A method for preparing high bearing anti-friction self-lubricating carburized layer on steel surface by equivalent rare earth plasma

Abstract

A method for preparing a high-load-bearing, friction-reducing, and self-lubricating carburized layer on the surface of steel using equivalent rare-earth plasma is disclosed. This method addresses the problem of high-speed, heavy-load, or heavy-load fatigue adhesion in existing steel moving parts. The invention utilizes equivalent rare-earth plasma carburizing technology to prepare a high-load-bearing, friction-reducing, and self-lubricating carburized layer on the surface of metal components. The equivalent rare-earth plasma carburizing technology forms a martensite layer on the surface of the carburized layer, with Fe atoms dispersed on it and encapsulated by GLC or DLC. 2‑3 C or Fe 2‑3 The N-structured carburized layer. GLC or DLC structures possess friction-reducing and self-lubricating capabilities, while significantly reducing wear rates compared to conventional carburizing treatments, and greatly improving the corrosion resistance of the carburized layer surface. It can be applied to moving parts with any carburized layer thickness design requirements, solving problems such as high-speed heavy-load adhesion and heavy-load fatigue adhesion in moving parts, and has wide engineering applications.

Description

Technical Field

[0001] This invention relates to a method for preparing a carburized layer on the surface of steel. Background Technology

[0002] Key moving components, such as bearings and gears, are the core of equipment, determining its main functions and reflecting its lifespan and reliability. Their failure can lead to catastrophic consequences. The failure mode is fatigue, which originates from the surface layer. Heat treatment and surface modification endow key components with lifespan and reliability. As the service conditions and environments of moving components in high-end equipment become increasingly harsh, such as high-speed, heavy-load service in high-temperature and oxygen-containing environments, the requirements for the surface performance of components are becoming increasingly stringent. Typically, heavy-load resistant moving components require a thicker hardened layer, hence the use of carburizing. However, during service, gears and bearings that have undergone gas carburizing experience scuffing due to lack of oil lubrication at the contact surfaces, as well as the appearance of microcracks or pitting, in environments ranging from room temperature to 600°C and containing oxygen. This scuffing, known as high-speed heavy-load scuffing and heavy-load fatigue scuffing, severely inhibits the improvement of moving component lifespan and reliability.

[0003] Existing surface treatment technologies for steel components, such as conventional gas carburizing, can improve load-bearing capacity, but the improvement is limited; surface coating technology can achieve surface friction reduction and self-lubrication, but the film-substrate adhesion is poor and it is not resistant to heavy loads; plasma low-temperature thermal diffusion technology can obtain a shallow diffusion layer and cannot achieve heavy load resistance; other surface treatment technologies also have their own advantages and disadvantages. Therefore, the surface modification layers obtained by existing technologies on the surface of steel moving parts cannot solve the problem that moving parts operating in environments with ambient temperature to 600℃ and oxygen content are prone to high-speed heavy-load adhesion or heavy-load fatigue adhesion. Summary of the Invention

[0004] In order to solve the problem that existing steel moving parts are prone to high-speed heavy-load adhesion or heavy-load fatigue adhesion, this invention proposes a method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on the surface of steel using equivalent rare-earth plasma.

[0005] The present invention describes a method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on a steel surface using equivalent rare-earth plasma, which is carried out according to the following steps:

[0006] 1. Clean the metal components to remove surface oil and dirt;

[0007] 2. The metal components are placed in a plasma carburizing furnace for equivalent rare earth plasma carburizing treatment.

[0008] The process of equivalent rare earth plasma carburizing treatment is as follows: Carrier gas is introduced into the plasma carburizing furnace at a pressure lower than the carburizing gas pressure to raise the furnace temperature to the carburizing temperature; after reaching the carburizing temperature, carburizing begins. During the carburizing process, carrier gas and carburizing gas are simultaneously introduced into the plasma multi-element co-carburizing furnace to achieve a carbon concentration of 1.0-1.8 wt.% on the surface of the metal component. Rare earth carburizing agent is introduced into the plasma carburizing furnace through the carrier gas. The carburizing gas pressure is adjusted to 200-600 Pa, and the current density is 1×10⁻⁶ Pa. -3 -1×10 -2 A / cm 2 The carburized layer on the surface of the metal component reaches the target thickness.

[0009] Third, the carburized components are quenched to complete the process;

[0010] In step three, the outermost layer of the high-load-bearing, friction-reducing, wear-resistant, and self-lubricating functional layer is mainly composed of martensite with Fe atoms dispersed on it and encapsulated by GLC (graphite-like carbon) or DLC (diamond-like carbon). 2-3 C or Fe 2-3 N or Fe 2-3 A structural infiltration layer composed of C and N (GLC@Fe) 2-3 C, GLC@Fe 2-3 N, DLC@Fe 2-3 C, DLC@Fe 2-3 N, GLC@Fe 2-3 C,N,DLC@Fe 2-3 (C,N), the near-surface structure consists of diffusely distributed carbide + martensite, nitride + martensite, or carbide + martensite.

[0011] The principle and beneficial effects of this invention are as follows:

[0012] 1. This invention prepares a carburized layer with high load-bearing capacity, friction reduction, and self-lubrication on the surface of metal components using equivalent rare-earth plasma carburizing technology. The equivalent rare-earth plasma carburizing technology first forms a dispersed carbide layer (Fe...) 2-3 C) / Nitrogen compounds (Fe) 2-3 N) / carbonitrides (Fe) 2-3 C,N) carburization layer, with the extension of carburization time, GLC or DLC in Fe 2-3 C or Fe 2-3 N or Fe 2-3 In-situ growth of C and N on the surface, ultimately forming Fe atoms dispersed on the surface of the carburized layer, encapsulated by GLC or DLC. 2-3 C, Fe 2-3 N or Fe 2-3The structure is composed of C and N infiltration layers. The combined plasma and rare earth processes improve the diffusion coefficient and carbon concentration on the component surface (the carbon concentration on conventional carburized surfaces can generally only reach below 1.0 wt.%). Rare earth infiltration inhibits the precipitation of grain boundary carbides and promotes the dispersed precipitation of carbides within the grains. The combined effect promotes GLC@Fe 2- 3C, DLC@Fe 2-3 C, GLC@Fe 2-3 N, DLC@Fe 2-3 N, GLC@Fe 2-3 C,N,DLC@Fe 2-3 The formation of C and N. The GLC or DLC structure has the ability to reduce friction and self-lubricate. The friction coefficient of the carburized layer is as low as below 0.1 at room temperature and as low as 0.1~0.2 at high temperature of 400-600℃. At the same time, the wear rate is significantly reduced compared with conventional carburizing treatment, and the corrosion resistance of the carburized layer surface is greatly improved.

[0013] 2. The present invention obtains a near-surface microstructure of metal components consisting of dispersed carbides / nitrides and martensite, which gives the carburized layer a high load-bearing capacity and a gradient hardness distribution, with the hardness of the outermost layer reaching 800 HV. 0.1 In addition, the thickness of the carburized layer is controllable, which can be applied to moving parts with any carburized layer thickness design requirements. It can solve the problems of high-speed heavy-load adhesion and heavy-load fatigue adhesion that are prone to occur in moving parts, and has a wide range of engineering applications. Attached Figure Description

[0014] Figure 1 An optical micrograph of the microstructure of the carburized layer prepared in Example 1;

[0015] Figure 2 Micrograph of the functional structure GLC@Fe3C in the carburized layer prepared in Example 1;

[0016] Figure 3 The Raman spectrum of the surface layer of the carburized layer prepared in Example 1;

[0017] Figure 4 The hardness distribution curve of the carburized layer prepared in Example 1;

[0018] Figure 5 The friction coefficient-time curve of the carburized layer prepared in Example 1;

[0019] Figure 6 The graph shows the friction and wear curves of the carburized layer of the Aermet100 steel metal component in Example 2 at 450 ℃, 500 ℃, and 550 ℃. Detailed Implementation

[0020] The technical solution of the present invention is not limited to the specific embodiments listed below, but also includes any reasonable combination of the specific embodiments.

[0021] Specific Implementation Method 1: This implementation method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on the surface of steel using equivalent rare-earth plasma is carried out according to the following steps:

[0022] 1. Clean the metal components to remove surface oil and dirt;

[0023] 2. The metal components are placed in a plasma carburizing furnace for equivalent rare earth plasma carburizing treatment.

[0024] The process of equivalent rare earth plasma carburizing treatment is as follows: Carrier gas is introduced into the plasma carburizing furnace at a pressure lower than the carburizing gas pressure to raise the furnace temperature to the carburizing temperature; after reaching the carburizing temperature, carburizing begins. During the carburizing process, carrier gas and carburizing gas are simultaneously introduced into the plasma multi-element co-carburizing furnace to achieve a carbon concentration of 1.0-1.8 wt.% on the surface of the metal component. Rare earth carburizing agent is introduced into the plasma carburizing furnace through the carrier gas. The carburizing gas pressure is adjusted to 200-600 Pa, and the current density is 1×10⁻⁶ Pa. -3 -1×10 -2 A / cm 2 The carburized layer on the surface of the metal component reaches the target thickness.

[0025] Third, the carburized components are quenched to complete the process;

[0026] In step three, the outermost layer of the high-load-bearing, friction-reducing, wear-resistant, and self-lubricating functional layer is mainly composed of martensite with Fe atoms dispersed on it and encapsulated by GLC (graphite-like carbon) or DLC (diamond-like carbon). 2-3 C or Fe 2-3 N or Fe 2-3 A structural infiltration layer composed of C and N (GLC@Fe) 2-3 C, GLC@Fe 2-3 N, DLC@Fe 2-3 C, DLC@Fe 2-3 N, GLC@Fe 2-3 C,N,DLC@Fe 2-3 (C,N), the near-surface structure consists of diffusely distributed carbide + martensite, nitride + martensite, or carbide + martensite.

[0027] This embodiment has the following beneficial effects:

[0028] 1. In this embodiment, a carburized layer with high load-bearing capacity, friction reduction, and self-lubrication is prepared on the surface of a metal component using equivalent rare-earth plasma carburizing technology. The equivalent rare-earth plasma carburizing technology first forms a dispersed carbide layer (Fe...)2-3 C) / Nitrogen compounds (Fe) 2-3 N) / carbonitrides (Fe) 2-3 C,N) carburization layer, with the extension of carburization time, GLC or DLC in Fe 2-3 C or Fe 2-3 N or Fe 2-3 In-situ growth of C and N on the surface, ultimately forming Fe atoms dispersed on the surface of the carburized layer, encapsulated by GLC or DLC. 2-3 C, Fe 2-3 N or Fe 2-3 The structure is composed of C and N infiltration layers. The combined plasma and rare earth processes improve the diffusion coefficient and carbon concentration on the component surface (the carbon concentration on conventional carburized surfaces can generally only reach below 1.0 wt.%). Rare earth infiltration inhibits the precipitation of grain boundary carbides and promotes the dispersed precipitation of carbides within the grains. The combined effect promotes GLC@Fe 2-3 C, DLC@Fe 2-3 C, GLC@Fe 2-3 N, DLC@Fe 2-3 N, GLC@Fe 2-3 C,N,DLC@Fe 2-3 The formation of C and N. The GLC or DLC structure has the ability to reduce friction and self-lubricate. The friction coefficient of the carburized layer is as low as below 0.1 at room temperature and as low as 0.1~0.2 at high temperature of 400-600℃. At the same time, the wear rate is significantly reduced compared with conventional carburizing treatment, and the corrosion resistance of the carburized layer surface is greatly improved.

[0029] 2. In this embodiment, the near-surface microstructure of the metal component consists of dispersed carbides / nitrides and martensite, resulting in a carburized layer with high load-bearing capacity and a gradient hardness distribution, with the outermost layer reaching a hardness of 800 HV. 0.1 In addition, the thickness of the carburized layer is controllable, which can be applied to moving parts with any carburized layer thickness design requirements. It can solve the problems of high-speed heavy-load adhesion and heavy-load fatigue adhesion that are prone to occur in moving parts, and has a wide range of engineering applications.

[0030] Specific Implementation Method Two: This implementation method differs from Specific Implementation Method One in that: the metal component mentioned in step one is carbon structural steel, alloy structural steel, bearing steel or gear steel; the metal component is a quenched and tempered metal component, an annealed metal component, a quenched and tempered metal component with a carburized layer or an annealed metal component with a carburized layer.

[0031] Specific Implementation Method 3: This implementation method differs from Specific Implementation Method 1 or 2 in that the carrier gas in step 2 is one or a mixture of several of the following in any proportion: argon, hydrogen, nitrogen, vaporized methanol, and vaporized ethanol.

[0032] Specific Implementation Method Four: This implementation method differs from one of Specific Implementation Methods One to Three in that the carburizing gas mentioned in step two is acetylene, propane, acetone, methane, carbon monoxide, carbon dioxide, ethyl acetate, or benzene.

[0033] Specific Implementation Method 5: This implementation method differs from one of the specific implementation methods 1 to 4 in that the target thickness of the carburized layer in step 2 is 0.5mm-5mm, and the thickness of the carburized layer is controlled by the carburizing time.

[0034] Specific Implementation Method Six: This implementation method differs from Specific Implementation Methods One to Five in that the quenching process in step three is water quenching, oil quenching, or gas quenching.

[0035] Specific Implementation Method Seven: This implementation method differs from Specific Implementation Methods One through Six in that the equivalent rare earth plasma carburizing process is as follows: Carrier gas is introduced into the plasma carburizing furnace at a pressure lower than the carburizing gas pressure, and the furnace is heated to 910°C. After reaching the carburizing temperature, carburizing begins. During the carburizing process, carrier gas and carburizing gas are simultaneously introduced into the plasma multi-element co-carburizing furnace, resulting in a carbon concentration of 1.4 wt.% on the surface of the metal component. Rare earth carburizing agent is introduced into the plasma carburizing furnace through the carrier gas. The carburizing gas pressure is adjusted to 400 Pa, and the current density is 1.5 × 10⁻⁶. -3 A / cm 2 The carburized layer on the surface of the metal component reaches the target thickness.

[0036] Specific Implementation Method Eight: This implementation method differs from Specific Implementation Methods One to Seven in that the equivalent rare earth plasma carburizing process is as follows: Carrier gas is introduced into the plasma carburizing furnace at a pressure lower than the carburizing gas pressure, and the furnace is heated to 910°C. After reaching the carburizing temperature, carburizing begins. During the carburizing process, carrier gas and carburizing gas are simultaneously introduced into the plasma multi-element co-carburizing furnace, resulting in a carbon concentration of 1.4 wt.% on the surface of the metal component. Rare earth carburizing agent is introduced into the plasma carburizing furnace through the carrier gas. The carburizing gas pressure is adjusted to 420 Pa, and the current density is 1.6 × 10⁻⁶. -3 A / cm 2 The carburized layer on the surface of the metal component reaches the target thickness.

[0037] Specific Implementation Method Nine: This implementation method differs from Specific Implementation Methods One through Eight in that the equivalent rare earth plasma carburizing process is as follows: Carrier gas is introduced into the plasma carburizing furnace at a pressure lower than the carburizing gas pressure, and the furnace is heated to 900°C. After reaching the carburizing temperature, carburizing begins. During the carburizing process, carrier gas and carburizing gas are simultaneously introduced into the plasma multi-element co-carburizing furnace, resulting in a carbon concentration of 1.6 wt.% on the surface of the metal component. Rare earth carburizing agent is introduced into the plasma carburizing furnace through the carrier gas. The carburizing gas pressure is adjusted to 400 Pa, and the current density is 3.2 × 10⁻⁶. -3 A / cm 2 The carburized layer on the surface of the metal component reaches the target thickness.

[0038] Specific Implementation Method Ten: This implementation method differs from Specific Implementation Methods One to Nine in that the equivalent rare earth plasma carburizing process is as follows: Carrier gas is introduced into the plasma carburizing furnace at a pressure lower than the carburizing gas pressure, and the furnace is heated to 900°C. After reaching the carburizing temperature, carburizing begins. During the carburizing process, carrier gas and carburizing gas are simultaneously introduced into the plasma multi-element co-carburizing furnace, resulting in a carbon concentration of 1.7 wt.% on the surface of the metal component. Rare earth carburizing agent is introduced into the plasma carburizing furnace through the carrier gas. The carburizing gas pressure is adjusted to 400 Pa, and the current density is 4.6 × 10⁻⁶. -3 A / cm 2 The carburized layer on the surface of the metal component reaches the target thickness.

[0039] Example 1

[0040] This embodiment describes a method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on a steel surface using equivalent rare-earth plasma, which is carried out according to the following steps:

[0041] 1. Clean the metal components to remove surface oil and dirt;

[0042] The metal component is a heat-treated metal component made of 20Cr2Ni4 steel;

[0043] 2. The metal components are placed in a plasma carburizing furnace for equivalent rare earth plasma carburizing treatment.

[0044] The process of equivalent rare earth plasma carburizing treatment is as follows: Carrier gas is introduced into the plasma carburizing furnace at a pressure lower than the carburizing gas pressure, and the furnace is heated to 910°C. After reaching the carburizing temperature, carburizing begins. During the carburizing process, carrier gas and carburizing gas are simultaneously introduced into the plasma multi-element co-carburizing furnace, so that the carbon concentration on the surface of the metal component reaches 1.4 wt.%. Rare earth carburizing agent is introduced into the plasma carburizing furnace through the carrier gas. The carburizing gas pressure is adjusted to 400 Pa, and the current density is 1.5 × 10⁻⁶. -3 A / cm 2The carburized layer on the surface of the metal component reaches the target thickness; the composition and amount of the rare earth carburizing agent refer to the national standard "Rare Earth Chemical Heat Treatment" (GB / T45983.1-2025).

[0045] The carrier gas is a mixture of argon, hydrogen, and methanol;

[0046] The carburizing gas is methane;

[0047] The target thickness of the carburized layer is 1.6 mm, and the carburizing time is 8 hours.

[0048] Third, the carburized components are quenched to complete the process;

[0049] In step three, the outermost layer of the friction-reducing, wear-resistant, and self-lubricating functional layer with high load-bearing capacity is mainly composed of Fe3C dispersed on martensite and encapsulated by GLC (graphite-like) particles. The near-surface layer is composed of dispersed carbides and martensite. The quenching treatment in step three is oil quenching.

[0050] Figure 1 An optical micrograph of the microstructure of the carburized layer prepared in Example 1; Figure 2 The image on the right is a micrograph of the functional structure GLC@Fe3C in the carburized layer prepared in Example 1; the image on the right is a magnified view of a portion thereof. Figure 3 The Raman spectrum of the surface layer of the carburized layer prepared in Example 1; Figure 4 The hardness distribution curve of the carburized layer prepared in Example 1; Figure 5 The friction coefficient-time curve of the carburized layer prepared in Example 1 is shown; the specific process of conventional carburizing is: gas carburizing at 910℃ for 8 hours, with a carbon potential Cp of 1.0. Figure 1-5 As shown, the surface microstructure is a carburized layer containing the functional structure GLC@Fe3C, while the near-surface layer consists of dispersed carbides and martensite. The surface hardness of the carburized layer reaches 850 HV, exhibiting a gradient distribution. The carburized layer thickness can reach 1.63 mm, significantly improving corrosion resistance and wear resistance, with a friction coefficient as low as 0.043. Furthermore, the corrosion current of conventional carburizing treatment is 4.56 × 10⁻⁶. -6 A / cm 2 Example 1 yielded a surface corrosion current of 1.58 × 10⁻⁶. -6 A / cm 2 Its corrosion resistance is significantly improved.

[0051] Example 2

[0052] This embodiment describes a method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on a steel surface using equivalent rare-earth plasma, which is carried out according to the following steps:

[0053] 1. Clean the metal components to remove surface oil and dirt;

[0054] The metal component is an annealed metal component made of Aermet 100 steel;

[0055] 2. The metal components are placed in a plasma carburizing furnace for equivalent rare earth plasma carburizing treatment.

[0056] The process of equivalent rare earth plasma carburizing treatment is as follows: Carrier gas is introduced into the plasma carburizing furnace at a pressure lower than the carburizing gas pressure, and the furnace is heated to 910°C. After reaching the carburizing temperature, carburizing begins. During the carburizing process, carrier gas and carburizing gas are simultaneously introduced into the plasma multi-element co-carburizing furnace, so that the carbon concentration on the surface of the metal component reaches 1.4 wt.%. Rare earth carburizing agent is introduced into the plasma carburizing furnace through the carrier gas. The carburizing gas pressure is adjusted to 420 Pa, and the current density is 1.6 × 10⁻⁶. -3 A / cm 2 The carburized layer on the surface of the metal component reaches the target thickness; the composition and amount of the rare earth carburizing agent refer to the national standard "Rare Earth Chemical Heat Treatment" (GB / T45983.1-2025).

[0057] The carrier gas is a mixture of argon, hydrogen, and methanol;

[0058] The carburizing gas is acetylene;

[0059] The target thickness of the carburized layer is 1.5 mm, and the carburizing time is 8 hours.

[0060] Third, the carburized components are quenched to complete the process;

[0061] The quenching process in step three is oil quenching.

[0062] In this embodiment, the surface hardness of the carburized layer reaches 930 HV. 0.1 The hardness is distributed in a gradient, the carburized layer thickness reaches 1.52mm, the wear resistance is greatly improved, and the friction coefficient is as low as 0.052 at room temperature. Figure 6 The graph shows the friction and wear curves of the carburized layer of the Aermet100 steel metal component in Example 2 at 450 ℃, 500 ℃, and 550 ℃. The friction coefficients of the carburized layer prepared in Example 2 at 450 ℃, 500 ℃, and 550 ℃ are 0.147, 0.125, and 0.177, respectively.

[0063] Example 3

[0064] This embodiment describes a method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on a steel surface using equivalent rare-earth plasma, which is carried out according to the following steps:

[0065] 1. Clean the metal components to remove surface oil and dirt;

[0066] The metal component is a heat-treated metal component made of M50NiL steel;

[0067] 2. The metal components are placed in a plasma carburizing furnace for equivalent rare earth plasma carburizing treatment.

[0068] The process of equivalent rare earth plasma carburizing treatment is as follows: Carrier gas is introduced into the plasma carburizing furnace at a pressure lower than the carburizing gas pressure, and the furnace is heated to 900°C. After reaching the carburizing temperature, carburizing begins. During the carburizing process, carrier gas and carburizing gas are simultaneously introduced into the plasma multi-element co-carburizing furnace, so that the carbon concentration on the surface of the metal component reaches 1.7 wt.%. Rare earth carburizing agent is introduced into the plasma carburizing furnace through the carrier gas. The carburizing gas pressure is adjusted to 400 Pa, and the current density is 4.6 × 10⁻⁶. -3 A / cm 2 The carburized layer on the surface of the metal component reaches the target thickness; the composition and amount of the rare earth carburizing agent refer to the national standard "Rare Earth Chemical Heat Treatment" (GB / T45983.1-2025).

[0069] The carrier gas is a mixture of argon, hydrogen, and methanol;

[0070] The carburizing gas is acetylene;

[0071] The target thickness of the carburized layer is 1.6 mm, and the carburizing time is 8 hours.

[0072] Third, the carburized components are quenched to complete the process;

[0073] The quenching process in step three is oil quenching.

[0074] In this embodiment, the surface hardness of the carburized layer reaches 980 HV. 0.1 The hardness is distributed in a gradient, the carburized layer thickness reaches 1.67mm, the corrosion resistance and wear resistance are significantly improved, and the friction coefficient is as low as 0.036.

[0075] Example 4

[0076] This embodiment describes a method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on a steel surface using equivalent rare-earth plasma, which is carried out according to the following steps:

[0077] 1. Clean the metal components to remove surface oil and dirt;

[0078] The metal component is a heat-treated metal component made of CSS-42L steel;

[0079] 2. The metal components are placed in a plasma carburizing furnace for equivalent rare earth plasma carburizing treatment.

[0080] The process of equivalent rare earth plasma carburizing treatment is as follows: Carrier gas is introduced into the plasma carburizing furnace at a pressure lower than the carburizing gas pressure, and the furnace is heated to 980°C. After reaching the carburizing temperature, carburizing begins. During the carburizing process, carrier gas and carburizing gas are simultaneously introduced into the plasma multi-element co-carburizing furnace, so that the carbon concentration on the surface of the metal component reaches 1.5 wt.%. Rare earth carburizing agent is introduced into the plasma carburizing furnace through the carrier gas. The carburizing gas pressure is adjusted to 460 Pa, and the current density is 5.1 × 10⁻⁶. -3 A / cm 2 The carburized layer on the surface of the metal component reaches the target thickness; the composition and amount of the rare earth carburizing agent refer to the national standard "Rare Earth Chemical Heat Treatment" (GB / T45983.1-2025).

[0081] The carrier gas is a mixture of argon, hydrogen, and methanol;

[0082] The carburizing gas is acetylene;

[0083] The target thickness of the carburized layer is 2 mm, and the carburizing time is 12 h.

[0084] Third, the carburized components are quenched to complete the process;

[0085] The quenching process in step three is oil quenching.

[0086] In this embodiment, the surface hardness of the carburized layer reaches 1050 HV. 0.1 The hardness is distributed in a gradient, the carburized layer thickness reaches 2.06mm, the corrosion resistance and wear resistance are significantly improved, the friction coefficient is as low as 0.052 at room temperature and as low as 0.11-0.19 at high temperature of 400-600℃.

[0087] Example 5

[0088] This embodiment describes a method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on a steel surface using equivalent rare-earth plasma, which is carried out according to the following steps:

[0089] 1. Clean the metal components to remove surface oil and dirt;

[0090] The metal component is an annealed metal component made of S280 steel;

[0091] 2. The metal components are placed in a plasma carburizing furnace for equivalent rare earth plasma carburizing treatment.

[0092] The process of equivalent rare earth plasma carburizing treatment is as follows: Carrier gas is introduced into the plasma carburizing furnace at a pressure lower than the carburizing gas pressure, and the furnace temperature is raised to 960°C. After reaching the carburizing temperature, carburizing begins. During the carburizing process, carrier gas and carburizing gas are simultaneously introduced into the plasma multi-element co-carburizing furnace, resulting in a carbon concentration of 1.6 wt.% on the surface of the metal component. Rare earth carburizing agent is introduced into the plasma carburizing furnace through the carrier gas. The carburizing gas pressure is adjusted to 480 Pa, and the current density is 4.1 × 10⁻⁶. -3 A / cm 2 The carburized layer on the surface of the metal component reaches the target thickness; the composition and amount of the rare earth carburizing agent refer to the national standard "Rare Earth Chemical Heat Treatment" (GB / T45983.1-2025).

[0093] The carrier gas is a mixture of argon, hydrogen, and methanol;

[0094] The carburizing gas is acetylene;

[0095] The target thickness of the carburized layer is 1.6 mm, and the carburizing time is 10 h.

[0096] Third, the carburized components are quenched to complete the process;

[0097] The quenching process in step three is oil quenching.

[0098] In this embodiment, the surface hardness of the carburized layer reaches 900 HV. 0.1 The hardness is distributed in a gradient, the carburized layer thickness reaches 1.62mm, the corrosion resistance and wear resistance are significantly improved, and the friction coefficient is as low as 0.058.

[0099] Example 6

[0100] This embodiment describes a method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on a steel surface using equivalent rare-earth plasma, which is carried out according to the following steps:

[0101] 1. Clean the metal components to remove surface oil and dirt;

[0102] The metal component is a heat-treated metal component made of 16Cr3NiWMoVNbE steel;

[0103] 2. The metal components are placed in a plasma carburizing furnace for equivalent rare earth plasma carburizing treatment.

[0104] The process of equivalent rare earth plasma carburizing treatment is as follows: Carrier gas is introduced into the plasma carburizing furnace at a pressure lower than the carburizing gas pressure, and the furnace is heated to 920°C. After reaching the carburizing temperature, carburizing begins. During the carburizing process, carrier gas and carburizing gas are simultaneously introduced into the plasma multi-element co-carburizing furnace, so that the carbon concentration on the surface of the metal component reaches 1.4 wt.%. Rare earth carburizing agent is introduced into the plasma carburizing furnace through the carrier gas. The carburizing gas pressure is adjusted to 420 Pa, and the current density is 2.8 × 10⁻⁶. -3 A / cm 2 The carburized layer on the surface of the metal component reaches the target thickness; the composition and amount of the rare earth carburizing agent refer to the national standard for a mixture of argon, hydrogen and methanol.

[0105] The carburizing gas is acetylene;

[0106] The target thickness of the carburized layer is 2.5 mm, and the carburizing time is 25 h;

[0107] Third, the carburized components are quenched to complete the process;

[0108] The quenching process in step three is oil quenching.

[0109] In this embodiment, the surface hardness of the carburized layer reaches 860 HV. 0.1 The hardness is distributed in a gradient, the carburized layer thickness reaches 2.58mm, the corrosion resistance and wear resistance are significantly improved, and the friction coefficient is as low as 0.055.

[0110] Example 7

[0111] This embodiment describes a method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on a steel surface using equivalent rare-earth plasma, which is carried out according to the following steps:

[0112] 1. Clean the metal components to remove surface oil and dirt;

[0113] The metal component is a heat-treated metal component made of 18Cr2Ni4W steel;

[0114] 2. The metal components are placed in a plasma carburizing furnace for equivalent rare earth plasma carburizing treatment.

[0115] The process of equivalent rare earth plasma carburizing treatment is as follows: Carrier gas is introduced into the plasma carburizing furnace at a pressure lower than the carburizing gas pressure, and the furnace temperature is raised to 890°C. After reaching the carburizing temperature, carburizing begins. During the carburizing process, carrier gas and carburizing gas are simultaneously introduced into the plasma multi-element co-carburizing furnace, resulting in a carbon concentration of 1.4 wt.% on the surface of the metal component. Rare earth carburizing agent is introduced into the plasma carburizing furnace through the carrier gas. The carburizing gas pressure is adjusted to 360 Pa, and the current density is 2 × 10⁻⁶. -3 A / cm2 The carburized layer on the surface of the metal component reaches the target thickness; the composition and amount of the rare earth carburizing agent refer to the national standard "Rare Earth Chemical Heat Treatment" (GB / T45983.1-2025).

[0116] The carrier gas is a mixture of nitrogen, hydrogen, and methanol;

[0117] The carburizing gas is acetylene;

[0118] The target thickness of the carburized layer is 2.2 mm, and the carburizing time is 12 h.

[0119] Third, the carburized components are quenched to complete the process;

[0120] The quenching process in step three is oil quenching.

[0121] In this embodiment, the surface hardness of the carburized layer reaches 820 HV. 0.1 The hardness is distributed in a gradient, the carburized layer thickness reaches 2.23mm, the corrosion resistance and wear resistance are significantly improved, and the friction coefficient is as low as 0.046.

[0122] Example 8

[0123] This embodiment describes a method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on a steel surface using equivalent rare-earth plasma, which is carried out according to the following steps:

[0124] 1. Clean the metal components to remove surface oil and dirt;

[0125] The metal component is a heat-treated metal component made of 18CrNiMo7-6 steel;

[0126] 2. The metal components are placed in a plasma carburizing furnace for equivalent rare earth plasma carburizing treatment.

[0127] The process of equivalent rare earth plasma carburizing treatment is as follows: Carrier gas is introduced into the plasma carburizing furnace at a pressure lower than the carburizing gas pressure, and the furnace temperature is raised to 930°C. After reaching the carburizing temperature, carburizing begins. During the carburizing process, carrier gas and carburizing gas are simultaneously introduced into the plasma multi-element co-carburizing furnace, resulting in a carbon concentration of 1.6 wt.% on the surface of the metal component. Rare earth carburizing agent is introduced into the plasma carburizing furnace through the carrier gas. The carburizing gas pressure is adjusted to 450 Pa, and the current density is 2.6 × 10⁻⁶. -3 A / cm 2 The carburized layer on the surface of the metal component reaches the target thickness; the composition and amount of the rare earth carburizing agent refer to the national standard "Rare Earth Chemical Heat Treatment" (GB / T45983.1-2025).

[0128] The carrier gas is a mixture of argon, hydrogen, and methanol;

[0129] The carburizing gas is acetylene;

[0130] The target thickness of the carburized layer is 1.8 mm, and the carburizing time is 8 hours.

[0131] Third, the carburized components are quenched to complete the process;

[0132] The quenching process in step three is oil quenching.

[0133] In this embodiment, the surface hardness of the carburized layer reaches 890 HV. 0.1 The hardness is distributed in a gradient, the carburized layer thickness reaches 1.84mm, the corrosion resistance and wear resistance are significantly improved, and the friction coefficient is as low as 0.049.

[0134] Example 9

[0135] This embodiment describes a method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on a steel surface using equivalent rare-earth plasma, which is carried out according to the following steps:

[0136] 1. Clean the metal components to remove surface oil and dirt;

[0137] The metal component is a heat-treated metal component made of M50 steel;

[0138] 2. The metal components are placed in a plasma carburizing furnace for equivalent rare earth plasma carburizing treatment.

[0139] The process of equivalent rare earth plasma carburizing treatment is as follows: Carrier gas is introduced into the plasma carburizing furnace at a pressure lower than the carburizing gas pressure, and the furnace is heated to 900°C. After reaching the carburizing temperature, carburizing begins. During the carburizing process, carrier gas and carburizing gas are simultaneously introduced into the plasma multi-element co-carburizing furnace, so that the carbon concentration on the surface of the metal component reaches 1.6 wt.%. Rare earth carburizing agent is introduced into the plasma carburizing furnace through the carrier gas. The carburizing gas pressure is adjusted to 400 Pa, and the current density is 3.2 × 10⁻⁶. -3 A / cm 2 The carburized layer on the surface of the metal component reaches the target thickness; the composition and amount of the rare earth carburizing agent refer to the national standard "Rare Earth Chemical Heat Treatment" (GB / T45983.1-2025).

[0140] The carrier gas is a mixture of nitrogen, hydrogen, and methanol;

[0141] The carburizing gas is acetylene;

[0142] The target thickness of the carburized layer is 1.3 mm, and the carburizing time is 6 hours.

[0143] Third, the carburized components are quenched to complete the process;

[0144] The quenching process in step three is oil quenching.

[0145] In this embodiment, the surface hardness of the carburized layer reaches 960 HV. 0.1 The hardness is distributed in a gradient, the carburized layer thickness reaches 1.33mm, the corrosion resistance and wear resistance are significantly improved, and the friction coefficient is as low as 0.043.

Claims

1. A method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on the surface of steel using equivalent rare-earth plasma, characterized in that: The method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on the surface of steel using equivalent rare-earth plasma is carried out according to the following steps:

1. Clean the metal components to remove surface oil and dirt; 2. The metal components are placed in a plasma carburizing furnace for equivalent rare earth plasma carburizing treatment. The process of equivalent rare earth plasma carburizing treatment is as follows: Carrier gas is introduced into the plasma carburizing furnace at a pressure lower than the carburizing gas pressure to raise the furnace temperature to the carburizing temperature; after reaching the carburizing temperature, carburizing begins. During the carburizing process, carrier gas and carburizing gas are simultaneously introduced into the plasma multi-element co-carburizing furnace to achieve a carbon concentration of 1.0-1.8 wt.% on the surface of the metal component. Rare earth carburizing agent is introduced into the plasma carburizing furnace through the carrier gas. The carburizing gas pressure is adjusted to 200-600 Pa, and the current density is 1×10⁻⁶ Pa. -3 -1×10 -2 A / cm 2 The carburized layer on the surface of the metal component reaches the target thickness. Third, the carburized components are quenched to complete the process; Step 3 yields a high-load-bearing, friction-reducing, wear-resistant, and self-lubricating functional layer. The outermost layer consists of Fe atoms dispersed on martensite and encapsulated by GLC or DLC. 2-3 C, Fe 2-3 N or Fe 2-3 The structured infiltration layer is composed of C and N, and the near-surface structure consists of diffusely distributed carbide + martensite, nitride + martensite, or carbide + martensite.

2. The method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on the surface of steel using equivalent rare-earth plasma according to claim 1, characterized in that: The metal component mentioned in step one is carbon structural steel, alloy structural steel, bearing steel or gear steel; the metal component is a quenched and tempered metal component, an annealed metal component, a quenched and tempered metal component with a carburized layer or an annealed metal component with a carburized layer.

3. The method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on the surface of steel using equivalent rare-earth plasma according to claim 1, characterized in that: The carrier gas in step two is one or a mixture of several of the following in any proportion: argon, hydrogen, nitrogen, vaporized methanol, and vaporized ethanol.

4. The method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on the surface of steel using equivalent rare-earth plasma according to claim 1, characterized in that: The carburizing gas mentioned in step two is acetylene, propane, acetone, methane, carbon monoxide, carbon dioxide, ethyl acetate, or benzene.

5. The method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on the surface of steel using equivalent rare-earth plasma according to claim 1, characterized in that: The target thickness of the carburized layer in step two is 0.5mm-5mm, and the thickness of the carburized layer is controlled by the carburizing time.

6. The method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on the surface of steel using equivalent rare-earth plasma according to claim 1, characterized in that: In step three, the quenching process can be water quenching, oil quenching, or gas quenching.

7. The method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on the surface of steel using equivalent rare-earth plasma according to claim 1, characterized in that: The process of equivalent rare earth plasma carburizing treatment is as follows: Carrier gas is introduced into the plasma carburizing furnace at a pressure lower than the carburizing gas pressure, and the furnace is heated to 910°C. After reaching the carburizing temperature, carburizing begins. During the carburizing process, carrier gas and carburizing gas are simultaneously introduced into the plasma multi-element co-carburizing furnace, so that the carbon concentration on the surface of the metal component reaches 1.4 wt.%. Rare earth carburizing agent is introduced into the plasma carburizing furnace through the carrier gas. The carburizing gas pressure is adjusted to 400 Pa, and the current density is 1.5 × 10⁻⁶. -3 A / cm 2 The carburized layer on the surface of the metal component reaches the target thickness.

8. The method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on the surface of steel using equivalent rare-earth plasma according to claim 1, characterized in that: The process of equivalent rare earth plasma carburizing treatment is as follows: Carrier gas is introduced into the plasma carburizing furnace at a pressure lower than the carburizing gas pressure, and the furnace is heated to 910°C. After reaching the carburizing temperature, carburizing begins. During the carburizing process, carrier gas and carburizing gas are simultaneously introduced into the plasma multi-element co-carburizing furnace, so that the carbon concentration on the surface of the metal component reaches 1.4 wt.%. Rare earth carburizing agent is introduced into the plasma carburizing furnace through the carrier gas. The carburizing gas pressure is adjusted to 420 Pa, and the current density is 1.6 × 10⁻⁶. -3 A / cm 2 The carburized layer on the surface of the metal component reaches the target thickness.

9. The method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on the surface of steel using equivalent rare-earth plasma according to claim 1, characterized in that: The process of equivalent rare earth plasma carburizing treatment is as follows: Carrier gas is introduced into the plasma carburizing furnace at a pressure lower than the carburizing gas pressure, and the furnace is heated to 900°C. After reaching the carburizing temperature, carburizing begins. During the carburizing process, carrier gas and carburizing gas are simultaneously introduced into the plasma multi-element co-carburizing furnace, so that the carbon concentration on the surface of the metal component reaches 1.6 wt.%. Rare earth carburizing agent is introduced into the plasma carburizing furnace through the carrier gas. The carburizing gas pressure is adjusted to 400 Pa, and the current density is 3.2 × 10⁻⁶. -3 A / cm 2 The carburized layer on the surface of the metal component reaches the target thickness.

10. The method for preparing a high-load-bearing, friction-reducing, self-lubricating carburized layer on the surface of steel using equivalent rare-earth plasma according to claim 1, characterized in that: The process of equivalent rare earth plasma carburizing treatment is as follows: a carrier gas is introduced into the plasma carburizing furnace at a pressure lower than the carburizing gas pressure, and the plasma carburizing furnace is heated to 900°C; after reaching the carburizing temperature, carburizing begins. During the carburizing process, both the carrier gas and the carburizing gas are simultaneously introduced into the plasma multi-element co-carburizing furnace, so that the carbon concentration on the surface of the metal component reaches 1.7 wt.%. Rare earth carburizing agent is introduced into the plasma carburizing furnace through the carrier gas, and the carburizing gas pressure is adjusted to 400 Pa and the current density to 4.6 × 10⁻⁶. -3 A / cm 2 The carburized layer on the surface of the metal component reaches the target thickness.

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