A method of producing wear resistant components from cemented carbide wear testing scrap

Abstract

The application discloses a method for preparing wear-resistant components from hard alloy wear resistance test waste, and belongs to the technical field of hard alloy preparation. The method is aimed at wear resistance test mixed waste containing WC-Co hard alloy particles, alumina abrasive and steel chips, and adopts an integrated process of in-situ morphology reservation, magnetic and gas coupling separation and low-temperature sintering. First, most of the steel chips are removed through magnetic separation, and then demagnetization treatment is performed to eliminate the magnetic agglomeration of residual steel chips, and then the alumina is accurately separated by using the density difference through air classification, and the natural grinding corner morphology of the WC-Co particles is completely reserved without crushing and ball milling. The separated WC-Co grinding material is directly mixed with metal matrix powder, cold-pressed into a shape, and then low-temperature sintering is performed in a protective atmosphere to obtain high-performance wear-resistant components. The method has a short process flow, low energy consumption, and no chemical reagents such as acid and alkali are used throughout the process, so that pollutant emission is almost zero, and the method has cost advantages and environmental benefits.

Description

Technical Field

[0001] This invention relates to the field of cemented carbide preparation technology, and in particular to a method for preparing wear-resistant components from cemented carbide wear resistance test waste. Background Technology

[0002] In the production and application of cemented carbide, rigorous wear resistance testing is required to ensure product quality. This process generates a large amount of mixed waste containing WC-Co cemented carbide, alumina abrasive, and 20 steel fragments. Currently, the treatment methods for this specific waste mainly focus on tungsten extraction and recovery, which suffers from complex processes, high energy consumption, high costs, and secondary pollution, and fails to fully utilize the inherent wear-resistant properties of WC-Co particles in the waste. Furthermore, while existing technologies offer insights into WC-Co recycling and the preparation of wear-resistant components using nickel-copper alloys, they do not specifically design processes for the unique characteristics of wear resistance testing waste. Additionally, the conventional WC-Co sintering temperature is 1300~1500℃, resulting in high energy consumption and a tendency to cause grain coarsening.

[0003] Currently, the treatment methods for this type of specific waste have significant shortcomings and have not been effectively resolved for a long time. First, the WC-Co particles in the waste have formed a natural grinding angular morphology after being ground and impacted during the testing process. This morphology is characterized by a small radius of curvature, a large specific surface area, and sharp edges, which have a stronger mechanical meshing potential with the metal matrix compared to regular spherical particles. However, in pursuit of high recovery rates, traditional recycling methods usually employ a powerful mechanical path combining crushing, screening, and magnetic separation. Although this method can separate some impurities, it completely destroys the natural grinding angular morphology of the WC-Co particles, causing the particles to tend to become spherical. This leads to a decrease in the bonding force with the metal matrix, requiring the addition of additional bonding promoters, increasing costs and affecting performance stability. Second, existing pretreatment methods mostly use single magnetic separation or single airflow classification, without considering the interference of magnetic agglomeration of residual steel chips after magnetic separation on airflow classification. For example, magnetic separation alone cannot remove fine steel shavings (<100μm), and the magnetic agglomeration of residual steel shavings will cause WC-Co particles to settle together with the steel shavings in the air classifier, resulting in a decrease in WC-Co purity. Air classifier alone cannot distinguish between magnetic steel shavings and non-magnetic alumina, resulting in insufficient separation selectivity. In addition, this type of waste contains high-density WC-Co, medium-density steel shavings, and low-density alumina. The three have significant density differences but overlapping particle size distributions, making it difficult for traditional single separation methods to achieve accurate separation. When treating this type of waste, the effect is far from meeting the requirements of industrial applications.

[0004] Therefore, developing a technology that can preserve the in-situ advantageous morphology of WC-Co in waste materials, eliminate magnetic interference through multi-method synergistic pretreatment, efficiently and accurately separate impurities, and achieve low-temperature sintering to prepare high-performance wear-resistant components has become an urgent need in the industry. Summary of the Invention

[0005] This invention aims to overcome the shortcomings of existing technologies and provide a method that is simple in process, low in cost, low in pollution, and can realize the high-value utilization of waste materials from cemented carbide wear resistance testing. The method provided by this invention can achieve efficient and precise removal of steel chips and alumina while completely preserving the natural grinding angular morphology of WC-Co particles. At the same time, it eliminates the interference of magnetic agglomeration of residual steel chips after magnetic separation on the accuracy of airflow classification. Furthermore, it achieves the densification and sintering of WC-Co grinding material and metal matrix under low temperature conditions, without the need for binder accelerators, and directly prepares high-performance wear-resistant components. Ultimately, it achieves the dual goals of efficient recycling of tungsten resources and high-value utilization of products.

[0006] This invention targets a mixed waste material for wear resistance testing containing WC-Co cemented carbide particles, alumina abrasive, and steel chips. It employs an integrated process of in-situ morphology preservation, magnetic coupling separation, and low-temperature sintering. Through multi-step physical separation and synergy, the natural advantageous morphology of WC-Co particles in the waste material is fully preserved, and high-performance wear-resistant components are directly prepared.

[0007] The technical solution of this invention is as follows: This invention provides a method for preparing wear-resistant components from cemented carbide wear resistance test waste, comprising the following steps: S1. After drying the waste material from the cemented carbide wear resistance test, it is sieved to obtain the first-grade material. S2. Perform magnetic separation on the primary material to obtain the magnetically separated material; S3. The magnetically separated material is demagnetized at 300~400℃ to obtain the material to be classified. S4. The material to be classified is subjected to airflow classification treatment. The airflow velocity of the airflow classification treatment is 1.2~1.8m / s, the classification wheel speed is 2000~3500rpm, and the negative pressure of the classification chamber is -800~-500Pa to obtain WC-Co abrasive material. S5. Mix the WC-Co abrasive with the metal matrix powder to obtain wear-resistant aggregate; S6. The wear-resistant aggregate is cold-pressed into a green blank of a wear-resistant component; S7. The wear-resistant component green blank is sintered under an inert protective atmosphere to obtain the finished wear-resistant component; The method does not include a crushing step or a ball milling step.

[0008] Preferably, in step S1, the cemented carbide wear resistance test waste contains WC-Co cemented carbide particles, alumina abrasive particles, and steel chips, wherein the steel chips are 20 steel chips.

[0009] Preferably, the WC-Co cemented carbide particles have a grinding angular morphology naturally formed during the wear resistance testing process.

[0010] Further explanation of this invention: This invention identifies and utilizes the natural grinding angular morphology of WC-Co particles in cemented carbide wear resistance test waste. Contrary to the common prior art approach of crushing followed by recycling, this invention deliberately avoids any crushing or ball milling operations throughout the entire process, fully preserving the sharp, multi-faceted original structure of the WC-Co particles. This structure can mechanically engage with the metal matrix during subsequent cold pressing and sintering, replacing the role of traditional binder accelerators and significantly enhancing the bonding strength with the metal matrix.

[0011] Preferably, in step S2, the magnetic field strength of the magnetic separation process is 0.8~1.2T.

[0012] Preferably, in step S3, the demagnetization time for the demagnetization process is 30-60 minutes.

[0013] Preferably, in step S4, the feed rate of the airflow classification is 10~30 kg / h.

[0014] Further explanation of this invention: This invention employs a demagnetization process at a specific temperature of 300-400°C as a necessary operational step between magnetic separation and air classification. This differs from the independent or simple series combination of magnetic separation and air classification in existing technologies, solving the problem of magnetic agglomeration of residual steel chips after magnetic separation. The demagnetization step ensures that the material is not affected by magnetic interference during subsequent air classification, thereby achieving efficient and high-precision separation of WC-Co, steel chips, and alumina in complex abrasion resistance test waste, yielding high-purity WC-Co abrasive material.

[0015] Preferably, in step S5, 70-90% of WC-Co abrasive and 10-30% of metal matrix powder are weighed by mass percentage and mixed at a speed of 30-50 rpm for 30-60 min.

[0016] Preferably, the metal matrix powder is copper powder, nickel powder, or a mixture of copper and nickel powder, with a particle size of 50~150μm.

[0017] Preferably, the copper-nickel mixed powder is composed of copper powder and nickel powder in a mass ratio of (3~5):(1~4).

[0018] Preferably, in step S6, the pressure of cold pressing is 15~25MPa, and the holding time is 30~60s.

[0019] Preferably, in step S7, the inert protective atmosphere is argon or nitrogen.

[0020] Preferably, in step S7, the sintering heating rate is 8~12℃ / min, the sintering temperature is 800~900℃, and the holding time is 60~120min.

[0021] Further explanation of the present invention: The present invention utilizes the high surface activity of ground WC-Co particles, combined with the liquid phase sintering characteristics of copper / nickel low-melting-point matrix, to achieve densification at 800℃~900℃, which is much lower than the conventional WC-Co sintering temperature (1300℃~1500℃). This not only significantly reduces energy consumption, but also effectively inhibits the excessive growth of WC grains and optimizes the overall mechanical properties of the material.

[0022] Preferably, in step S7, the finished wear-resistant component has a hardness HV30 ≥ 1250 and an impact toughness ≥ 10.8 J / cm. 2 Density ≥89.5%.

[0023] The beneficial effects of this invention are as follows: 1. Compared with the prior art, the present invention provides a method for preparing wear-resistant components from cemented carbide wear resistance test waste. It clearly proposes and realizes the complete preservation of the natural angular morphology of WC-Co particles in the wear resistance test waste. This morphology enables the particles to produce a mechanical interlocking and anchoring effect with the copper / nickel metal matrix that is far greater than that of conventional spherical particles when they act as a reinforcing phase. This endows the wear-resistant components with excellent intrinsic bonding strength from the source, so that no exogenous bonding accelerators need to be added. This not only simplifies the batching system and reduces costs, but also avoids the adverse effects of bonding accelerators on performance stability.

[0024] 2. The method of this invention employs a pretreatment process that combines magnetic separation, demagnetization, and airflow classification in a sequential and coordinated manner. Magnetic separation initially removes macroscopic 20 steel chips. The subsequent demagnetization operation uses heating at 300-400°C to eliminate residual magnetism in the fine steel chips after magnetic separation, preventing the magnetically charged chips from agglomerating or adhering to the WC-Co particle surface, which could hinder effective separation in subsequent airflow classification. After demagnetization eliminates magnetic agglomeration interference, airflow classification is performed. Utilizing the density and morphology differences among WC-Co, alumina, and residual steel chips, high-precision separation is achieved by precisely controlling the airflow speed and classification wheel speed. The method provided by this invention not only achieves efficient and precise removal of steel chips and alumina impurities, resulting in high-purity WC-Co grinding material with good particle integrity, but also eliminates the acid dissolution, purification, and particle reprocessing steps of traditional tungsten recovery. The process is short, energy-efficient, and uses no acid or alkali chemicals, resulting in almost zero pollutant emissions, combining cost advantages with environmental benefits.

[0025] 3. Compared with existing technologies, this invention designs a process specifically for the composition and characteristics of cemented carbide wear resistance test waste. It utilizes the high surface activity of ground WC-Co particles, combined with the low-temperature liquid-phase sintering characteristics of the copper-nickel matrix, to achieve densification sintering at a lower temperature. The resulting wear-resistant components have high density and a good balance between hardness and toughness. This invention specifically addresses the industry pain point of low resource utilization of this type of waste, demonstrating strong adaptability and high recycling efficiency. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, 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 this application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0027] Figure 1 This is a SEM image of the WC-Co abrasive material prepared in Example 1 of this application.

[0028] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0029] The technical solutions described below in conjunction with the embodiments will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] This invention provides a method for preparing wear-resistant components from cemented carbide wear resistance test waste, comprising the following steps: S1. After drying the waste material from the cemented carbide wear resistance test, it is sieved to obtain the first-grade material. S2. Perform magnetic separation on the primary material to obtain the magnetically separated material; S3. The magnetically separated material is demagnetized at 300~400℃ to obtain the material to be classified. S4. The material to be classified is subjected to airflow classification treatment. The airflow velocity of the airflow classification treatment is 1.2~1.8m / s, the classification wheel speed is 2000~3500rpm, and the negative pressure of the classification chamber is -800~-500Pa to obtain WC-Co abrasive material. S5. Mix the WC-Co abrasive with the metal matrix powder to obtain wear-resistant aggregate; S6. The wear-resistant aggregate is cold-pressed into a green blank of a wear-resistant component; S7. The wear-resistant component green blank is sintered under an inert protective atmosphere to obtain the finished wear-resistant component; The method does not include a crushing step or a ball milling step.

[0031] Preferably, in step S1, the cemented carbide wear resistance test waste contains WC-Co cemented carbide particles, alumina abrasive particles, and steel chips, wherein the steel chips are 20 steel chips.

[0032] Preferably, the WC-Co cemented carbide particles have a grinding angular morphology naturally formed during the wear resistance testing process.

[0033] Preferably, in step S1, the product is dried and then passed through a 10-20 mesh sieve.

[0034] Preferably, in step S2, the magnetic field strength of the magnetic separation process is 0.8~1.2T; Specifically, the magnetic field strength can be any one of 0.8T, 0.9T, 1.0T, 1.1T, 1.2T, or a range between any two.

[0035] Preferably, in step S3, the demagnetization time for the demagnetization process is 30-60 minutes; Specifically, the demagnetizing temperature of the demagnetizing process can be any one or a range between any two of 300℃, 320℃, 340℃, 350℃, 360℃, 380℃, and 400℃; the demagnetizing time can be any one or a range between any two of 30min, 35min, 40min, 45min, 50min, 55min, and 60min.

[0036] Preferably, in step S4, the feed rate of the airflow classification is 10~30 kg / h; Specifically, the airflow velocity for air classification can be any one or a range between any two of 1.2 m / s, 1.3 m / s, 1.4 m / s, 1.5 m / s, 1.6 m / s, 1.7 m / s, and 1.8 m / s; the classification wheel rotation speed can be any one or a range between any two of 2000 rpm, 2200 rpm, 2400 rpm, 2500 rpm, 2600 rpm, 2800 rpm, 3000 rpm, 3200 rpm, and 3500 rpm; the classification chamber negative pressure can be any one or a range between any two of -800 Pa, -750 Pa, -700 Pa, -650 Pa, -600 Pa, -550 Pa, and -500 Pa; and the feed rate can be any one or a range between any two of 10 kg / h, 15 kg / h, 20 kg / h, 25 kg / h, and 30 kg / h.

[0037] Preferably, in step S5, 70-90% of WC-Co abrasive and 10-30% of metal matrix powder are weighed by mass percentage and mixed at a speed of 30-50 rpm for 30-60 min. Specifically, the mass percentage of the WC-Co abrasive can be any one or a range between 70%, 75%, 80%, 85%, and 90%; the mass percentage of the metal matrix powder can be any one or a range between 10%, 15%, 20%, 25%, and 30%; the rotational speed can be any one or a range between 30 rpm, 35 rpm, 40 rpm, 45 rpm, and 50 rpm; and the mixing time can be any one or a range between 30 min, 35 min, 40 min, 45 min, 50 min, 55 min, and 60 min.

[0038] Preferably, the metal matrix powder is copper powder, nickel powder, or a mixture of copper and nickel powder, with a particle size of 50~150μm.

[0039] Preferably, the copper-nickel mixed powder is composed of copper powder and nickel powder in a mass ratio of (3~5):(1~4).

[0040] Preferably, in step S6, the pressure of the cold pressing is 15~25MPa, and the holding time is 30~60s; Specifically, the pressure for cold pressing can be any one or a range between 15MPa, 18MPa, 20MPa, 22MPa, and 25MPa; the holding time can be any one or a range between 30s, 35s, 40s, 45s, 50s, 55s, and 60s.

[0041] Preferably, in step S7, the inert protective atmosphere is argon or nitrogen.

[0042] Preferably, in step S7, the sintering heating rate is 8~12℃ / min, the sintering temperature is 800~900℃, and the holding time is 60~120min; Specifically, the sintering heating rate can be any one of 8℃ / min, 10℃ / min, 12℃ / min, or any combination thereof; the demagnetizing temperature can be any one of 800℃, 820℃, 840℃, 850℃, 860℃, 880℃, 900℃, or any combination thereof; and the demagnetizing time can be any one of 60min, 70min, 80min, 90min, 100min, 110min, 120min, or any combination thereof.

[0043] Preferably, in step S7, the finished wear-resistant component has a hardness HV30 ≥ 1250 and an impact toughness ≥ 10.8 J / cm. 2 Density ≥89.5%.

[0044] In a preferred embodiment, the method for preparing wear-resistant components from cemented carbide wear resistance test waste includes the following steps: S1. Place the cemented carbide wear resistance test waste in a drying oven to remove moisture. After drying, pass the waste through a 10-20 mesh standard sieve to obtain first-grade material. S2. Perform magnetic separation on the primary material with a magnetic field strength of 0.8~1.2T to obtain the magnetically separated material; S3. Place the magnetically separated material in a tube furnace and demagnetize it at 300~400℃ for 30~60 minutes. After demagnetization, cool it naturally to room temperature to obtain the material to be classified. S4. Add the material to be classified into the feeding device of the air classifier for separation. Set the airflow velocity to 1.2~1.8m / s, the classifier wheel speed to 2000~3500rpm, the feed rate to 10~30kg / h, and the negative pressure of the classifier chamber to -800~-500Pa to obtain WC-Co grinding material. S5. Weigh 70-90% of WC-Co abrasive and 10-30% of metal matrix powder with a particle size of 50-150μm by mass percentage and add them to a three-dimensional motion mixer. Mix at a speed of 30-50rpm for 30-60min to obtain a uniformly mixed wear-resistant aggregate. S6. Load the wear-resistant aggregate into the mold and cold press it under a pressure of 15~25MPa using a hydraulic press. The holding time is 30~60s to obtain the green blank of the wear-resistant component. S7. Place the wear-resistant component green blank in a sintering furnace and sinter it under an argon protective atmosphere. The heating rate is 8~12℃ / min, the sintering temperature is 800~900℃, and the holding time is 60~120min. After cooling to room temperature in the furnace, the green blank is taken out to obtain the finished wear-resistant component.

[0045] The technical solution of the present invention will be further described below with reference to specific embodiments.

[0046] Example 1 A method for preparing wear-resistant components from cemented carbide wear resistance test waste includes the following steps: S1. Place the cemented carbide wear resistance test waste in a drying oven to remove moisture. After drying, pass the waste through a 10-mesh standard sieve to obtain first-grade material. S2. Perform magnetic separation on the primary material with a magnetic field strength of 1.0T to obtain the magnetically separated material; S3. Place the magnetically separated material in a tube furnace and demagnetize it by holding it at 350℃ for 45 minutes. After demagnetization, let it cool naturally to room temperature to obtain the material to be graded. S4. The material to be classified is added to the feeding device of the air classifier for separation. The airflow velocity is set to 1.5 m / s, the classifying wheel speed to 2800 rpm, the feed rate to 20 kg / h, and the negative pressure in the classifying chamber to -650 Pa. WC-Co abrasive is obtained. The WC-Co abrasive is characterized, and its SEM image is shown below. Figure 1 As shown, Figure 1 This indicates that the WC-Co abrasive particles have sharp edges and distinct corners, with a rough surface covered with micro-protrusions and sharp corners, retaining the natural grinding corner morphology of WC-Co particles; S5. Weigh 80% of WC-Co abrasive and 20% of metal matrix powder with a particle size of 100μm by mass percentage and add them to a three-dimensional motion mixer. Mix at 40rpm for 45min to obtain a uniformly mixed wear-resistant aggregate. The metal matrix powder is a copper-nickel mixed powder obtained by mixing copper powder and nickel powder in a mass ratio of 3:1. S6. Load the wear-resistant aggregate into the mold and cold press it under 20MPa pressure using a hydraulic press. The holding time is 45s to obtain the green blank of the wear-resistant component. S7. Place the wear-resistant component green blank in a sintering furnace and sinter it under an argon protective atmosphere. The heating rate is 10℃ / min, the sintering temperature is 850℃, and the holding time is 90min. After cooling to room temperature in the furnace, the green blank is taken out to obtain the finished wear-resistant component.

[0047] The performance of the finished wear-resistant component prepared in this embodiment was tested. The test results showed that the hardness HV30 of the wear-resistant component was 1380 and the impact toughness was 16.0 J / cm. 2 The density is 92.1%.

[0048] Example 2 A method for preparing wear-resistant components from cemented carbide wear resistance test waste includes the following steps: S1. Place the cemented carbide wear resistance test waste in a drying oven to remove moisture. After drying, pass the waste through a 10-mesh standard sieve to obtain first-grade material. S2. Perform magnetic separation on the primary material with a magnetic field strength of 0.8T to obtain the magnetically separated material; S3. Place the magnetically separated material in a tube furnace and keep it at 300℃ for 60 minutes for demagnetization. After demagnetization, let it cool naturally to room temperature to obtain the material to be graded. S4. Add the material to be classified into the feeding device of the air classifier for separation. Set the airflow velocity to 1.2m / s, the classifier wheel speed to 2000rpm, the feed rate to 10kg / h, and the negative pressure of the classifier chamber to -500Pa to obtain WC-Co grinding material. S5. Weigh 70% of WC-Co abrasive and 30% of nickel powder with a particle size of 100μm by mass percentage and add them to a three-dimensional motion mixer. Mix at 30rpm for 60min to obtain a uniformly mixed wear-resistant aggregate. S6. Load the wear-resistant aggregate into the mold and cold press it under 15MPa pressure using a hydraulic press. The holding time is 60s to obtain the green blank of the wear-resistant component. S7. Place the wear-resistant component green blank in a sintering furnace and sinter it under an argon protective atmosphere. The heating rate is 10℃ / min, the sintering temperature is 800℃, and the holding time is 120min. After cooling to room temperature in the furnace, the green blank is taken out to obtain the finished wear-resistant component.

[0049] The performance of the finished wear-resistant component prepared in this embodiment was tested. The test results showed that the hardness HV30 of the wear-resistant component was 1250 and the impact toughness was 14.5 J / cm. 2 The density is 89.5%.

[0050] Example 3 A method for preparing wear-resistant components from cemented carbide wear resistance test waste includes the following steps: S1. Place the cemented carbide wear resistance test waste in a drying oven to remove moisture. After drying, pass the waste through a 10-mesh standard sieve to obtain first-grade material. S2. Perform magnetic separation on the primary material with a magnetic field strength of 1.2T to obtain the magnetically separated material. S3. Place the magnetically separated material in a tube furnace and keep it at 400℃ for 30 minutes for demagnetization. After demagnetization, let it cool naturally to room temperature to obtain the material to be classified. S4. Add the material to be classified into the feeding device of the air classifier for separation. Set the airflow velocity to 1.8m / s, the classifier wheel speed to 3500rpm, the feed rate to 30kg / h, and the negative pressure of the classifier chamber to -800Pa to obtain WC-Co abrasive. S5. Weigh 90% of WC-Co abrasive and 10% of copper powder with a particle size of 100μm by mass percentage and add them to a three-dimensional motion mixer. Mix at 50rpm for 30min to obtain a uniformly mixed wear-resistant aggregate. S6. Load the wear-resistant aggregate into the mold and cold press it under 25MPa pressure using a hydraulic press. The holding time is 30s to obtain the green blank of the wear-resistant component. S7. Place the green blank of the wear-resistant component in a sintering furnace and sinter it under an argon protective atmosphere. The heating rate is 10℃ / min, the sintering temperature is 900℃, and the holding time is 60min. After cooling to room temperature in the furnace, the green blank is taken out to obtain the finished wear-resistant component.

[0051] The performance of the finished wear-resistant component prepared in this embodiment was tested. The test results showed that the hardness HV30 of the wear-resistant component was 1460 and the impact toughness was 10.8 J / cm. 2 The density is 90.8%.

[0052] Example 4 A method for preparing wear-resistant components from cemented carbide wear resistance test waste includes the following steps: S1. Place the cemented carbide wear resistance test waste in a drying oven to remove moisture. After drying, pass the waste through a 10-mesh standard sieve to obtain first-grade material. S2. Perform magnetic separation on the primary material with a magnetic field strength of 0.9T to obtain the magnetically separated material; S3. Place the magnetically separated material in a tube furnace and keep it at 320℃ for 50 minutes for demagnetization. After demagnetization, let it cool naturally to room temperature to obtain the material to be classified. S4. Add the material to be classified into the feeding device of the air classifier for separation. Set the airflow velocity to 1.4 m / s, the classifier wheel speed to 2500 rpm, the feed rate to 15 kg / h, and the negative pressure of the classifier chamber to -600 Pa to obtain WC-Co grinding material. S5. Weigh 75% of WC-Co abrasive and 25% of copper powder with a particle size of 100μm by mass percentage and add them to a three-dimensional motion mixer. Mix at 35rpm for 50min to obtain a uniformly mixed wear-resistant aggregate. S6. Load the wear-resistant aggregate into the mold and cold press it under 18MPa pressure using a hydraulic press. The holding time is 50s to obtain the green blank of the wear-resistant component. S7. Place the green blank of the wear-resistant component in a sintering furnace and sinter it under an argon protective atmosphere. The heating rate is 10℃ / min, the sintering temperature is 820℃, and the holding time is 100min. After cooling to room temperature in the furnace, the green blank is taken out to obtain the finished wear-resistant component.

[0053] The performance of the finished wear-resistant component prepared in this embodiment was tested. The test results showed that the hardness HV30 of the wear-resistant component was 1320 and the impact toughness was 12.6 J / cm. 2 The density is 90.1%.

[0054] Example 5 A method for preparing wear-resistant components from cemented carbide wear resistance test waste includes the following steps: S1. Place the cemented carbide wear resistance test waste in a drying oven to remove moisture. After drying, pass the waste through a 10-mesh standard sieve to obtain first-grade material. S2. Perform magnetic separation on the primary material with a magnetic field strength of 0.95T to obtain the magnetically separated material. S3. Place the magnetically separated material in a tube furnace and demagnetize it by holding it at 380℃ for 35 minutes. After demagnetization, let it cool naturally to room temperature to obtain the material to be graded. S4. Add the material to be classified into the feeding device of the air classifier for separation. Set the airflow velocity to 1.6m / s, the classifier wheel speed to 3000rpm, the feed rate to 25kg / h, and the negative pressure of the classifier chamber to -700Pa to obtain WC-Co grinding material. S5. Weigh 85% of WC-Co abrasive and 15% of nickel powder with a particle size of 100μm by mass percentage and add them to a three-dimensional motion mixer. Mix at 45rpm for 40min to obtain a uniformly mixed wear-resistant aggregate. S6. Load the wear-resistant aggregate into the mold and cold press it under 22MPa pressure using a hydraulic press. The holding time is 35s to obtain the green blank of the wear-resistant component. S7. Place the wear-resistant component green blank in a sintering furnace and sinter it under an argon protective atmosphere. The heating rate is 10℃ / min, the sintering temperature is 880℃, and the holding time is 70min. After cooling to room temperature in the furnace, the green blank is taken out to obtain the finished wear-resistant component.

[0055] The performance of the finished wear-resistant component prepared in this embodiment was tested. The test results showed that the hardness HV30 of the wear-resistant component was 1420 and the impact toughness was 11.5 J / cm. 2 The density is 91.5%.

[0056] Example 6 A method for preparing wear-resistant components from cemented carbide wear resistance test waste includes the following steps: S1. Place the cemented carbide wear resistance test waste in a drying oven to remove moisture. After drying, pass the waste through a 10-mesh standard sieve to obtain first-grade material. S2. Perform magnetic separation on the primary material with a magnetic field strength of 1.10T to obtain the magnetically separated material. S3. Place the magnetically separated material in a tube furnace and keep it at 360°C for 40 minutes for demagnetization. After demagnetization, let it cool naturally to room temperature to obtain the material to be graded. S4. Add the material to be classified into the feeding device of the air classifier for separation. Set the air velocity to 1.3m / s, the classifier wheel speed to 2200rpm, the feed rate to 18kg / h, and the negative pressure of the classifier chamber to -550Pa to obtain WC-Co grinding material. S5. Weigh 82% of WC-Co abrasive and 18% of metal matrix powder with a particle size of 100μm by mass percentage and add them to a three-dimensional motion mixer. Mix at 38rpm for 55min to obtain a uniformly mixed wear-resistant aggregate. The metal matrix powder is a copper-nickel mixed powder obtained by mixing copper powder and nickel powder in a mass ratio of 5:4. S6. Load the wear-resistant aggregate into the mold and cold press it under 20MPa pressure using a hydraulic press. The holding time is 40s to obtain the green blank of the wear-resistant component. S7. Place the wear-resistant component green blank in a sintering furnace and sinter it under an argon protective atmosphere. The heating rate is 10℃ / min, the sintering temperature is 840℃, and the holding time is 85min. After cooling to room temperature in the furnace, the green blank is taken out to obtain the finished wear-resistant component.

[0057] The performance of the finished wear-resistant component prepared in this embodiment was tested. The test results showed that the hardness HV30 of the wear-resistant component was 1360 and the impact toughness was 12.8 J / cm. 2 The density is 90.7%.

[0058] Comparative Example 1 A method for preparing wear-resistant components from cemented carbide wear resistance test waste includes the following steps: S1. Place the cemented carbide wear resistance test waste in a drying oven to remove moisture. After drying, pass the waste through a 10-mesh standard sieve to obtain first-grade material. S2. Add the primary material to the feeding device of the air classifier for separation. Set the airflow velocity to 1.5 m / s, the classifier wheel speed to 2800 rpm, the feed rate to 20 kg / h, and the negative pressure of the classifier chamber to -650 Pa to obtain WC-Co abrasive. S3. Weigh 80% of WC-Co abrasive and 20% of metal matrix powder with a particle size of 100μm by mass percentage and add them to a three-dimensional motion mixer. Mix at 40rpm for 45min to obtain a uniformly mixed wear-resistant aggregate. The metal matrix powder is a copper-nickel mixed powder obtained by mixing copper powder and nickel powder in a mass ratio of 3:1. S4. Load the wear-resistant aggregate into the mold and cold press it under 20MPa pressure using a hydraulic press. The holding time is 45s to obtain the green blank of the wear-resistant component. S5. Place the wear-resistant component green blank in a sintering furnace and sinter it under an argon protective atmosphere. The heating rate is 10℃ / min, the sintering temperature is 850℃, and the holding time is 90min. After cooling to room temperature in the furnace, the green blank is taken out to obtain the finished wear-resistant component.

[0059] The performance of the finished wear-resistant component prepared in this comparative example was tested. The test results showed that the hardness HV30 of the wear-resistant component was 1020 and the impact toughness was 9.5 J / cm. 2 The density is 82.3%.

[0060] Compared to Example 1, this comparative example omits the magnetic separation and demagnetization steps, directly performing airflow classification. The waste contains a large amount of 20# steel shavings, whose density is much lower than WC-Co, but these were not pre-removed by magnetic separation. The steel shavings retain residual magnetism, which can magnetically attract and bind with the inductively magnetized WC-Co particles after crushing, hindering effective separation and interfering with classification. The final product has a density of only 82.3%, a hardness HV30 of only 1020, and an impact toughness of only 9.5 J / cm². 2 The product performance was significantly lower than that of Example 1, proving that a single airflow stage could not handle the cemented carbide wear resistance test waste.

[0061] Comparative Example 2 A method for preparing wear-resistant components from cemented carbide wear resistance test waste includes the following steps: S1. Place the cemented carbide wear resistance test waste in a drying oven to remove moisture. After drying, pass the waste through a 10-mesh standard sieve to obtain first-grade material. S2. Perform magnetic separation on the primary material with a magnetic field strength of 1.0T to obtain the magnetically separated material; S3. The magnetically separated material is added to the feeding device of the air classifier for separation. The airflow velocity is set to 1.5m / s, the classifier wheel speed is set to 2800rpm, the feed rate is set to 20kg / h, and the negative pressure of the classifier chamber is set to -650Pa to obtain WC-Co grinding material. S4. Weigh 80% of WC-Co abrasive and 20% of metal matrix powder with a particle size of 100μm by mass percentage and add them to a three-dimensional motion mixer. Mix at 40rpm for 45min to obtain a uniformly mixed wear-resistant aggregate. The metal matrix powder is a copper-nickel mixed powder obtained by mixing copper powder and nickel powder in a mass ratio of 3:1. S5. Load the wear-resistant aggregate into the mold and cold press it under 20MPa pressure using a hydraulic press. The holding time is 45s to obtain the green blank of the wear-resistant component. S6. Place the wear-resistant component green blank in a sintering furnace and sinter it under an argon protective atmosphere. The heating rate is 10℃ / min, the sintering temperature is 850℃, and the holding time is 90min. After cooling to room temperature in the furnace, the green blank is taken out to obtain the finished wear-resistant component.

[0062] The performance of the wear-resistant component prepared in this comparative example was tested. The test results showed that the hardness HV30 of the wear-resistant component was 1084 and the impact toughness was 8.8 J / cm. 2 The density is 83.1%.

[0063] Compared to Example 1, this comparative example involved magnetic separation but no demagnetization. The magnetic separation process removed most of the steel chips while magnetizing the remaining fine steel chips (<100μm), generating remanence and coercivity. These magnetized steel chips formed magnetic agglomerates during air classification. Due to the weak magnetism of the cobalt phase in WC-Co, these agglomerates of magnetized steel chips carried WC-Co particles into sedimentation, leading to the failure of WC-Co to separate from the steel chips. The final product had a density of 83.1%, a hardness (HV30) of only 1084, and an impact toughness of only 8.8 J / cm², significantly lower than Example 1, demonstrating that the demagnetization step plays a crucial role in ensuring the accuracy of air classification.

[0064] Comparative Example 3 A method for preparing wear-resistant components from cemented carbide wear resistance test waste includes the following steps: S1. Place the cemented carbide wear resistance test waste in a drying oven to remove moisture. After drying, pass the waste through a 10-mesh standard sieve to obtain first-grade material. S2. The primary material is added to the feeding device of the air classifier for separation. The airflow velocity is set to 1.5m / s, the classifier wheel speed is 4000rpm, the feed rate is 20kg / h, and the negative pressure of the classifier chamber is -650Pa. A small amount of WC-Co abrasive material is separated, and the recovery fails.

[0065] Compared with Example 1, this comparative example only performed airflow classification. Due to the excessively high rotation speed of the classifier wheel, the WC-Co particles were broken by excessive centrifugal collision, resulting in morphological damage and extremely low recovery rate, leading to recovery failure.

[0066] Comparative Example 4 A method for preparing wear-resistant components from cemented carbide wear resistance test waste includes the following steps: S1. Place the cemented carbide wear resistance test waste in a drying oven to remove moisture. After drying, pass the waste through a 10-mesh standard sieve to obtain first-grade material. S2. The primary material is added to the feeding device of the air classifier for separation. The airflow velocity is set to 1.5 m / s, the classifier wheel speed is 1500 rpm, the feed rate is 20 kg / h, and the negative pressure of the classifier chamber is -650 Pa. A mixture of WC-Co grinding material and steel scrap is obtained, but the recovery fails.

[0067] Compared with Example 1, this comparative example only performed airflow classification, and due to the low rotation speed of the classification wheel and insufficient separation power, the steel chips and WC-Co settled together, resulting in recycling failure.

[0068] Comparative Example 5 A method for preparing wear-resistant components from cemented carbide wear resistance test waste includes the following steps: S1. Place the cemented carbide wear resistance test waste in a drying oven to remove moisture. After drying, pass the waste through a 10-mesh standard sieve to obtain first-grade material. S2. Perform magnetic separation on the primary material with a magnetic field strength of 1.0T to obtain the magnetically separated material; S3. Place the magnetically separated material in a tube furnace and demagnetize it by holding it at 350℃ for 45 minutes. After demagnetization, let it cool naturally to room temperature to obtain the material to be graded. S4. Add the material to be classified into the feeding device of the air classifier for separation. Set the airflow velocity to 1.5m / s, the classifier wheel speed to 2800rpm, the feed rate to 20kg / h, and the negative pressure of the classifier chamber to -650Pa to obtain WC-Co abrasive. S5. Weigh 80% of WC-Co abrasive and 20% of metal matrix powder with a particle size of 100μm by mass percentage and add them to a three-dimensional motion mixer. Mix at 40rpm for 45min to obtain a uniformly mixed wear-resistant aggregate. The metal matrix powder is a copper-nickel mixed powder obtained by mixing copper powder and nickel powder in a mass ratio of 3:1. S6. Load the wear-resistant aggregate into the mold and cold press it under 20MPa pressure using a hydraulic press. The holding time is 45s to obtain the green blank of the wear-resistant component. S7. Place the green blank of the wear-resistant component in a sintering furnace and sinter it under an argon protective atmosphere. The heating rate is 10℃ / min, the sintering temperature is 700℃, and the holding time is 90min. After cooling to room temperature in the furnace, the green blank is taken out to obtain the finished wear-resistant component.

[0069] The performance of the finished wear-resistant component prepared in this comparative example was tested. The test results showed that the wear-resistant component had a hardness (HV30) of 910 and an impact toughness of 8.2 J / cm. 2 The density is 78.5%.

[0070] Comparative Example 6 A method for preparing wear-resistant components from cemented carbide wear resistance test waste includes the following steps: S1. Place the cemented carbide wear resistance test waste in a drying oven to remove moisture. After drying, pass the waste through a 10-mesh standard sieve to obtain first-grade material. S2. Perform magnetic separation on the primary material with a magnetic field strength of 1.0T to obtain the magnetically separated material; S3. Place the magnetically separated material in a tube furnace and demagnetize it by holding it at 350℃ for 45 minutes. After demagnetization, let it cool naturally to room temperature to obtain the material to be graded. S4. Add the material to be classified into the feeding device of the air classifier for separation. Set the airflow velocity to 1.5m / s, the classifier wheel speed to 2800rpm, the feed rate to 20kg / h, and the negative pressure of the classifier chamber to -650Pa to obtain WC-Co abrasive. S5. Weigh 80% of WC-Co abrasive and 20% of metal matrix powder with a particle size of 100μm by mass percentage and add them to a three-dimensional motion mixer. Mix at 40rpm for 45min to obtain a uniformly mixed wear-resistant aggregate. The metal matrix powder is a copper-nickel mixed powder obtained by mixing copper powder and nickel powder in a mass ratio of 3:1. S6. Load the wear-resistant aggregate into the mold and cold press it under 20MPa pressure using a hydraulic press. The holding time is 45s to obtain the green blank of the wear-resistant component. S7. Place the wear-resistant component green blank in a sintering furnace and sinter it under an argon protective atmosphere. The heating rate is 10℃ / min, the sintering temperature is 950℃, and the holding time is 90min. After cooling to room temperature in the furnace, the green blank is taken out to obtain the finished wear-resistant component.

[0071] The performance of the finished wear-resistant component prepared in this comparative example was tested. The test results showed that the hardness HV30 of the wear-resistant component was 1180 and the impact toughness was 7.6 J / cm. 2 The density is 89.2%.

[0072] Comparative Example 7 A method for preparing wear-resistant components from cemented carbide wear resistance test waste includes the following steps: S1. Place the cemented carbide wear resistance test waste in a drying oven to remove moisture. After drying, pass the waste through a 10-mesh standard sieve to obtain first-grade material. S2. Perform magnetic separation on the primary material with a magnetic field strength of 1.0T to obtain the magnetically separated material; S3. Place the magnetically separated material in a tube furnace and demagnetize it by holding it at 350℃ for 45 minutes. After demagnetization, let it cool naturally to room temperature to obtain the material to be graded. S4. Add the material to be classified into the feeding device of the air classifier for separation. Set the airflow velocity to 1.2m / s, the classifier wheel speed to 2000rpm, the feed rate to 10kg / h, and the negative pressure of the classifier chamber to -500Pa to obtain WC-Co grinding material. S5. Weigh 60% of WC-Co abrasive and 40% of nickel powder with a particle size of 100μm by mass percentage and add them to a three-dimensional motion mixer. Mix at 30rpm for 60min to obtain a uniformly mixed wear-resistant aggregate. S6. Load the wear-resistant aggregate into the mold and cold press it under 30MPa pressure using a hydraulic press. The holding time is 60s to obtain the green blank of the wear-resistant component. S7. Place the wear-resistant component green blank in a sintering furnace and sinter it under an argon protective atmosphere. The heating rate is 10℃ / min, the sintering temperature is 800℃, and the holding time is 120min. After cooling to room temperature in the furnace, the green blank is taken out to obtain the finished wear-resistant component.

[0073] The performance of the finished wear-resistant component prepared in this comparative example was tested. The test results showed that the hardness HV30 of the wear-resistant component was 840, and the impact toughness was 16.7 J / cm. 2 The density is 90.5%.

[0074] Comparative Example 8 A method for preparing wear-resistant components from cemented carbide wear resistance test waste includes the following steps: S1. Place the cemented carbide wear resistance test waste in a drying oven to remove moisture. After drying, pass the waste through a 10-mesh standard sieve to obtain first-grade material. S2. Perform magnetic separation on the primary material with a magnetic field strength of 1.0T to obtain the magnetically separated material; S3. Place the magnetically separated material in a tube furnace and demagnetize it by holding it at 350℃ for 45 minutes. After demagnetization, let it cool naturally to room temperature to obtain the material to be graded. S4. Add the material to be classified into the feeding device of the air classifier for separation. Set the airflow velocity to 1.2m / s, the classifier wheel speed to 2000rpm, the feed rate to 10kg / h, and the negative pressure of the classifier chamber to -500Pa to obtain WC-Co grinding material. S5. Weigh 95% of WC-Co abrasive and 5% of nickel powder with a particle size of 100μm by mass percentage and add them to a three-dimensional motion mixer. Mix at 30rpm for 60min to obtain a uniformly mixed wear-resistant aggregate. S6. Load the wear-resistant aggregate into the mold and cold press it under 15MPa pressure using a hydraulic press. The holding time is 60s to obtain the green blank of the wear-resistant component. S7. Place the wear-resistant component green blank in a sintering furnace and sinter it under an argon protective atmosphere. The heating rate is 10℃ / min, the sintering temperature is 800℃, and the holding time is 120min. After cooling to room temperature in the furnace, the green blank is taken out to obtain the finished wear-resistant component.

[0075] The performance of the finished wear-resistant component prepared in this comparative example was tested. The test results showed that the hardness HV30 of the wear-resistant component was 1420, and the impact toughness was 6.3 / cm. 2 The density is 82.7%.

[0076] Comparative Example 9 A method for preparing wear-resistant components from cemented carbide wear resistance test waste differs from Example 1 in that, before step S4, the material to be classified is placed in a planetary ball mill and ball-milled at 450 rpm for 60 min to break down the angular morphology of the WC-Co particles. The remaining steps are the same as in Example 1.

[0077] The performance of the finished wear-resistant component prepared in this comparative example was tested. The test results showed that the wear-resistant component had a hardness (HV30) of 980 and an impact toughness of 5.53 J / cm. 2 The density is 78.2%, and the surface of the wear-resistant component shows fine cracks.

[0078] In summary, this invention provides a method for preparing wear-resistant components from cemented carbide wear resistance test waste. The method provided by this invention, through a process flow that does not include crushing and ball milling, completely preserves the natural grinding angular morphology of WC-Co particles in the waste. Furthermore, it employs an integrated process coupling magnetic separation, demagnetization, and airflow classification to achieve efficient separation of WC-Co cemented carbide particles from alumina abrasives and steel chips. The resulting angular WC-Co abrasive material is mixed with a metal matrix powder, and then cold-pressed and sintered at low temperature to obtain high-performance wear-resistant components. This method of the present invention is concise, energy-efficient, and free of chemical pollution. Without the need for binder accelerators, it significantly improves the interfacial bonding strength and mechanical properties of wear-resistant components, enabling the high-value direct reuse of cemented carbide waste, and has outstanding prospects for industrial application and environmental benefits.

[0079] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A method for preparing wear-resistant components from cemented carbide wear resistance test waste, characterized in that, Includes the following steps: S1. After drying the waste material from the cemented carbide wear resistance test, it is sieved to obtain the first-grade material. S2. Perform magnetic separation on the primary material to obtain the magnetically separated material; S3. The magnetically separated material is demagnetized at 300~400℃ to obtain the material to be classified. S4. The material to be classified is subjected to airflow classification treatment. The airflow velocity of the airflow classification treatment is 1.2~1.8m / s, the classification wheel speed is 2000~3500rpm, and the negative pressure of the classification chamber is -800~-500Pa to obtain WC-Co abrasive material. S5. Mix the WC-Co abrasive with the metal matrix powder to obtain wear-resistant aggregate; S6. The wear-resistant aggregate is cold-pressed into a green blank of a wear-resistant component; S7. The wear-resistant component green blank is sintered under an inert protective atmosphere to obtain the finished wear-resistant component.

2. The method for preparing wear-resistant components according to claim 1, characterized in that, In step S1, the cemented carbide wear resistance test waste contains WC-Co cemented carbide particles, alumina abrasive particles, and steel chips; the WC-Co cemented carbide particles have a grinding angular morphology naturally formed during the wear resistance test process.

3. The method for preparing wear-resistant components according to claim 1, characterized in that, In step S2, the magnetic field strength of the magnetic separation process is 0.8~1.2T.

4. The method for preparing wear-resistant components according to claim 1, characterized in that, In step S3, the demagnetization time for the demagnetization process is 30-60 minutes.

5. The method for preparing wear-resistant components according to claim 1, characterized in that, In step S4, the feed rate of the airflow classification is 10~30 kg / h.

6. The method for preparing wear-resistant components according to claim 1, characterized in that, In step S5, 70-90% of WC-Co abrasive and 10-30% of metal matrix powder are weighed by mass percentage and mixed at a speed of 30-50 rpm for 30-60 min.

7. The method for preparing wear-resistant components according to claim 1 or 6, characterized in that, The metal matrix powder is copper powder, nickel powder, or a mixture of copper and nickel powder, with a particle size of 50~150μm.

8. The method for preparing wear-resistant components according to claim 1, characterized in that, In step S6, the pressure of cold pressing is 15~25MPa, and the holding time is 30~60s.

9. The method for preparing wear-resistant components according to claim 1, characterized in that, In step S7, the sintering heating rate is 8~12℃ / min, the sintering temperature is 800~900℃, and the holding time is 60~120min.

10. The method for preparing wear-resistant components according to claim 1, characterized in that, In step S7, the finished wear-resistant component has a hardness HV30 ≥ 1250 and an impact toughness ≥ 10.8 J / cm. 2 Density ≥89.5%.

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