Modified tungsten-nickel-iron powder, preparation method and application thereof

Abstract

The application provides a modified tungsten-nickel-iron powder, a preparation method and application thereof. The method is: under the action of a binder, a lubricant and an additive, a high-speed fusion modification method is used to treat the tungsten-nickel-iron powder to obtain the modified tungsten-nickel-iron powder; the temperature of the high-speed fusion modification is 6-12 DEG C, the frequency is 10-40 Hz, and the time is 15-120 min. Through the high-speed fusion modification, the binding force and dispersibility between powder particles are enhanced, and the powder density and flowability are improved; the modified tungsten-nickel-iron powder has high regularity, approaches to a spherical shape, has a smooth surface, is uniform in size, and has a narrow particle size distribution. When the modified tungsten-nickel-iron powder is used to prepare a tensile part, the tensile strength of the tensile part reaches 982 MPa, the elongation after fracture reaches 27.5%, the impact absorption energy reaches 6.08 J, and the impact toughness value reaches 7.61 J / cm 2 , and the strength and toughness are significantly improved, and the performance requirements of materials in high-end fields can be met.

Description

Technical Field

[0001] This invention belongs to the field of modified high-density alloy powder technology, specifically relating to a modified tungsten-nickel-iron powder, its preparation method, and its application. Background Technology

[0002] In many fields of modern industry, such as aerospace, automobile manufacturing, and machinery equipment, extremely stringent requirements are placed on the performance of metallic materials. Tungsten alloys, as a widely used raw material for forging basic components, directly affect the reliability and service life of the entire equipment or product. Tungsten-nickel-iron alloys, with their unique performance advantages, have shown great potential in manufacturing high-strength, high-temperature resistant parts, becoming one of the hottest materials for research and application.

[0003] Tungsten-nickel-iron alloys use tungsten as the base material, typically with a tungsten content between 85wt% and 98wt%. Tungsten is prized for its extremely high melting point (3422℃) and high density (19.3g / cm³). 3 The excellent high-temperature strength provides the alloy with a robust skeletal structure, endowing it with superior resistance to deformation and high-temperature stability. For example, in high-temperature components of aero-engines, tungsten-nickel-iron alloys can withstand extremely high temperatures and mechanical stresses, ensuring stable engine operation. Nickel and iron, as the binder phases in the alloy, form a face-centered cubic γ-phase, uniformly surrounding the tungsten particles. The nickel-iron ratio typically fluctuates between (6:4) and (10:5), and this ratio significantly affects the alloy's performance. An appropriate amount of nickel can effectively suppress the abnormal growth of tungsten particles during sintering, refine the grains, and enhance the alloy's toughness and machinability; iron works synergistically with nickel, improving the overall strength of the alloy through a solid solution strengthening mechanism, and to some extent reducing raw material costs, thus balancing the alloy's cost-effectiveness.

[0004] However, in practical applications, traditional tungsten-nickel-iron powder and its preparation process have many limitations, severely restricting the improvement of tungsten alloy strength. From the perspective of powder characteristics, conventional tungsten-nickel-iron powder has irregular particle morphology and a wide particle size distribution (typically D50 of 3-5 μm). This leads to uneven powder accumulation during molding, resulting in high internal porosity and significantly weakening the density and strength of the stretched parts. For example, when preparing parts using powder metallurgy, these pores become stress concentration points, easily inducing crack propagation under stress and reducing the load-bearing capacity of the parts.

[0005] Existing powder modification and forming processes are also insufficient to meet the requirements for preparing high-strength parts. While common mechanical ball milling modification can refine powder particles to some extent, prolonged milling introduces a large number of impurities, causing powder lattice distortion, impairing the powder's sintering activity, and resulting in increased internal structural defects in the sintered drawn parts, with limited strength improvement. Chemical modification methods, such as surface coating, can improve the surface properties of powder, but suffer from uneven coating layers, easy detachment, and the large amount of chemical reagents used in the modification process pollutes the environment, contradicting the concept of green manufacturing. Regarding forming processes, traditional compression molding struggles to uniformly fill the complex mold cavity with powder, leading to significant differences in density and properties in different parts of the drawn part. Conventional sintering processes, such as ordinary vacuum sintering, struggle to effectively control grain growth while increasing density, easily resulting in a trade-off between strength and toughness in the drawn parts.

[0006] Relevant research data shows that tungsten-nickel-iron (TNI) tensile parts prepared using traditional processes often only achieve a tensile strength of 700-930 MPa and an elongation of around 15%-20%, far from meeting the high-performance requirements of some high-end fields. For example, in the aerospace field, some key components require tensile strengths exceeding 950 MPa and elongations of no less than 25% to ensure safe and reliable operation under extreme conditions. Therefore, developing a novel modification technology that can significantly improve the quality of TNI powder and thus enhance the strength of parts has become a key challenge that urgently needs to be overcome in the field of materials science. This has significant practical implications for promoting the development of modern industry towards higher performance and lighter weight. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a modified tungsten nickel iron powder, its preparation method and application, which addresses the shortcomings of the prior art and solves the problem of insufficient strength of tensile parts prepared by tungsten nickel iron powder in the prior art.

[0008] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a method for preparing modified tungsten-nickel-iron powder, the method being as follows: With the help of binders, lubricants and additives, tungsten nickel iron powder is treated by a high-speed fusion modification method to obtain modified tungsten nickel iron powder. The temperature during the high-speed fusion modification is 6~12℃; the frequency during the high-speed fusion modification is 10~40 Hz; and the high-speed fusion modification time is 15~120 min.

[0009] Preferably, the particle size of the tungsten-nickel-iron powder is 3~5 µm.

[0010] Preferably, the mass ratio of tungsten, nickel and iron in the tungsten-nickel-iron powder is (90~98):(1~6):(1~4).

[0011] Preferably, the binder is polyvinyl alcohol and / or polyethylene glycol, and the amount used is 1 to 5 wt% of the tungsten-nickel-iron powder.

[0012] Preferably, the lubricant is stearic acid or / and stearate, and the amount used is 0.5 to 3 wt% of the tungsten nickel iron powder.

[0013] Preferably, the additive consists of a reinforcing agent and an antioxidant, and is used in an amount of 0.5 to 2 wt% of the tungsten-nickel-iron powder.

[0014] Preferably, the reinforcing agent is cerium oxide, and the amount used is 0.3~1.5 wt% of the tungsten nickel iron powder; the antioxidant is yttrium oxide, and the amount used is 0.2~0.8 wt% of the tungsten nickel iron powder.

[0015] Preferably, the high-speed fusion modification method uses a high-speed fusion machine for modification.

[0016] The present invention also provides a modified tungsten-nickel-iron powder prepared by the above method.

[0017] The present invention also provides the application of the modified tungsten nickel iron powder in the preparation of tensile parts, wherein the tensile strength of the tensile parts reaches 950 MPa or more.

[0018] This invention has significant technical advantages compared to existing technologies: 1. Compared with the prior art, the present invention uses a high-speed fusion machine to fuse and modify tungsten nickel iron powder, which enhances the bonding force and dispersibility between powder particles, improves the density and flowability of the powder. The modified tungsten nickel iron powder particles prepared by the present invention have high regularity, are close to spherical, with a sphericity of 93%, and have smooth surfaces, uniform size, and narrow particle size distribution.

[0019] 2. The modified tungsten-nickel-iron powder prepared by this invention can be used to prepare tensile parts. The tensile parts obtained have a tensile strength of 982 MPa, an elongation after fracture of 27.5%, an impact absorption energy of 6.08 J, and an impact toughness of 7.61 J / cm. 2 This significantly improves its strength and toughness, enabling it to meet the performance requirements of high-end materials.

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. Attached Figure Description

[0021] Figure 1 The image shows the SEM image of the unmodified tungsten-nickel-iron mixed powder in Comparative Example 1, where b is a magnified view of a. Figure 2 The particle size distribution diagram is shown for the unmodified tungsten-nickel-iron mixed powder in Comparative Example 1. Figure 3 The image shown is a SEM image of the modified tungsten nickel-iron powder obtained in Example 1 of the present invention, where b is a magnified view of a. Figure 4 This is a particle size distribution diagram of the modified tungsten-nickel-iron powder obtained in Example 1 of the present invention; Figure 5 Here is a SEM image of the modified tungsten-nickel-iron powder obtained in Example 2 of the present invention, where b is a partial magnified view of a; Figure 6 This is a particle size distribution diagram of the modified tungsten-nickel-iron powder obtained in Example 2 of the present invention; Figure 7 Here is a SEM image of the modified tungsten nickel-iron powder obtained in Example 3 of the present invention, where b is a partial magnified view of a; Figure 8 This is a particle size distribution diagram of the modified tungsten-nickel-iron powder obtained in Example 3 of the present invention; Figure 9 Here is a SEM image of the modified tungsten nickel-iron powder obtained in Example 4 of the present invention, where b is a partial magnified view of a; Figure 10 This is a particle size distribution diagram of the modified tungsten-nickel-iron powder obtained in Example 4 of the present invention; Figure 11 Here is a SEM image of the modified tungsten nickel-iron powder obtained in Example 5 of the present invention, where b is a partial magnified view of a; Figure 12 This is a particle size distribution diagram of the modified tungsten-nickel-iron powder obtained in Example 5 of the present invention; Figure 13 Here is a SEM image of the modified tungsten nickel-iron powder obtained in Example 6 of the present invention, where b is a partial magnified view of a; Figure 14 This is a particle size distribution diagram of the modified tungsten-nickel-iron powder obtained in Example 6 of the present invention; Figure 15 Here is a SEM image of the modified tungsten nickel-iron powder obtained in Example 7 of the present invention, where b is a partial magnified view of a; Figure 16 This is a particle size distribution diagram of the modified tungsten-nickel-iron powder obtained in Example 7 of the present invention; Figure 17 Here is a SEM image of the modified tungsten nickel-iron powder obtained in Example 8 of the present invention, where b is a partial magnified view of a; Figure 18 This is a particle size distribution diagram of the modified tungsten-nickel-iron powder obtained in Example 8 of the present invention; Figure 19SEM images of the cross-section of the tensile component prepared from the unmodified tungsten-nickel-iron mixed powder in Comparative Example 1 are shown. In the images, c is the cross-section of the alloy for tensile strength testing, b is a partial view of c, a is a magnified view of b, f is the cross-section of the alloy for impact toughness testing, e is a partial view of f, and d is a magnified view of e. Figure 20 SEM images of the cross-section of the tensile alloy prepared by the modified tungsten nickel iron powder in Example 1 of the present invention are shown. In the images, c is the cross-section of the alloy for tensile strength test, b is a partial view of c, a is a partial enlarged view of b, f is the cross-section of the alloy for impact toughness test, e is a partial view of f, and d is a partial enlarged view of e. Figure 21 SEM images of the cross-section of the tensile component prepared by the modified tungsten nickel iron powder in Example 2 of the present invention are shown. In the images, c is the cross-section of the alloy for tensile strength test, b is a partial view of c, a is a magnified view of b, f is the cross-section of the alloy for impact toughness test, e is a partial view of f, and d is a magnified view of e. Figure 22 SEM images of the cross-section of the tensile alloy prepared by the modified tungsten nickel iron powder in Example 3 of the present invention are shown. In the images, c is the cross-section of the alloy for tensile strength test, b is a partial view of c, a is a partial enlarged view of b, f is the cross-section of the alloy for impact toughness test, e is a partial view of f, and d is a partial enlarged view of e. Figure 23 SEM images of the cross-section of the tensile component prepared by the modified tungsten nickel iron powder in Example 4 of the present invention are shown. In the images, c is the cross-section of the alloy for tensile strength test, b is a partial view of c, a is a partial enlarged view of b, f is the cross-section of the alloy for impact toughness test, e is a partial view of f, and d is a partial enlarged view of e. Figure 24 SEM images of the cross-section of the tensile component prepared by the modified tungsten nickel iron powder in Example 5 of the present invention are shown. In the images, c is the cross-section of the alloy for tensile strength test, b is a partial view of c, a is a partial enlarged view of b, f is the cross-section of the alloy for impact toughness test, e is a partial view of f, and d is a partial enlarged view of e. Figure 25 SEM images of the cross-section of the tensile component prepared by the modified tungsten nickel iron powder in Example 6 of the present invention are shown. In the images, c is the cross-section of the alloy for tensile strength test, b is a partial view of c, a is a magnified view of b, f is the cross-section of the alloy for impact toughness test, e is a partial view of f, and d is a magnified view of e. Figure 26 SEM images of the cross-section of the tensile component prepared by the modified tungsten nickel iron powder in Example 7 of the present invention are shown. In the images, c is the cross-section of the alloy for tensile strength test, b is a partial view of c, a is a magnified view of b, f is the cross-section of the alloy for impact toughness test, e is a partial view of f, and d is a magnified view of e. Figure 27SEM images of the cross-section of the tensile alloy prepared by the modified tungsten nickel iron powder in Example 8 of the present invention are shown. In the images, c is the cross-section of the alloy for tensile strength test, b is a partial view of c, a is a magnified view of b, f is the cross-section of the alloy for impact toughness test, e is a partial view of f, and d is a magnified view of e. Detailed Implementation

[0022] The high-speed fusion machine used in this invention is the Donggui Precision Machinery TSA-350.

[0023] The tungsten-nickel-iron powder used in Examples 1-8 of this invention is spherical with a particle size of 3-5 µm, wherein the mass ratio of tungsten, nickel, and iron is 93:5:2.

[0024] Example 1 This embodiment describes a method for preparing modified tungsten-nickel-iron powder. The method is as follows: 1000 g of spherical tungsten-nickel-iron powder (tungsten, nickel, and iron in a mass ratio of 93:5:2) was weighed and added to the vessel of a high-speed fusion machine. Then, 30 g of binder (polyethylene glycol), 20 g of lubricant (stearate), 10 g of reinforcing agent (cerium oxide), and 8 g of antioxidant (yttrium oxide) were added to perform high-speed fusion modification treatment on the tungsten-nickel-iron powder. The high-speed fusion machine was used at a frequency of 20 Hz, a processing time of 15 min, and a processing temperature of 6~10℃. After the modification was completed, spherical modified tungsten-nickel-iron powder was obtained.

[0025] Example 2 This embodiment describes a method for preparing modified tungsten-nickel-iron powder. The method is as follows: 1000 g of spherical tungsten-nickel-iron powder (tungsten, nickel, and iron in a mass ratio of 93:5:2) was weighed and added to the vessel of a high-speed fusion machine. Then, 30 g of binder (polyethylene glycol), 20 g of lubricant (stearate), 10 g of reinforcing agent (cerium oxide), and 8 g of antioxidant (yttrium oxide) were added to perform high-speed fusion modification treatment on the tungsten-nickel-iron powder. The high-speed fusion machine was used at a frequency of 20 Hz, a processing time of 30 min, and a processing temperature of 6~10℃. After the modification was completed, spherical modified tungsten-nickel-iron powder was obtained.

[0026] Example 3 This embodiment describes a method for preparing modified tungsten-nickel-iron powder. The method is as follows: 1000 g of spherical tungsten-nickel-iron powder (tungsten, nickel, and iron in a mass ratio of 93:5:2) was weighed and added to the vessel of a high-speed fusion machine. Then, 30 g of binder (polyethylene glycol), 20 g of lubricant (stearate), 10 g of reinforcing agent (cerium oxide), and 8 g of antioxidant (yttrium oxide) were added to perform high-speed fusion modification treatment on the tungsten-nickel-iron powder. The high-speed fusion machine was used at a frequency of 20 Hz, a processing time of 45 min, and a processing temperature of 6~10℃. After the modification was completed, spherical modified tungsten-nickel-iron powder was obtained.

[0027] Example 4 This embodiment describes a method for preparing modified tungsten-nickel-iron powder. The method is as follows: 1000 g of spherical tungsten-nickel-iron powder (tungsten, nickel, and iron in a mass ratio of 93:5:2) was weighed and added to the vessel of a high-speed fusion machine. Then, 30 g of binder (polyethylene glycol), 20 g of lubricant (stearate), 10 g of reinforcing agent (cerium oxide), and 8 g of antioxidant (yttrium oxide) were added to perform high-speed fusion modification treatment on the tungsten-nickel-iron powder. The high-speed fusion machine was used at a frequency of 20 Hz, a processing time of 60 min, and a processing temperature of 6~10℃. After the modification was completed, spherical modified tungsten-nickel-iron powder was obtained.

[0028] Example 5 This embodiment describes a method for preparing modified tungsten-nickel-iron powder. The method is as follows: 1000 g of spherical tungsten-nickel-iron powder (tungsten, nickel, and iron in a mass ratio of 93:5:2) was weighed and added to the vessel of a high-speed fusion machine. Then, 30 g of binder (polyethylene glycol), 20 g of lubricant (stearate), 10 g of reinforcing agent (cerium oxide), and 8 g of antioxidant (yttrium oxide) were added to perform high-speed fusion modification treatment on the tungsten-nickel-iron powder. The high-speed fusion machine was used at a frequency of 20 Hz, a processing time of 75 min, and a processing temperature of 6~10℃. After the modification was completed, spherical modified tungsten-nickel-iron powder was obtained.

[0029] Example 6 This embodiment describes a method for preparing modified tungsten-nickel-iron powder. The method is as follows: 1000 g of spherical tungsten-nickel-iron powder (tungsten, nickel, and iron in a mass ratio of 93:5:2) was weighed and added to the vessel of a high-speed fusion machine. Then, 30 g of binder (polyethylene glycol), 20 g of lubricant (stearate), 10 g of reinforcing agent (cerium oxide), and 8 g of antioxidant (yttrium oxide) were added to perform high-speed fusion modification treatment on the tungsten-nickel-iron powder. The high-speed fusion machine was used at a frequency of 20 Hz, a processing time of 90 min, and a processing temperature of 6~10℃. After the modification was completed, spherical modified tungsten-nickel-iron powder was obtained.

[0030] Example 7 This embodiment describes a method for preparing modified tungsten-nickel-iron powder. The method is as follows: 1000 g of spherical tungsten-nickel-iron powder (tungsten, nickel, and iron in a mass ratio of 93:5:2) was weighed and added to the vessel of a high-speed fusion machine. Then, 30 g of binder (polyethylene glycol), 20 g of lubricant (stearate), 10 g of reinforcing agent (cerium oxide), and 8 g of antioxidant (yttrium oxide) were added to perform high-speed fusion modification treatment on the tungsten-nickel-iron powder. The high-speed fusion machine was used at a processing frequency of 20 Hz, a processing time of 105 min, and a processing temperature of 6~10℃. After the modification was completed, spherical modified tungsten-nickel-iron powder was obtained.

[0031] Example 8 This embodiment describes a method for preparing modified tungsten-nickel-iron powder. The method is as follows: 1000 g of spherical tungsten-nickel-iron powder (tungsten, nickel, and iron in a mass ratio of 93:5:2) was weighed and added to the vessel of a high-speed fusion machine. Then, 30 g of binder (polyethylene glycol), 20 g of lubricant (stearate), 10 g of reinforcing agent (cerium oxide), and 8 g of antioxidant (yttrium oxide) were added to perform high-speed fusion modification treatment on the tungsten-nickel-iron powder. The high-speed fusion machine was used at a frequency of 20 Hz, a processing time of 120 min, and a processing temperature of 6~10℃. After the modification was completed, spherical modified tungsten-nickel-iron powder was obtained.

[0032] The specific operation process is as follows: First, the spherical tungsten-nickel-iron powder to be modified is weighed and added to the vessel of a high-speed fusion machine. Then, the modification parameters are set, and the tungsten-nickel-iron powder is modified under the high-speed action of the high-speed fusion machine. This makes the modified tungsten-nickel-iron powder structure more compact, the surface smoother and rounder, and the sphericity higher. The material added to the vessel forms a three-dimensional flow under the action of the rotor's tilt and high-speed rotation. The impact force, compressive force, and shear force generated by the collision between the rotor, the wall, and the powder are continuously applied to the surface of the tungsten-nickel-iron powder. With the accompanying composite effect, the micro-powder is repeatedly solidified on the surface of the masterbatch, achieving both densification and sphericity, which has a significant promoting effect on improving the performance of tungsten-nickel-iron powder tensile parts.

[0033] Comparative Example 1 Commercially available tungsten, nickel, and iron powders are mixed in a mass ratio of 93:5:2 to obtain a tungsten-nickel-iron mixed powder.

[0034] To verify the specific properties of the modified tungsten-nickel-iron powder obtained in this invention, its morphology and particle size were characterized, and the D50 average particle size, loose packing density, and tap density were also measured. Furthermore, the modified tungsten-nickel-iron powder obtained in this invention was applied to the preparation of tensile parts, and its effect on the properties of the tensile parts was studied. Details are as follows: 1. The modified tungsten-nickel-iron powders obtained in Examples 1-8 and the unmodified tungsten-nickel-iron mixed powder in Comparative Example 1 were subjected to SEM analysis and particle size distribution analysis. The results are as follows: Figure 1 and Figure 2 To obtain the SEM images and particle size distribution diagrams of the unmodified tungsten-nickel-iron mixed powder in Comparative Example 1, the following methods were used: Figure 1 and Figure 2 It can be seen that unmodified tungsten-nickel-iron powder has relatively irregular particle shape, uneven size distribution, and relatively rough surface.

[0035] Figure 3 and Figure 4 The images show the SEM images and particle size distribution of the modified tungsten nickel-iron powder obtained in Example 1. Figure 5 and Figure 6 The images show the SEM images and particle size distribution of the modified tungsten-nickel-iron powder obtained in Example 2. Figure 7 and Figure 8 The images show the SEM images and particle size distribution of the modified tungsten nickel-iron powder obtained in Example 3. Figure 9 and Figure 10 The images show the SEM images and particle size distribution of the modified tungsten nickel-iron powder obtained in Example 4. Figure 11 and Figure 12 The images show the SEM images and particle size distribution of the modified tungsten-nickel-iron powder obtained in Example 5. Figure 13 and Figure 14 The images show the SEM images and particle size distribution of the modified tungsten nickel-iron powder obtained in Example 6. Figure 15 and Figure 16 SEM images and particle size distribution diagrams of the modified tungsten nickel-iron powder obtained in Example 7; Figure 17 and Figure 18 SEM images and particle size distribution diagrams of the modified tungsten-nickel-iron powder obtained in Example 8 are shown. Figures 3-6 It can be seen that when the modification treatment time is 15-30 min, the particles begin to become more regularized, and the edges of some large particles become smoother, but there are still many irregularly shaped particles, and the aggregation between particles is quite obvious; through Figures 7-10 It can be seen that when the modification treatment time is 45-60 min, the regularity of the particles is further improved, most particles tend to be spherical, the surface is smoother, and the size distribution gradually becomes more uniform; through Figures 11-18 It can be seen that the particle morphology is basically stable, maintaining a relatively regular spherical shape, and the surface smoothness does not change much. However, due to long-term fusion, some particles have a slight tendency to stick together.

[0036] 2. The D50 average particle size, loose packing density, and tap density of the modified tungsten-nickel-iron powder obtained in Examples 1-8 and the unmodified tungsten-nickel-iron mixed powder in Comparative Example 1 were tested using the following methods: (1) Loose packing density test The test was conducted in accordance with GB / T 1479.3-2017 "Metal Powder Loose Packing Density Test Method", specifically using GB / T 1479.3-2017 Part 3: Vibrating Funnel Method.

[0037] (2) Tap density test The test was conducted in accordance with GB / T 5162-2021 "Metal Powder Tap Density Test Method", with a vibration frequency of 100 times / min to 300 times / min.

[0038] The test results are shown in Table 1 below: Table 1 Performance test data of tungsten-nickel-iron powder 3. Tensile parts were prepared using the modified tungsten-nickel-iron powder obtained in Examples 1-8 and the unmodified tungsten-nickel-iron mixed powder in Comparative Example 1, and their performance was tested. The method is as follows: (1) Preparation of tensile parts Tungsten-nickel-iron alloy tensile parts are prepared using powder metallurgy technology. The treated tungsten-nickel-iron powder is formed into a green blank by high-pressure molding. The green blank is then subjected to high-temperature liquid-phase sintering under a hydrogen or vacuum protective atmosphere, followed by hot forging, hot rolling and other hot working treatments. Finally, the complex tensile parts that meet the design requirements are obtained by precision machining.

[0039] (2) Tensile strength test The test was conducted according to GB / T 228.1-2021 "Metallic materials - Tensile testing - Part 1: Test method at room temperature" using a universal testing machine at a tensile speed of 5 mm / min. The test data are shown in Table 2.

[0040] Table 2 Tensile property test data of tensile specimens (3) Impact toughness test The test was conducted according to GB / T 229-2007 "Metallic Materials Charpy Impact Test Method". Specific test results are shown in Table 3. Table 3 Impact performance test data of tensile specimens Figure 19 SEM images of the alloy cross sections in tensile strength (ac) and impact toughness (ef) tests of the tensile parts prepared from the unmodified tungsten-nickel-iron mixed powder in Comparative Example 1. Figures 20-27 SEM images of the alloy cross-sections of tensile specimens prepared from the modified tungsten-nickel-iron powder of Examples 1-8 of this invention, taken during tensile strength (ac) and impact toughness (ef) tests. (The images are obtained through...) Figure 19 (Comparative Example 1) and Figure 20-27Comparative analysis of SEM cross-sectional morphology in Examples 1-8 shows that the fracture mode of the alloys prepared from the modified tungsten-nickel-iron powder has changed significantly. The alloy cross-section of Comparative Example 1 shows more porosity and brittle cleavage fracture characteristics; while the alloy cross-sections of the embodiments of this invention exhibit a denser microstructure, with a significantly increased number of dimples, larger and deeper in size, and enhanced interfacial bonding between tungsten particles and the binder phase. This indicates that the modification process effectively improves the sintering activity and microstructure uniformity of the powder, thereby simultaneously improving its ductility and toughness while achieving high strength. However, the choice of processing time is also crucial. Comparing Examples 1-8, Example 1 (high-speed fusion modification processing time of 15 min) is the optimal one.

[0041] As shown in Tables 1, 2, and 3, the high-speed fusion modification method of this invention improves the sphericity of tungsten-nickel-iron powder while reducing agglomeration. The modified tungsten-nickel-iron powder exhibits better mechanical properties and significantly improves the strength of tensile parts.

[0042] Table 4. Comparison of the properties of tungsten-nickel-iron powder and the tensile parts made from it in Example 1 and Comparative Example 1 of the present invention In the high-speed fusion modification method of tungsten-nickel-iron powder of the present invention, tungsten-nickel-iron powder with a mass ratio of tungsten, nickel, and iron of (90~98):(1~6):(1~4) is applicable. The modification temperature range is 6~12℃, the frequency is 10~40 Hz, and the modification time is 15~120 min. When the temperature and frequency are higher, the modification time can be appropriately shortened, and high-performance modified tungsten-nickel-iron powder can still be prepared.

[0043] Example 9 This embodiment describes a method for preparing modified tungsten-nickel-iron powder. The method is as follows: 1000 g of spherical tungsten-nickel-iron powder (tungsten, nickel, and iron in a mass ratio of 90:6:4) was weighed and added to the vessel of a high-speed fusion machine. Then, 10 g of binder (polyethylene glycol), 10 g of lubricant (stearate), 5 g of reinforcing agent (cerium oxide), and 5 g of antioxidant (yttrium oxide) were added to perform high-speed fusion modification treatment on the tungsten-nickel-iron powder. The high-speed fusion machine was used at a frequency of 10 Hz, a processing time of 15 min, and a processing temperature of 10~12℃. After the modification was completed, spherical modified tungsten-nickel-iron powder was obtained.

[0044] Example 10 This embodiment describes a method for preparing modified tungsten-nickel-iron powder. The method is as follows: 1000 g of spherical tungsten-nickel-iron powder (tungsten, nickel, and iron in a mass ratio of 98:1:1) was weighed and added to the vessel of a high-speed fusion machine. Then, 50 g of binder (polyvinyl alcohol), 5 g of lubricant (stearic acid), 8 g of reinforcing agent (cerium oxide), and 7 g of antioxidant (yttrium oxide) were added to perform high-speed fusion modification treatment on the tungsten-nickel-iron powder. The high-speed fusion machine was used at a frequency of 30 Hz, a processing time of 15 min, and a processing temperature of 10~12℃. After the modification was completed, spherical modified tungsten-nickel-iron powder was obtained.

[0045] Example 11 This embodiment describes a method for preparing modified tungsten-nickel-iron powder. The method is as follows: 1000 g of spherical tungsten-nickel-iron powder (tungsten, nickel, and iron in a mass ratio of 95:3:2) was weighed and added to the vessel of a high-speed fusion machine. Then, 20 g of binder (polyvinyl alcohol), 30 g of lubricant (stearic acid), 15 g of reinforcing agent (cerium oxide), and 5 g of antioxidant (yttrium oxide) were added to perform high-speed fusion modification treatment on the tungsten-nickel-iron powder. The high-speed fusion machine was used at a processing frequency of 40 Hz, a processing time of 15 min, and a processing temperature of 10~12℃. After the modification was completed, spherical modified tungsten-nickel-iron powder was obtained.

[0046] Example 12 This embodiment describes a method for preparing modified tungsten-nickel-iron powder. The method is as follows: 1000 g of spherical tungsten-nickel-iron powder (tungsten, nickel, and iron in a mass ratio of 95:3:2) was weighed and added to the vessel of a high-speed fusion machine. Then, 25 g of binder (polyethylene glycol), 15 g of lubricant (stearate), 3 g of reinforcing agent (cerium oxide), and 2 g of antioxidant (yttrium oxide) were added to perform high-speed fusion modification treatment on the tungsten-nickel-iron powder. The high-speed fusion machine was used at a frequency of 40 Hz, a processing time of 15 min, and a processing temperature of 10~12℃. After the modification was completed, spherical modified tungsten-nickel-iron powder was obtained.

[0047] In summary, the high-speed fusion modification method of the present invention has a significant effect on improving the performance of tungsten nickel-iron powder. Furthermore, the tensile parts prepared by the modified tungsten nickel-iron powder obtained by the present invention exhibit better strength and toughness, which can meet the requirements of specific processes and applications, and has important application value in high-end fields (such as aerospace).

[0048] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any way. Any simple modifications, alterations, and equivalent changes made to the above embodiments based on the inventive essence shall still fall within the protection scope of the present invention.

Claims

1. A method for preparing modified tungsten-nickel-iron powder, characterized in that, The method is as follows: With the help of binders, lubricants and additives, tungsten nickel iron powder is treated by a high-speed fusion modification method to obtain modified tungsten nickel iron powder. The tungsten-nickel-iron powder has a particle size of 3~5 µm, and the mass ratio of tungsten, nickel and iron is (90~98):(1~6):(1~4). The binder is polyvinyl alcohol and / or polyethylene glycol; the lubricant is stearic acid and / or stearate; the additive consists of a reinforcing agent and an antioxidant, wherein the reinforcing agent is cerium oxide and the antioxidant is yttrium oxide; The high-speed fusion modification method uses a high-speed fusion machine for modification, the temperature during high-speed fusion modification is 6~12℃, the frequency during high-speed fusion modification is 10~40 Hz, and the high-speed fusion modification time is 15~120 min.

2. The method for preparing modified tungsten-nickel-iron powder according to claim 1, characterized in that, The amount of the binder is 1 to 5 wt% of the mass of the tungsten nickel iron powder.

3. The method for preparing modified tungsten-nickel-iron powder according to claim 1, characterized in that, The amount of the lubricant used is 0.5~3wt% of the mass of the tungsten nickel iron powder.

4. The method for preparing modified tungsten-nickel-iron powder according to claim 1, characterized in that, The additive consists of a reinforcing agent and an antioxidant, and is used in an amount of 0.5 to 2 wt% of the tungsten nickel iron powder.

5. The method for preparing modified tungsten-nickel-iron powder according to claim 4, characterized in that, The amount of the reinforcing agent is 0.3 to 1.5 wt% of the mass of the tungsten nickel iron powder; the amount of the antioxidant is 0.2 to 0.8 wt% of the mass of the tungsten nickel iron powder.

6. A modified tungsten-nickel-iron powder, characterized in that, The modified tungsten-nickel-iron powder, prepared by any one of claims 1-5, has a sphericity of 93%.

7. The application of the modified tungsten-nickel-iron powder according to claim 6 in the preparation of stretched parts, characterized in that, The tensile strength of the tensioned member reaches 950 MPa or more.

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