CN114196954A

CN114196954A - Composite sulfurizing layer and preparation method and application thereof

Info

Publication number: CN114196954A
Application number: CN202111482937.3A
Authority: CN
Inventors: 邵亮; 李凯; 张昕辉; 杨林; 夏广明; 张薇; 张林阳; 陈学罡; 王鹏; 张国政
Original assignee: FAW Group Corp
Current assignee: FAW Group Corp
Priority date: 2021-12-07
Filing date: 2021-12-07
Publication date: 2022-03-18

Abstract

The invention relates to a composite sulfurizing layer and a preparation method and application thereof, wherein the composite sulfurizing layer comprises a gradient sulfurizing layer and a metal sulfurizing layer which are sequentially arranged on a substrate; the gradient sulfurizing layer comprises the following components in percentage by mass: 1-35% of oxygen, 0.1-15% of sulfur and the balance of iron; the metal sulfurizing layer comprises the following components in percentage by mass: metal elements, excluding iron 0.1-2%, sulfur 0.1-9%, and the balance iron; the thickness of the gradient sulfurizing layer is 1-200 μm; the thickness of the metal sulfurizing layer is 1-5 μm. The surface performance of the transmission part is improved by adjusting the composition and the arrangement position of the composite sulfurizing layer and utilizing the synergistic enhancement effect between the composition and the arrangement position. The friction coefficient of the surface of a transmission part is obviously reduced, and the friction reducing performance is improved, so that the transmission has good wear resistance, gluing resistance and micro-pitting corrosion resistance, and the service life of the transmission is prolonged.

Description

Composite sulfurizing layer and preparation method and application thereof

Technical Field

The invention relates to the field of surface treatment, in particular to a composite sulfurizing layer and a preparation method and application thereof.

Background

At present, the speed changer is widely used in various industries to realize the regulation and control of the rotating speed in different scenes.

The CN205118188U discloses a high-low gear electric truck transmission, which belongs to the field of transmissions and structurally comprises a front shell and a rear shell, wherein the front shell and the rear shell are buckled into a transmission shell, a clutch cover is installed on the front side of the front shell, a first shaft is installed in the clutch cover, the rear end of the first shaft is connected with a second shaft in the transmission shell, a second shaft rear cover is installed on the rear end of the rear shell, the rear side of the second shaft is arranged in the second shaft rear cover, and a brake assembly is installed at the tail end of the second shaft; an intermediate shaft and a reverse gear idler shaft are arranged below the two shafts in the transmission shell. The problem of current height keep off electric freight car reduction gear ubiquitous bearing capacity low, the noise is big, select the performance of shifting poor etc. is solved, have reasonable in design, compact structure, the noise is low, shift the travelling comfort good, bearing capacity is big and characteristics such as reliability height.

CN212775454U discloses lubricated mechanism of automotive transmission impeller and derailleur casing thereof relates to automotive transmission technical field, and this automotive transmission impeller lubricated mechanism includes: the oil injection mechanism is connected with the speed changer, and one end of the oil injection mechanism, which is far away from the speed changer, is connected with an external oil pipe and is used for injecting lubricating oil in the external oil pipe into the speed changer; rotatable rabbling mechanism, install in the inside bottom of derailleur, rabbling mechanism is used for stirring oiling mechanism pours into the inside lubricating oil of derailleur, just the rabbling mechanism includes the loose axle, can realize stirring lubricating oil to the effectual mobility that increases lubricating oil prevents that lubricating oil from taking place to deposit, makes the gear lubrication even, avoids the gear local damage, helps prolonging the life of gear, ensures the normal use of derailleur.

However, when the existing transmission is used, under the alternating action of high load and impact, due to insufficient supply of lubricating oil, the friction coefficient is increased, the friction temperature is increased, and gears, shafts or gaskets of the transmission (a driving axle) are seriously abraded; when the abrasion loss is increased, gears of all gears shift, so that the gears cannot be normally meshed, and finally the gearbox is damaged.

Disclosure of Invention

In view of the problems in the prior art, an object of the present invention is to provide a composite sulfurized layer, a preparation method and an application thereof, which solve the problems of increased friction coefficient, increased friction temperature, increased abrasion loss due to the insufficient supply of lubricating oil under the action of high load and impact alternation, and the problem of gear damage caused by the abnormal meshing between gears due to the play of gears of each gear when the abrasion loss is increased due to the severe abrasion of gears, shafts or washers of a transmission (drive axle).

In order to achieve the purpose, the invention adopts the following technical scheme:

in a first aspect, the invention provides a composite sulfurizing layer, which comprises a gradient sulfurizing layer and a metal sulfurizing layer which are sequentially arranged on a substrate;

the gradient sulfurizing layer comprises the following components in percentage by mass: 1-35% of oxygen, 0.1-15% of sulfur and the balance of iron;

the metal sulfurizing layer comprises the following components in percentage by mass: metal elements, excluding iron 0.1-2%, sulfur 0.1-9%, and the balance iron;

the thickness of the gradient sulfurizing layer is 1-200 μm; the thickness of the metal sulfurizing layer is 1-5 μm.

The surface performance of the transmission part is improved by adjusting the composition and the arrangement position of the composite sulfurizing layer and utilizing the synergistic enhancement effect between the composition and the arrangement position. The friction coefficient of the surface of a transmission part is obviously reduced, and the friction reducing performance is improved, so that the transmission has good wear resistance, gluing resistance and micro-pitting corrosion resistance, and the service life of the transmission is prolonged.

In the present invention, the oxygen content in the gradient sulfurizing layer is 1 to 35% by mass, and may be, for example, 1%, 2%, 4%, 6%, 8%, 10%, 12%, 14%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, 30%, 32%, 34%, 35%, or the like, but is not limited to the above-mentioned values, and other combinations not shown in the above-mentioned range are also applicable.

In the present invention, the sulfur content in the gradient sulfide layer may be 0.1 to 15% by mass, for example, 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, or 15%, but is not limited to the above-mentioned values, and other combinations not shown in the above-mentioned range are also applicable.

In the present invention, the metal element in the metal sulfurizing layer may be 0.1 to 2% by mass, for example, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, or 2%, but is not limited to the above-mentioned numerical values, and other combinations not shown in this range are also applicable.

In the present invention, the sulfur content in the metal-sulfurized layer is 0.1 to 9% by mass, and may be, for example, 0.1%, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, or 9%, but is not limited to the above-mentioned values, and other combinations not shown in the above-mentioned range are also applicable.

In the present invention, the thickness of the gradient sulfurization layer is 1 to 200. mu.m, and may be, for example, 1. mu.m, 2. mu.m, 3. mu.m, 4. mu.m, 5. mu.m, 6. mu.m, 7. mu.m, 8. mu.m, 9. mu.m, 10. mu.m, 20. mu.m, 30. mu.m, 40. mu.m, 50. mu.m, 60. mu.m, 70. mu.m, 80. mu.m, 90. mu.m, 100. mu.m, 110. mu.m, 120. mu.m, 130. mu.m, 140. mu.m, 150. mu.m, 160. mu.m, 170. mu.m, 180. mu.m, 190. mu.m or 200. mu.m, but not limited thereto, and other combinations not recited in the range can be similarly applied.

In the present invention, the thickness of the metal-infiltrated layer is 1 to 5 μm, and may be, for example, 1 μm, 1.2 μm, 1.4 μm, 1.6 μm, 1.8 μm, 2 μm, 2.2 μm, 2.4 μm, 2.6 μm, 2.8 μm, 3 μm, 3.2 μm, 3.4 μm, 3.6 μm, 3.8 μm, 4 μm, 4.2 μm, 4.4 μm, 4.6 μm, 4.8 μm or 5 μm, but is not limited to the values mentioned above, and other combinations not mentioned in the range are also applicable.

As the preferable technical scheme of the invention, the gradient sulfurizing layer consists of ferrous sulfide, ferric sulfide, ferroferric oxide and ferric oxide;

preferably, the metal element comprises 1 or a combination of at least 2 of molybdenum, tungsten, copper, silver, zinc or manganese.

Preferably, the metal-sulfidizing layer comprises a metal sulfide.

Preferably, the metal sulfide comprises molybdenum sulfide. For example, tungsten disulfide, copper sulfide, cuprous sulfide, silver sulfide, zinc sulfide, manganese sulfide, etc. may be used.

In a preferred embodiment of the present invention, the composite sulfur-permeated layer contains micropores of 20nm or less, for example, 20nm, 19nm, 18nm, 17nm, 16nm, 15nm, 14nm, 13nm, 12nm, 11nm, 10nm, 9nm, 8nm, 7nm, 6nm, 5nm, 4nm, 3nm, 2nm, 1nm, 0.5nm, 0.1nm, 0.05nm, or 0.01nm, and the like, but not limited to the above-mentioned values, and other combinations not listed in this range are also applicable.

In the invention, the gradient sulfurizing layer with a specific composition has a close-packed hexagonal layered crystal structure, the interlaminar shear stress is small, the sliding along the close-packed surface is easy, and the plastic deformation capability is strong. In the friction process, sulfide can generate plastic rheology, the sulfide seepage layer is stressed and rolled, the sulfide seepage layer can be filled in a concave part, and the micro-convex bodies on the surface of the friction pair can reduce the surface roughness and increase the contact area through the peak clipping and valley filling effects, so that the contact stress and the friction coefficient are reduced, and the wear resistance is improved.

It was found through experiments that the coefficient of friction of the thionized layer increases with increasing time and temperature, and also decreases with increasing temperature. But the sulfurization temperature is too high (over 180 ℃), which can affect the performance of the composite layer and lead the performance of the obtained composite layer to not reach the standard; the sulfurization time is too long, which affects the production efficiency. In addition, when the transmission part works, the surface of the transmission part slides and rolls, the working condition is complex, a single-layer sulfurizing layer is easy to wear and fall off, and the durability is poor. And the gradient sulfurizing layer has strong adhesive force, and sulfur can migrate inwards when the surface is rolled to form a sulfide layer again, so that the wear-resisting effect is further achieved. Therefore, the thickness of the gradient sulfurizing layer is 1-200 μm.

The micro-aperture of the composite sulfurizing layer is less than or equal to 20nm, and the sulfurizing layer has a loose and porous structure, so that a lubricating medium is easy to store, a lubricating oil film is formed, and the surface wear resistance is improved. However, if the pore diameter is too large, the wear resistance of the sulfurized layer will be reduced, and the sulfurized layer is liable to wear and fall off.

The metal sulfurizing layer is added on the surface of the gradient sulfurizing layer, so that the seizure resistance of the sulfurizing layer is improved, the problem of adhesive wear caused by the puncture of an oil film on the surface of a transmission mating part under the extremely severe conditions of high rotating speed or high load is solved, and the service life of the part is prolonged. Therefore, the metal sulfurization layer is 1-5 μm. When the thickness of the metal sulfurizing layer is more than 5 μm, the metal sulfurizing layer falls off due to the attenuation of the bonding strength, so that the performance of the composite sulfurizing layer is remarkably reduced.

In a second aspect, the present invention provides a method for preparing the composite sulfurizing layer according to the first aspect, comprising:

firstly, a piece to be processed is provided with a gradient sulfurizing layer by glow discharge, and then a metal sulfurizing layer is arranged by sputtering.

As a preferable embodiment of the present invention, the glow discharge includes a first evacuation, a ventilation, a second evacuation, and a temperature rise, which are performed in this order.

In a preferred embodiment of the present invention, the end point of the first evacuation is an absolute vacuum degree of 10Pa or less, and may be, for example, 10Pa, 9Pa, 8Pa, 7Pa, 6Pa, 5Pa, 4Pa, 3Pa, 2Pa or 1Pa, but is not limited to the above-mentioned values, and other combinations not mentioned in the above range are also applicable.

Preferably, the aeration is into a sulfurizing atmosphere.

Preferably, the sulfurizing atmosphere comprises hydrogen sulfide, hydrogen and an inert gas.

In a preferred embodiment of the present invention, the end point of the second evacuation is an absolute vacuum degree of 50 to 60Pa, and may be, for example, 50Pa, 51Pa, 52Pa, 53Pa, 54Pa, 55Pa, 56Pa, 57Pa, 58Pa, 59Pa, or 60Pa, but is not limited to the above-mentioned values, and other combinations not shown in the above range are also applicable.

Preferably, the temperature rise end point is 160-.

Preferably, the degree of vacuum in the furnace during sputtering is less than 0.0007Pa, and may be, for example, 0.0006Pa, 0.0005Pa, 0.0004Pa, 0.0003Pa, 0.0002Pa, or 0.0001Pa, etc., but not limited to the values listed, and other combinations not listed within this range are also applicable.

Preferably, the working gas for sputtering comprises an inert gas and/or nitrogen.

Preferably, the pressure of the sputtering is 1 to 7Pa, and may be, for example, 1Pa, 2Pa, 3Pa, 4Pa, 5Pa, 6Pa, 7Pa, or the like, but is not limited to the recited values, and other combinations not recited in this range are also applicable.

Preferably, the sputtering power is 90-320W, for example, 90W, 100W, 110W, 120W, 130W, 140W, 150W, 160W, 170W, 180W, 190W, 200W, 210W, 220W, 230W, 240W, 250W, 260W, 270W, 280W, 290W, 300W, 310W or 320W, etc., but is not limited to the values listed, and other combinations not listed in this range are also applicable.

Preferably, the sputtering time is 1 to 3 hours, and may be, for example, 1 hour, 1.1 hour, 1.2 hours, 1.3 hours, 1.4 hours, 1.5 hours, 1.6 hours, 1.7 hours, 1.8 hours, 1.9 hours, 2 hours, 2.1 hours, 2.2 hours, 2.3 hours, 2.4 hours, 2.5 hours, 2.6 hours, 2.7 hours, 2.8 hours, 2.9 hours, or 3 hours, etc., but is not limited to the values listed, and other combinations not listed in this range are also applicable.

Preferably, the temperature in the furnace during sputtering is less than 180 ℃, and may be, for example, 170 ℃, 160 ℃, 150 ℃, 140 ℃, 130 ℃, 120 ℃, 110 ℃, 100 ℃, 90 ℃, 80 ℃, 70 ℃, 60 ℃, 50 ℃, 40 ℃ or 30 ℃, but is not limited to the recited values, and other combinations not recited within the range are also applicable.

As a preferred technical solution of the present invention, the preparation method comprises:

firstly, arranging a gradient sulfurizing layer on a piece to be treated by adopting glow discharge, and then arranging a metal sulfurizing layer by adopting sputtering;

the glow discharge comprises first vacuumizing, ventilating, second vacuumizing and heating in sequence; the end point of the first vacuumizing is that the absolute vacuum degree is less than or equal to 10 Pa; the ventilation is to introduce a sulfurizing atmosphere; the sulfurizing atmosphere comprises hydrogen sulfide, hydrogen and inert gas; the end point of the second vacuumizing is 50-60Pa of absolute vacuum degree; the end point of the temperature rise is 160-180 ℃;

the absolute vacuum degree in the sputtering furnace is less than 0.0007 Pa; the working gas for sputtering comprises inert gas and/or nitrogen; the sputtering pressure is 1-7 Pa; the sputtering power is 90-320W; the sputtering time is 1-3 h; the temperature in the furnace during sputtering is less than 180 ℃.

In a third aspect, the present invention provides a transmission, wherein the surface of a component of the transmission is provided with the composite sulfurizing layer as described in the first aspect; the method specifically comprises the following steps: firstly, setting a gradient sulfurizing layer by adopting glow discharge, and then setting a metal sulfurizing layer by adopting sputtering;

preferably, the transmission parts comprise 1 or a combination of at least 2 of gears, shafts, spacers or washers.

In a fourth aspect, the invention provides a drive axle, wherein the surface of a part of the drive axle is provided with the composite sulfurizing layer as described in the first aspect; the method specifically comprises the following steps: firstly, setting a gradient sulfurizing layer by adopting glow discharge, and then setting a metal sulfurizing layer by adopting sputtering;

preferably, the transaxle part includes 1 or a combination of at least 2 of a reduction gear, a shaft, a washer, or a washer.

In the invention, the gear, shaft or gasket base material adopts carburizing steel, such as: 20. 20Cr or 20CrMnTiH, etc.

In the present invention, the inert gas may be 1 or a combination of at least 2 of helium, neon, argon, or the like.

Compared with the prior art, the invention at least has the following beneficial effects:

(1) the surface performance of the transmission part is improved by the specific selection of the molybdenum sulfurizing layer in the composite sulfurizing layer and the cooperation of the molybdenum sulfurizing layer and the gradient sulfurizing layer through the synergistic enhancement effect of the molybdenum sulfurizing layer and the gradient sulfurizing layer. The friction coefficient of the surface of a transmission part is obviously reduced, and the friction reducing performance is improved, so that the transmission has good wear resistance, gluing resistance and micro-pitting corrosion resistance, and the service life of the transmission is prolonged.

(2) In the invention, the performance of the transmission containing the composite sulfurizing layer is obviously improved, the friction coefficient is less than or equal to 0.08, the wear patch area (the test force is 30N, the rotating speed is 800r/min, the time is 2200s, the lubricating condition is 32# engine oil and one drop) is less than or equal to 2.5mm²And the dry grinding time (the test force is 30N, the rotating speed is 800r/min, and the composite seepage layer is abraded) is more than or equal to 4.3 h.

Detailed Description

To better illustrate the invention and to facilitate the understanding of the technical solutions thereof, typical but non-limiting examples of the invention are as follows:

example 1

The embodiment provides a composite sulfurizing layer, which comprises a gradient sulfurizing layer and a metal sulfurizing layer, wherein the gradient sulfurizing layer and the metal sulfurizing layer are sequentially arranged on a substrate;

the gradient sulfurizing layer comprises the following components in percentage by mass: 20% of oxygen, 8% of sulfur and the balance of iron; the gradient sulfurizing layer consists of ferrous sulfide, ferric sulfide, ferroferric oxide and ferric oxide;

the mass percentage of sulfur in the gradient sulfurizing layer is gradually reduced, and the surface of the gradient sulfurizing layer facing to the surface of the substrate is taken as a reference; the composite sulfurizing layer contains micropores less than or equal to 20 nm;

the metal sulfurizing layer comprises the following components in percentage by mass: 1% of metal element (molybdenum), 5% of sulfur and the balance of iron; the metal sulfurizing layer is a molybdenum sulfide layer;

the thickness of the gradient sulfurizing layer is 100 mu m; the thickness of the metal sulfurizing layer is 2 mu m;

the preparation method comprises the following steps:

the glow discharge comprises first vacuumizing, ventilating, second vacuumizing and heating in sequence; the end point of the first vacuumizing is that the absolute vacuum degree is 10 Pa; the ventilation is to introduce a sulfurizing atmosphere; the sulfurizing atmosphere is hydrogen sulfide, hydrogen and inert gas (argon); the end point of the second vacuumizing is that the absolute vacuum degree is 55 Pa; the end point of the temperature rise is 170 ℃;

the absolute vacuum degree in the sputtering furnace is 0.0005 Pa; the sputtering working gas is argon; the sputtering pressure is 4 Pa; the sputtering power is 210W; the sputtering time is 2 h; the temperature in the furnace during sputtering was 150 ℃.

Example 2

the gradient sulfurizing layer comprises the following components in percentage by mass: 1% of oxygen, 15% of sulfur and the balance of iron; the gradient sulfurizing layer consists of ferrous sulfide, ferric sulfide, ferroferric oxide and ferric oxide;

the mass percentage of sulfur in the gradient sulfurizing layer is gradually reduced, and the surface of the gradient sulfurizing layer facing to the surface of the substrate is taken as a reference; the composite sulfurizing layer contains 5-15nm micropores;

the metal sulfurizing layer comprises the following components in percentage by mass: 0.1% of metal element (tungsten), 9% of sulfur and the balance of iron; the metal sulfurizing layer is a tungsten sulfide layer;

the thickness of the gradient sulfurizing layer is 1 μm; the thickness of the metal sulfurizing layer is 5 mu m;

the preparation method comprises the following steps:

the glow discharge comprises first vacuumizing, ventilating, second vacuumizing and heating in sequence; the end point of the first vacuumizing is that the absolute vacuum degree is 1 Pa; the ventilation is to introduce a sulfurizing atmosphere; the sulfurizing atmosphere comprises hydrogen sulfide, hydrogen and inert gas (helium); the end point of the second vacuumizing is the absolute vacuum degree of 50 Pa; the end point of the temperature rise is 160 ℃;

the absolute vacuum degree in the sputtering furnace is 0.0001 Pa; the sputtering working gas is nitrogen; the pressure of the sputtering is 1 Pa; the power of the sputtering is 320W; the sputtering time is 3 h; the temperature in the furnace during sputtering was 80 ℃.

Example 3

the gradient sulfurizing layer comprises the following components in percentage by mass: 35% of oxygen, 0.1% of sulfur and the balance of iron; the gradient sulfurizing layer consists of ferrous sulfide, ferric sulfide, ferroferric oxide and ferric oxide;

the mass percentage of sulfur in the gradient sulfurizing layer is gradually reduced, and the surface of the gradient sulfurizing layer facing to the surface of the substrate is taken as a reference; the composite sulfurizing layer contains 1-20nm micropores;

the metal sulfurizing layer comprises the following components in percentage by mass: 2% of metal element (silver), 0.1% of sulfur and the balance of iron; the metal sulfurizing layer is a silver sulfide layer;

the thickness of the gradient sulfurizing layer is 200 μm; the thickness of the metal sulfurizing layer is 1 mu m;

the preparation method comprises the following steps:

the glow discharge comprises first vacuumizing, ventilating, second vacuumizing and heating in sequence; the end point of the first vacuumizing is that the absolute vacuum degree is 5 Pa; the ventilation is to introduce a sulfurizing atmosphere; the sulfurizing atmosphere comprises hydrogen sulfide, hydrogen and inert gas (helium); the end point of the second vacuumizing is the absolute vacuum degree of 60 Pa; the end point of the temperature rise is 180 ℃;

the absolute vacuum degree in the sputtering furnace is 0.0003 Pa; the sputtering working gas is nitrogen; the sputtering pressure is 7 Pa; the sputtering power is 90W; the sputtering time is 1 h; the temperature in the furnace during sputtering is 100 ℃.

Application example 1

The application example provides a transmission, wherein the surface of a part of the transmission is provided with the composite sulfurizing layer in the embodiment 1; the parts include gears, shafts, and washers. The performance results for the transmission are detailed in table 1.

Application example 2

The application example provides a transmission, wherein the surface of a part of the drive axle is provided with the composite sulfurizing layer in the embodiment 2; the parts include gears, shafts, and washers. The performance results for the transmission are detailed in table 1.

Application example 3

The application example provides a transmission, wherein the surface of a part of the transmission is provided with the composite sulfurizing layer in the embodiment 3; the parts include gears, shafts, and washers. The performance results for the transmission are detailed in table 1.

Comparative example 1

The difference from application example 1 is only that the order of arrangement of the gradient sulfurizing layer and the metal sulfurizing layer is changed, that is, the metal sulfurizing layer and the gradient sulfurizing layer are arranged in this order from the surface of the part. The performance results for the transmission are detailed in table 1.

Comparative example 2

The only difference from application example 1 was that the thickness of the metal-infiltrated layer was 100 μm, and the performance results of the transmission are detailed in table 1. In the using process, the coating falls off due to poor binding force, so that the performance of the metal sulfurizing layer cannot be fully exerted.

Comparative example 3

The only difference from application example 1 was that the metal-infiltrated layer was replaced with a boron sulfide layer and the performance results for the transmission are detailed in table 1.

TABLE 1

	Coefficient of friction	2200s abrasion area/mm²	Dry milling time/h
				Application example 1	0.01-0.05	1.5	4.5
Application example 2	0.02-0.08	2.5	5
				Application example 3	0.008-0.02	1.5	4.3
Comparative example 1	0.1-0.2	3	2
				Comparative example 2	0.07-0.09	2.3	1.5
Comparative example 3	0.09-0.13	2.7	2.3

In the application examples and the comparative examples, the friction coefficient, the antifriction property and the wear resistance are obtained by testing on a friction wear testing machine, and the specific detection process can be carried out by referring to GB/T12444-2006. Specifically, the experimental force is 30N, the rotating speed is 800r/min, and the lubricating condition is as follows: 32# Engine oil, one drop (0.05 mL).

From the results of the above examples and comparative examples, it can be seen that the composite sulfurized layer provided by the present invention can reduce the friction coefficient of transmission parts, provide good solid lubrication performance under the condition of insufficient supply of lubricating oil, and reduce the friction temperature; the oxide provides high wear resistance and bearing capacity, ensuring wear resistance between parts.

The applicant declares that the present invention illustrates the detailed structural features of the present invention through the above embodiments, but the present invention is not limited to the above detailed structural features, that is, it does not mean that the present invention must be implemented depending on the above detailed structural features. It should be understood by those skilled in the art that any modifications of the present invention, equivalent substitutions of selected components of the present invention, additions of auxiliary components, selection of specific modes, etc., are within the scope and disclosure of the present invention.

The preferred embodiments of the present invention have been described in detail, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.

It should be noted that the various technical features described in the above embodiments can be combined in any suitable manner without contradiction, and the invention is not described in any way for the possible combinations in order to avoid unnecessary repetition.

In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.

Claims

1. The composite sulfurizing layer is characterized by comprising a gradient sulfurizing layer and a metal sulfurizing layer which are sequentially arranged on a substrate;

the mass percentage of sulfur in the gradient sulfurizing layer is gradually reduced, and the surface of the gradient sulfurizing layer facing to the surface of the substrate is taken as a reference;

2. The composite sulfidizing layer of claim 1, wherein the gradient sulfidizing layer is composed of ferrous sulfide, ferric sulfide, ferroferric oxide, and ferric oxide;

preferably, the metal element comprises 1 or a combination of at least 2 of molybdenum, tungsten, copper, silver, zinc, or manganese;

preferably, the metal-sulfidizing layer comprises a metal sulfide;

preferably, the metal sulfide comprises molybdenum sulfide.

3. The composite sulfurized layer of claim 1 or 2, wherein the composite sulfurized layer contains micropores of 20nm or less.

4. A method of producing a composite sulphurized layer according to any one of claims 1 to 3, characterized in that it comprises:

5. The method of preparing a composite sulfurized layer as claimed in claim 4, wherein the glow discharge includes a first evacuation, a ventilation, a second evacuation and a temperature rise sequentially.

6. The method for preparing a composite sulfurized layer as claimed in claim 5, wherein the end point of the first evacuation is less than or equal to 10 Pa;

preferably, the aeration is the introduction of a sulfurizing atmosphere;

preferably, the sulfurizing atmosphere comprises hydrogen sulfide, hydrogen and an inert gas;

preferably, the end point of the second vacuumizing is the absolute vacuum degree of 50-60 Pa;

preferably, the end point of the temperature rise is 160-.

7. The method for producing a composite sulfurized layer as claimed in any one of claims 4 to 6, wherein the degree of vacuum in the furnace during sputtering is < 0.0007 Pa;

preferably, the working gas for sputtering comprises an inert gas and/or nitrogen;

preferably, the pressure of the sputtering is 1-7 Pa;

preferably, the power of the sputtering is 90-320W;

preferably, the sputtering time is 1-3 h;

preferably, the temperature in the furnace during sputtering is < 180 ℃.

8. The method of producing a composite sulfurized layer as claimed in any one of claims 4 to 7, wherein the production method includes:

9. A transmission characterized in that a surface of a component of the transmission is provided with the composite sulfurized layer as defined in any one of claims 1 to 3; the method specifically comprises the following steps: firstly, setting a gradient sulfurizing layer by adopting glow discharge, and then setting a metal sulfurizing layer by adopting sputtering;

10. A drive axle, characterized in that the surface of the component of the drive axle is provided with a composite sulphurized layer according to any one of claims 1-3; the method specifically comprises the following steps: firstly, setting a gradient sulfurizing layer by adopting glow discharge, and then setting a metal sulfurizing layer by adopting sputtering;