequent maintenance and repair welding.

[0024] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0025] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0026] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A method for preparing a composite material with ultra-wear-resistant tungsten carbide particle-reinforced weldable steel matrix, characterized in that, The preparation method includes the following steps: Step 1: Prepare the sand mold cavity; a wet sand mold is made by mixing silica sand, bentonite and water in a certain proportion. The mixed wet sand mold is filled into the mold, and it is compacted by tamping, squeezing and vibrating to form a cavity. The mold is then removed, leaving the sand mold cavity. Step 2: Place tungsten carbide particles; place ultra-wear-resistant hard tungsten carbide alloy particles into a specific area of ​​the sand mold cavity; Step 3: Molten steel; Raw materials with corresponding elements of the steel base composition are introduced into an electric resistance melting furnace for melting treatment to obtain molten steel; The steel base composition is C: 0.25~0.45%, Mn: 0.60~1.20%, Si: 0.20~0.80%, Ni: 1.00~2.00%, Cr: 0.50~1.50%, Mo: 0.15~0.35%, Cu: 0.35~0.55%, with the balance being Fe; Step 4: Pouring molten steel; The molten steel is poured into the sand mold cavity where tungsten carbide particles have been placed. The molten steel and the surface of the tungsten carbide particles dissolve into each other, and the high temperature causes carbon elements to diffuse at the interface to form a transition layer. Step 5, Demolding after solidification; After pouring, the casting enters the solidification and cooling stage. After the casting has completely solidified, the sand mold is destroyed by an air compressor, the casting body is removed, the surface sand and oxide scale are removed by shot blasting, and the gating gate is removed by grinding with a grinding wheel. Step six involves using segmented heating and graded air cooling to harden the material, resulting in an ultra-wear-resistant composite material.

2. In the method for preparing composite materials according to claim 1, in step one, the mass proportion of silica sand is 85-90%, the mass proportion of bentonite is 6-10%, and the mass proportion of water is 3-5%.

3. In the composite material preparation method according to claim 1, in step one, the size of the template is determined by design calculation based on the final size of the target wear-resistant block, taking into account the solidification shrinkage rate of the metal alloy and the machining allowance reserved on each surface.

4. In the method for preparing composite materials according to claim 1, in step two, the diameter of the ultra-wear-resistant hard tungsten carbide alloy particles is 4~6 mm.

5. The composite material preparation method according to claim 1, wherein in step six, the air cooling hardening method using segmented heating and graded air cooling specifically comprises: After the casting is demolded, it is placed in a preheated furnace at 880°C for 30-60 minutes. Then, the furnace temperature is increased from 880°C to the target austenitizing temperature of 910-930°C at a rate of 1-2°C / minute. After reaching this temperature, it is held at this temperature for 4 hours. Subsequently, the casting is placed on a dry surface without strong convection, and a high-power axial flow fan is used to blow air onto the casting. The cooling rate is controlled by adjusting the wind speed, wind temperature and wind direction parameters.

6. The method for preparing the composite material according to claim 5, wherein the controlled cooling rate is as follows: first, cooling to 700~900℃ at a rate of 5℃ / min, then cooling to 200~250℃ at a rate of 50℃ / min; finally, under the cover of the heat-insulating material, cooling to room temperature at a rate of less than 0.5℃ / hour, and finally obtaining an ultra-wear-resistant composite material with a uniform, compact, and non-porous layer of ultra-wear-resistant tungsten carbide.

7. The method for preparing composite materials according to claim 1, wherein the ultra-wear-resistant tungsten carbide particles are prepared by: reducing tungsten trioxide with carbon black at 1100°C to remove all oxygen, producing a mixture of tungsten, tungsten dicarbide and tungsten carbide, then adding a certain amount of carbon black to the prepared mixture, and carburizing the sample at 1200°C under a hydrogen atmosphere to prepare tungsten carbide particles.

8. The composite material prepared by the composite material preparation method according to any one of claims 1-7, wherein the steel matrix component of the composite material comprises the following elements and their corresponding mass components: C: 0.25~0.45%, Mn: 0.60~1.20%, Si: 0.20~0.80%, Ni: 1.00~2.00%, Cr: 0.50~1.50%, Mo: 0.15~0.35%, Cu: 0.35~0.55%, with the balance being Fe; The raw materials for ultra-wear-resistant tungsten carbide particles are tungsten trioxide and carbon black. Tungsten carbide is generated by the carbothermic reduction reaction of tungsten trioxide with carbon at high temperature.

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