CN112746247A

CN112746247A - Self-lubricating gear and preparation method thereof

Info

Publication number: CN112746247A
Application number: CN202011477479.XA
Authority: CN
Inventors: 邢佑强; 吴泽; 刘磊; 李燕凡
Original assignee: Southeast University
Current assignee: Southeast University
Priority date: 2020-12-15
Filing date: 2020-12-15
Publication date: 2021-05-04

Abstract

The invention discloses a self-lubricating gear and a preparation method thereof. The self-lubricating gear comprises a bearing matrix, a microtexture and a composite coating, and the microtexture and the composite coating are coated on the surface of the bearing matrix; The composite coating includes a first coating layer and a second coating layer, and the first coating layer and the second coating layer are alternately stacked; the first coating layer is a ZrZnMoN layer, and the second coating layer is a TiAgVC layer. The microtexture is prepared by laser processing, and the coating is prepared by the method of multi-arc ion plating + intermediate frequency magnetron sputtering co-deposition. When the working temperature of the gear is high, the ZrZnMoN coating and TiAgVC coating will react with oxygen in the air to generate ZnMoO ₄ and Ag ₃ VO ₄ compounds with high temperature lubrication, which can play a lubricating role. The micro-texture is combined with the self-lubricating coating, which can effectively reduce the friction and wear of the tooth surface and improve the life of the gear.

Description

Self-lubricating gear and preparation method thereof

Technical Field

The invention belongs to the technical field of gear manufacturing, and particularly relates to a self-lubricating gear and a preparation method thereof.

Background

In the process of gear transmission, large friction and abrasion exist between tooth surfaces to generate high heat, and if the heat generation of the gear in unit time is far greater than the heat dissipation, the temperature of the gear is higher and higher, so that the gear is easy to lose efficacy due to overhigh temperature. Therefore, the lubrication can reduce the friction wear of the tooth surface, and has important significance for prolonging the service life of the gear. The self-lubricating gear does not need lubricating oil and a complex lubricating system thereof, can form a lubricating film on the working surface, realizes the lubricating effect in the working process of the gear, and thus reduces the frictional wear and heat generation.

Chinese patent "application number: 201711395397.9 discloses a self-lubricating gear with micro-texture, which is characterized in that the surface of the gear is processed with the micro-texture and filled with a lubricating medium, and the micro-texture is softened at high friction temperature to form a lubricating film, thereby realizing the continuous self-lubricating effect in the friction area of the gear. Chinese patent "application number: 201710086850.1 discloses a honeycomb polygonal self-lubricating gear, which is characterized in that honeycomb grooves and strip-shaped grooves are processed on the surface of the gear based on bionics, and the self-lubricating effect of gear engagement is realized by filling a solid lubricant in the bionic grooves. Chinese patent "application number: 201810145366.6 discloses a multi-material composite self-lubricating gear, which is prepared by a 3D printing technology on the surface of a gear substrate to realize the self-lubricating function of the gear.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the invention provides a self-lubricating gear and a preparation method thereof, wherein the gear can generate a lubricating film on the surface in a high-temperature environment, and the self-lubricating effect of the gear in the working process is realized, so that the frictional wear of the tooth surface is reduced, and the service life of the gear is prolonged.

In order to solve the technical problem, in one aspect, an embodiment of the present invention provides a self-lubricating gear, including a bearing substrate, a micro-texture and a composite coating, where the micro-texture and the composite coating are coated on a surface of the bearing substrate; the composite coating comprises a first coating and a second coating, and the first coating and the second coating are alternately superposed; the first coating is a ZrZnMoN layer, and the second coating is a TiAgVC layer.

Preferably, the composite coating at least comprises 5 ZrZnMoN layers and 5 TiAgVC layers, and the single-layer thickness of the first coating and the single-layer thickness of the second coating are both less than or equal to 200 nm.

Preferably, in the first coating, the atomic percent of Zr element is 30-50%, the atomic percent of Zn element is 10-20%, the atomic percent of Mo element is 10-20%, the atomic percent of N element is 20-35%, and the sum of the atomic percent of Zr, Zn, Mo and N element is 100%.

Preferably, in the second coating, the atomic percent of Ti element is 20-30%, the atomic percent of Ag element is 15-25%, the atomic percent of V element is 10-20%, the atomic percent of C element is 30-40%, and the sum of the atomic percent of Ti, Ag, V and C element is 100%.

Preferably, the gear base material is carbon steel or cast iron.

On the other hand, the embodiment of the invention provides a preparation method for preparing a self-lubricating gear, which comprises the following steps:

step 1, preparing a micro-texture by laser processing;

and 2, preparing the composite coating by adopting a method of multi-arc ion plating and medium-frequency magnetron sputtering codeposition.

Preferably, the micro texture is prepared by laser processing, and the specific preparation method comprises the following steps:

step 1, pretreatment: grinding and polishing the gear matrix, and sequentially putting the gear matrix into alcohol and acetone for ultrasonic cleaning for 20-30min respectively to remove oil stain pollutants on the surface;

step 2, processing the microtexture: and (3) processing a micro-texture on the surface of the gear matrix by adopting nanosecond laser, wherein the width of the micro-texture is 10-100 mu m, and the depth of the micro-texture is 10-200 mu m.

Preferably, the composite coating is prepared by adopting a method of multi-arc ion plating and medium-frequency magnetron sputtering codeposition, and the specific preparation method comprises the following steps:

step 1, placing the textured gear into alcohol for ultrasonic cleaning for 20-30min, fully drying the gear by adopting a vacuum drying oven, and quickly placing the gear into a vacuum chamber of a film coating machine, wherein the background vacuum of the vacuum chamber is 7.0 multiplied by 10^-3-8.0×10^-3Pa, heating to 150 ℃ and 200 ℃, and keeping the temperature for 30-40 min;

step 2, introducing Ar gas with the pressure of 0.5-3.0Pa, starting a bias voltage power supply with the voltage of 600-1000V and the duty ratio of 0.25-0.3, and performing glow discharge cleaning for 20-30 min; reducing the bias voltage to 250-600V, starting ion source ion cleaning for 20-30min, starting the arc source Zr target, wherein the bias voltage is 300-600V, the target current is 40-60A, and the ion bombards the Zr target for 0.5-2.0 min;

step 3, adjusting the working air pressure to be 0.5-3.5Pa, the bias voltage to be 150-300V, adjusting the Zr target current to be 80-120A, starting the ZnMoN target, adjusting the target current to be 60-100A, and depositing the first coating for 2-15 min;

step 4, closing the Zr target and the ZnMoN target, adjusting the working air pressure to be 0.6-2.0Pa, adjusting the bias voltage to be 200-300V, starting the electric arc power supply of the Ti target, the Ag target and the VC target, wherein the current of the Ti target is 100-120A, the current of the Ag target is 60-80A, the current of the VC target is 80-120A, and depositing a second coating for 2-15 min;

step 5, repeating the step 3 and the step 4, and alternately depositing the first coating and the second coating to obtain a laminated coating, wherein the total thickness of the composite coating is 2-100 mu m;

and 6, closing all the targets, the bias power supply and the gas source, preserving the heat for 30-60min, and finishing the coating.

Has the advantages that: 1. the gear has good self-lubricating effect under the high-temperature working condition, and ZrZnMoN and TiAgVC react with oxygen in the air at higher temperature to generate ZnMoO with high-temperature lubricating effect₄And Ag₃VO₄The compound can play a good lubricating role under the high-temperature condition; 2. the micro-texture on the surface of the gear can improve the bonding strength of a matrix and a coating, can collect abrasive dust and a high-temperature lubricating phase, and plays roles in reducing abrasive wear and providing secondary lubrication, so that the service life of the gear is prolonged; 3. the gear surface coating of the invention is of a nano laminated structure, the internal stress is small, and the coatingThe bonding strength is high; 4. the gear is a self-lubricating gear, does not need lubricating oil or a complex lubricating system thereof, and has simple structure and convenient use.

Drawings

Fig. 1 is a schematic structural view of a self-lubricating gear of the present invention.

In the figure: 1 gear substrate, 2 microtexture, 3 first coating and 4 second coating.

Detailed Description

The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.

As shown in fig. 1, the embodiment adopted by the present invention is as follows:

example 1: a self-lubricating gear is characterized in that a gear base material is 45 carbon steel, and the surface of the base material is provided with a self-lubricating laminated coating with a micro texture and ZrZnMoN + TiAgVC alternately distributed. The laminated coating contains 5 ZrZnMoN layers and 5 TiAgVC layers, and the thickness of each ZrZnMoN layer and each TiAgVC layer is 200 nm.

According to the self-lubricating gear, the atomic percent of Zr element in the ZrZnMoN coating is 50%, the atomic percent of Zn element is 10%, the atomic percent of Mo element is 20%, the atomic percent of N element is 20%, and the sum of the atomic percent of Zr, Zn, Mo and N element is 100%; in the TiAgVC coating, the atomic percent of Ti element is 30%, the atomic percent of Ag element is 20%, the atomic percent of V element is 10%, the atomic percent of C element is 40%, and the sum of the atomic percent of Ti, Ag, V and C element is 100%.

The preparation method of the self-lubricating gear comprises the following steps:

step 1, preparing a micro-texture by laser processing;

Further, the method for preparing the microtexture by laser processing comprises the following steps:

step 1, pretreatment: grinding and polishing the gear matrix, and sequentially putting the gear matrix into alcohol and acetone for ultrasonic cleaning for 20min respectively to remove oil stain pollutants on the surface;

step 2, processing the microtexture: processing a micro-texture on the surface of a gear matrix by nanosecond laser, wherein the width of the micro-texture is 20 micrometers, and the depth of the micro-texture is 20 micrometers;

further, the composite coating is prepared by adopting a method of multi-arc ion plating and medium-frequency magnetron sputtering codeposition, and the specific preparation method comprises the following steps:

step 1, placing the textured gear into alcohol for ultrasonic cleaning for 20min, fully drying the gear by adopting a vacuum drying oven, and quickly placing the gear into a vacuum chamber of a film coating machine, wherein the background vacuum of the vacuum chamber is 7.0 multiplied by 10^-3Pa, heating to 150 ℃, and keeping the temperature for 30 min;

step 2, introducing Ar gas, starting a bias voltage power supply with the voltage of 600V and the duty ratio of 0.3 under the pressure of 1.0Pa, and performing glow discharge cleaning for 20 min; reducing the bias voltage to 250V, starting ion source ion cleaning for 20min, starting an arc source Zr target, wherein the bias voltage is 300V, the target current is 40A, and ion bombardment Zr is carried out for 1.0 min;

step 3, adjusting the working pressure to be 1.5Pa, the bias voltage to be 150V, adjusting the Zr target current to be 120A, starting the ZnMoN target, adjusting the target current to be 80A, and depositing the ZrZnMoN coating for 12 min;

step 4, closing the Zr target and the ZnMoN target, adjusting the working air pressure to be 2.0Pa, adjusting the bias voltage to be 200V, starting the Ti target, the Ag target and the VC target arc power supply, setting the Ti target current to be 120A, the Ag target current to be 60A and the VC target current to be 90A, and depositing the TiAgVC coating for 12 min;

step 5, repeating the steps 3 and 4, and alternately depositing a ZrZnMoN + TiAgVC laminated coating to enable the total thickness of the coating to be 2 microns;

and 6, closing all the targets, the bias power supply and the gas source, preserving the heat for 60min, and finishing the coating.

Example 2: a self-lubricating gear is characterized in that a gear substrate is made of HT200 cast iron, and the surface of the gear substrate is provided with a laminated coating with a micro texture and ZrZnMoN + TiAgVC alternately distributed. The laminated coating comprises 50 ZrZnMoN layers and 50 TiAgVC layers, and the thickness of each ZrZnMoN layer and each TiAgVC layer is 100 nm.

According to the self-lubricating gear, the atomic percent of Zr element in the ZrZnMoN coating is 35%, the atomic percent of Zn element is 20%, the atomic percent of Mo element is 15%, the atomic percent of N element is 30%, and the sum of the atomic percent of the Zr element, the Zn element, the Mo element and the N element is 100%; in the TiAgVC coating, the atomic percent of Ti element is 25%, the atomic percent of Ag element is 25%, the atomic percent of V element is 20%, the atomic percent of C element is 30%, and the sum of the atomic percent of Ti, Ag, V and C element is 100%.

step 1, preparing a micro-texture by laser processing;

step 1, pretreatment: grinding and polishing the gear matrix, and sequentially putting the gear matrix into alcohol and acetone for ultrasonic cleaning for 30min to remove oil stain pollutants on the surface;

step 2, processing the microtexture: processing a micro-texture on the surface of a gear matrix by nanosecond laser, wherein the width of the micro-texture is 80 mu m, and the depth of the micro-texture is 100 mu m;

step 1, placing the textured gear into alcohol for ultrasonic cleaning for 30min, fully drying the gear by adopting a vacuum drying oven, and quickly placing the gear into a vacuum chamber of a film coating machine, wherein the background vacuum of the vacuum chamber is 8.0 multiplied by 10^-3Pa, heating to 200 ℃, and keeping the temperature for 40 min;

step 2, introducing Ar gas, starting a bias voltage power supply with the voltage of 900V and the duty ratio of 0.25 under the pressure of 3.0Pa, and carrying out glow discharge cleaning for 30 min; reducing the bias voltage to 500V, starting ion source ion cleaning for 25min, starting an arc source Zr target, wherein the bias voltage is 500V, the target current is 50A, and the ion bombards the Zr target for 2.0 min;

step 3, adjusting the working pressure to be 3.5Pa, the bias voltage to be 250V, adjusting the Zr target current to be 90A, starting the ZnMoN target, adjusting the target current to be 100A, and depositing the ZrZnMoN coating for 3 min;

step 4, closing the Zr target and the ZnMoN target, adjusting the working air pressure to be 2.0Pa, adjusting the bias voltage to be 300V, starting the Ti target, the Ag target and the VC target arc power supply, setting the current of the Ti target to be 100A, the current of the Ag target to be 80A and the current of the VC target to be 100A, and depositing the TiAgVC coating for 3 min;

step 5, repeating the steps 3 and 4, and alternately depositing a ZrZnMoN + TiAgVC laminated coating to enable the total thickness of the coating to be 10 microns;

and 6, closing all the targets, the bias power supply and the gas source, preserving the heat for 40min, and finishing the coating.

Example 3: a self-lubricating gear is characterized in that a gear substrate is made of HT200 cast iron, and the surface of the gear substrate is provided with a laminated coating with a micro texture and ZrZnMoN + TiAgVC alternately distributed. The laminated coating comprises 20 ZrZnMoN layers and 20 TiAgVC layers, and the thickness of each ZrZnMoN layer and each TiAgVC layer is 80 nm.

According to the self-lubricating gear, the atomic percent of Zr element in the ZrZnMoN coating is 30%, the atomic percent of Zn element is 15%, the atomic percent of Mo element is 20%, the atomic percent of N element is 35%, and the sum of the atomic percent of Zr, Zn, Mo and N element is 100%; in the TiAgVC coating, the atomic percent of Ti element is 30%, the atomic percent of Ag element is 15%, the atomic percent of V element is 18%, the atomic percent of C element is 37%, and the sum of the atomic percent of Ti, Ag, V and C element is 100%.

step 1, preparing a micro-texture by laser processing;

step 1, pretreatment: grinding and polishing the gear matrix, and sequentially putting the gear matrix into alcohol and acetone for ultrasonic cleaning for 25min to remove oil stain pollutants on the surface;

step 2, processing the microtexture: processing a micro-texture on the surface of a gear matrix by nanosecond laser, wherein the width of the micro-texture is 10 mu m, and the depth of the micro-texture is 10 mu m;

step 1, placing the textured gear into alcohol for ultrasonic cleaning for 25min, fully drying the gear by adopting a vacuum drying oven, and quickly placing the gear into a vacuum chamber of a film coating machine, wherein the background vacuum of the vacuum chamber is 7.5 multiplied by 10^-3Pa, heating to 180 ℃, and keeping the temperature for 35 min;

step 2, introducing Ar gas, starting a bias voltage power supply with the voltage of 1000V and the duty ratio of 0.27 under the pressure of 0.5Pa, and carrying out glow discharge cleaning for 25 min; reducing the bias voltage to 600V, starting ion source ion cleaning for 30min, starting an arc source Zr target, wherein the bias voltage is 600V, the target current is 60A, and the ion bombardment Zr target is subjected to 0.5 min;

step 3, adjusting the working pressure to be 0.5Pa, the bias voltage to be 300V, adjusting the Zr target current to be 80A, starting the ZnMoN target, adjusting the target current to be 60A, and depositing the ZrZnMoN coating for 2 min;

step 4, closing the Zr target and the ZnMoN target, adjusting the working air pressure to be 0.6Pa, adjusting the bias voltage to be 250V, starting the Ti target, the Ag target and the VC target arc power supply, setting the Ti target current to be 110A, the Ag target current to be 70A and the VC target current to be 80A, and depositing the TiAgVC coating for 2 min;

step 5, repeating the steps 3 and 4, and alternately depositing a ZrZnMoN + TiAgVC laminated coating to enable the total thickness of the coating to be 100 mu m;

and 6, closing all the targets, the bias power supply and the gas source, preserving the heat for 30min, and finishing the coating.

Example 4: a self-lubricating gear is characterized in that a gear substrate is made of HT200 cast iron, and the surface of the gear substrate is provided with a laminated coating with a micro texture and ZrZnMoN + TiAgVC alternately distributed. The laminated coating contains 40 ZrZnMoN layers and 40 TiAgVC layers, and the thickness of each ZrZnMoN layer and each TiAgVC layer is 50 nm.

According to the self-lubricating gear, the atomic percent of Zr element in the ZrZnMoN coating is 35%, the atomic percent of Zn element is 20%, the atomic percent of Mo element is 10%, the atomic percent of N element is 35%, and the sum of the atomic percent of Zr, Zn, Mo and N element is 100%; in the TiAgVC coating, the atomic percent of Ti element is 20%, the atomic percent of Ag element is 20%, the atomic percent of V element is 20%, the atomic percent of C element is 40%, and the sum of the atomic percent of Ti, Ag, V and C element is 100%.

step 1, preparing a micro-texture by laser processing;

step 2, processing the microtexture: processing a micro-texture on the surface of a gear matrix by nanosecond laser, wherein the width of the micro-texture is 100 micrometers, and the depth of the micro-texture is 200 micrometers;

step 3, adjusting the working pressure to be 3.5Pa, the bias voltage to be 250V, adjusting the Zr target current to be 90A, starting the ZnMoN target, adjusting the target current to be 100A, and depositing the ZrZnMoN coating for 15 min;

step 4, closing the Zr target and the ZnMoN target, adjusting the working air pressure to be 1.0Pa, adjusting the bias voltage to be 300V, starting the Ti target, the Ag target and the VC target arc power supply, setting the Ti target current to be 100A, the Ag target current to be 80A and the VC target current to be 120A, and depositing the TiAgVC coating for 15 min;

step 5, repeating the steps 3 and 4, and alternately depositing a ZrZnMoN + TiAgVC laminated coating to enable the total thickness of the coating to be 50 microns;

The embodiments of the present invention are merely preferred embodiments of the present invention, and are not intended to limit the scope of the present invention. That is, all equivalent changes and modifications made according to the content of the claims of the present invention should be regarded as the technical scope of the present invention.

Claims

1. A self-lubricating gear, characterized in that it comprises a bearing matrix (1), a microtexture (2) and a composite coating, wherein the microtexture (2) and the composite coating are coated on the bearing matrix ( 1) surface; the composite coating comprises a first coating (3) and a second coating (4), and the first coating (3) and the second coating (4) are alternately superimposed; the first coating (3) and the second coating (4) are alternately stacked; The first coating (3) is a ZrZnMoN layer, and the second coating (4) is a TiAgVC layer.

2. The self-lubricating gear according to claim 1, wherein the composite coating contains at least 5 ZrZnMoN layers and 5 TiAgVC layers, the first coating (3) and the second coating (4) The thickness of the single layer is less than or equal to 200nm.

3. The self-lubricating gear according to claim 1, characterized in that, in the first coating (3), the atomic percentage of Zr element is 30-50%, the atomic percentage of Zn element is 10-20%, and the atomic percentage of Mo element is 30-50%. The atomic percentage is 10-20%, the atomic percentage of the N element is 20-35%, and the sum of the atomic percentage of the Zr, Zn, Mo, and N elements is 100%.

4. The self-lubricating gear according to claim 1, characterized in that, in the second coating (4), the atomic percentage of Ti element is 20-30%, the atomic percentage of Ag element is 15-25%, and the atomic percentage of V element is 20-30%. The atomic percentage is 10-20%, the atomic percentage of C element is 30-40%, and the sum of the atomic percentage of the Ti, Ag, V, and C elements is 100%.

5. The self-lubricating gear according to claim 1, characterized in that, the material of the gear base (1) is carbon steel or cast iron.

6. a preparation method for preparing the self-lubricating gear described in any one of claims 1-5, is characterized in that, comprising:

Step 1, using laser processing to prepare microtexture (2);

Step 2, the composite coating is prepared by the method of multi-arc ion plating + intermediate frequency magnetron sputtering co-deposition.

7. The preparation method of the self-lubricating gear according to claim 6, wherein the preparation of the microtexture (2) by laser processing, the specific preparation method comprises the following steps:

Step 1. Pretreatment: Grind and polish the gear base (1), and then put it into alcohol and acetone for ultrasonic cleaning for 20-30min each to remove oily contaminants on the surface;

Step 2, processing the microtexture (2): using a nanosecond laser to process the microtexture (2) on the surface of the gear substrate (1), the width of the microtexture (2) is 10-100 μm, and the depth of the microtexture (2) 10-200μm.

8. the preparation method of self-lubricating gear according to claim 6, is characterized in that, described adopts the method of multi-arc ion plating+intermediate frequency magnetron sputtering co-deposition to prepare composite coating, and concrete preparation method comprises the following steps:

Step 1. Put the textured gear into alcohol for ultrasonic cleaning for 20-30min, fully dry it in a vacuum drying oven, and quickly put it into the vacuum chamber of the coating machine. The background vacuum of the vacuum chamber is 7.0×10 ^-3 -8.0×10 ^-3 Pa, heated to 150-200℃, holding time 30-40min;

Step 2. Enter Ar gas, the pressure is 0.5-3.0Pa, turn on the bias power supply, the voltage is 600-1000V, the duty cycle is 0.25-0.3, and the glow discharge cleaning is 20-30min; the bias voltage is reduced to 250-600V , turn on the ion source for ion cleaning for 20-30min, turn on the arc source Zr target, the bias voltage is 300-600V, the target current is 40-60A, and the ion bombards the Zr target for 0.5-2.0min;

Step 3. Adjust the working pressure to 0.5-3.5Pa, the bias voltage to 150-300V, adjust the Zr target current to 80-120A, turn on the ZnMoN target, adjust the target current to 60-100A, and deposit the first coating (3)2- 15min;

Step 4. Turn off the Zr target and the ZnMoN target, adjust the working pressure to 0.6-2.0Pa, the bias voltage to 200-300V, turn on the arc power of the Ti target, the Ag target and the VC target, the current of the Ti target is 100-120A, and the current of the Ag target is 60-80A, the VC target current is 80-120A, and the second coating (4) is deposited for 2-15min;

Step 5, repeating the above steps 3 and 4, alternately depositing the first coating (3) and the second coating (4) to obtain a laminated coating, so that the total thickness of the composite coating is 2-100 μm;

Step 6. Turn off all target materials, bias power supply and gas source, keep the temperature for 30-60min, and finish the coating.