KR100359496B1 - DEVEIOPMENT METHOD OF AI-Sn COATING FILM METAL BEARINGS FOR DIESEL ENGINES BY RF MAGNETRON SPUTTERING PROCESS - Google Patents

Abstract

The present invention relates to a manufacturing method of a coating film metal bearing for an aluminum (AI) -tin (Sn) -based diesel engine by a magnetron sputtering process,

Magnetron sputtering, one of physical vapor deposition (PVD), is used to form a vacuum in order to improve the linear motion of atoms, molecules, and ions in the vacuum vessel (1) of the apparatus. 2) sputtered aluminum (AI) and tin (Sn) metal targets to which positive argon ( Ar ⁺ ) ions are to be deposited by supplying inert argon gas, and the atoms protruding from the targets are radio frequency. (RF) Atoms, molecules, and ions collide by the supply of power,

At this time, the generated electrons are spirally moved by the magnetic field and the average free stroke (the average distance traveled until one molecule moves under vacuum and collides with another) becomes long, causing inelastic collision with other molecules and ionizing with cations. At the same time, atoms and molecules in a vacuum vessel undergo continuous collisions, and atoms are excited or ionized to form a plasma,

At this time, a method of manufacturing an aluminum (AI) -tin (Sn) coating film metal bearing by depositing on the substrate in the state of atoms, molecules or ions of aluminum (AI) and tin (Sn) metal sputtered from the target. As

The base material for manufacturing the coating film bearing is a sintered kemet (2 mm thick) that can compensate for the lubricity even in the local damage of the coating film on a conventional rolled steel ss41 steel, and to improve the adhesion between the material and the coating film Primary cleaning by ultrasonic cleaning of the base material and secondary cleaning by ion bombardment in vacuum vessel.

After cleaning, the coating conditions of the coating film were supplied to a vacuum chamber with a constant argon gas pressure, and maintained at a constant vacuum, so that the aluminum and tin targets were 230w and 55w, respectively, while the argon gas pressure was maintained. The composition ratio of the film produced by applying RF voltage is 75% AI and 25% Sn alloy film, and the coating film is made by the magnetron sputtering method, which is a dry plating method, which was generated by the conventional wet method. There is no fear of discharge of waste liquid and harmful gas,

It is to provide a method of manufacturing a coating film metal bearing for diesel engines by a magnetron sputtering process that can improve pollution and lead resistance, wear resistance, lubricity, durability and corrosion resistance due to lead.

Description

Manufacturing method of coating film metal bearing for aluminum-tin-based diesel engine by magnetron sputtering process {DEVEIOPMENT METHOD OF AI-Sn COATING FILM METAL BEARINGS FOR DIESEL ENGINES BY RF MAGNETRON SPUTTERING PROCESS}

The present invention provides an aluminum-tin based coating film on the surface of a metal bearing for a diesel engine by magnetron sputtering to improve the wear resistance, lubricity, durability and corrosion resistance of the coating film, as well as the environment. The present invention relates to a method for producing a coating film metal bearing for an aluminum (AI) -tin (Sn) -based diesel engine by a magnetron sputtering process capable of eliminating contamination.

In general, the surface treatment method, which is the last step in the process of the metal bearing material, improves lubrication performance by reducing the friction coefficient, thereby giving excellent durability as well as economic efficiency.

However, wet plating, which is most commonly used as the surface treatment method of metal bearings, has reached a functional limit in improving tribology characteristics such as adhesion, friction, and abrasion, and problems such as pollution generation due to waste liquid treatment in the process. This situation exists.

In addition, the use of lead (Pb) metal as a metal bearing material with excellent lubrication is mainly occupied in white metal bearings, kelmet ternary plated film bearings, and the like.

However, since this lead (Pb) metal is harmful to the environment, the movement to restrict its use has been active since 2004. Therefore, the selection of alternative materials and the surface treatment of metal bearing materials using environmentally-friendly dry plating methods are urgently needed. Is required.

Meanwhile, metal bearings used in main bearings and connecting rod bearings are driven in more and more harsh environments due to the demand for high performance such as high load, high load, and high speed rotation of diesel engines.

Therefore, in the surface treatment, which is the finishing process of metal bearings, the selection of materials and the surface treatment process to improve adhesion, durability, lubrication, wear resistance and corrosion resistance are important parts.

In the case of surface treatment through wet plating currently applied to the manufacture of metal bearings, there was a problem about environmental pollution due to the use of lead (Pb) metal, which is a material used as a treatment process and a coating film.

In addition, due to the high speed, high load, high load, and high performance of the diesel engine, the main bearings and connecting rod bearings require tribology for high wear resistance, lubrication, and corrosion resistance. There was a problem that could not be revived.

The present invention uses a magnetron sputtering method, one of physical vapor deposition (PVD) to solve the above problems, to improve the linear motion of atoms, molecules and ions in the vacuum vessel (1) of the device To create a vacuum,

Inert argon gas is supplied from the argon gas cylinder (2) to sputter the aluminum (AI) and tin (Sn) metal targets to which positive argon ( Ar ⁺ ) ions are to be deposited, and the atoms protrude from the targets. Causes collision of atoms, molecules, and ions by the supply of radio frequency (RF) power,

At this time, the generated electrons are spirally moved by the magnetic field and the average free stroke (the average distance traveled until one molecule moves under vacuum and collides with another) becomes long, causing inelastic collision with other molecules and ionizing with cations. At the same time, atoms and molecules in a vacuum vessel undergo continuous collisions, and atoms are excited or ionized to form a plasma,

At this time, a method of manufacturing an aluminum (AI) -tin (Sn) coating film metal bearing by depositing on the substrate in the state of atoms, molecules or ions of aluminum (AI) and tin (Sn) metal sputtered from the target. As

The base material for the production of coating film bearings is a sintered kelmet having a thickness of 2 mm on a conventional rolled steel ss41 steel that can compensate for lubrication even in local damage of the coating film, and the base material for improving adhesion between the material and the coating film. The primary cleaning by ultrasonic cleaning and the secondary cleaning by ion bombardment are carried out in a vacuum vessel.

After cleaning, the coating conditions of the coating film were supplied to a vacuum chamber with a constant argon gas pressure and maintained at a constant vacuum, so that the aluminum (AI) and tin (Sn) targets were 230w and 55w, respectively, while the argon gas pressure was maintained. The composition ratio of the film produced by applying RF voltage is 75% AI 25Sn alloy film, and the coating film is made by the magnetron sputtering method, which is a dry plating method. There is no fear of the release,

It is to provide a method of manufacturing a coating film metal bearing for diesel engines by a magnetron sputtering process that can improve pollution and lead resistance, wear resistance, lubrication, durability and corrosion resistance due to lead.

1 is a device diagram of an example used in the present invention (schematic diagram of an RF Magnetron Sputtering device)

Figure 2 is a coating film forming process of the present invention

Figure 3 is a friction coefficient change of the aluminum (AI) -tin (Sn) -based coating film and the three-way plating film.

Explanation of symbols for the main parts of the drawings

1: vacuum container

2: Rotary Pump (R / P)

3: turbomolecular pump (TMP)

4: RF GENERATOR

5: Bias Voltage Supply (DC POWER SUPPLY)

6: aluminum target (AI target)

7: Tin target

8: specimen hanger

9: argon gas

10: nitrogen gas

11: gas flow regulator

12: flow controller

The bearing base material for forming aluminum (AI) -tin (Sn) -based coating on the surface is based on ss41 steel, which can primarily support high loads, and has a basic lubricity kelmet on it. Using a base material that can supplement the lubricity even in the local damage of the film by sintering to a degree: Producing a material with excellent lubricity, such as lead (Pb) in the form of aluminum (AI) -tin (Sn) -based alloy And: forming an aluminum (AI) -tin (Sn) -based coating film in a magnetron sputtering method using a plasma state while maintaining a constant vacuum degree to enable a film having good adhesion and lubricity to the film. The radio frequency (RF) required to form an alloy film of 75% aluminum (AI) and 25% tin (Sn) in the aluminum (AI) -tin (Sn) target while maintaining the degree of vacuum. Applying a circle at 230w and 55w, respectively: forming a coating film with an alloy film of 75% AI 25% Sn, and producing a coating film bearing to form a base material and aluminum (AI) -tin (Sn). It is characterized by improving adhesion with the membrane, abrasion resistance, lubrication and corrosion resistance.

(Example)

The present invention is described in detail as follows.

1 is an example of a magnetron sputtering apparatus for manufacturing an aluminum (AI) -tin (Sn) -based coating film metal bearing according to the present invention,

The vacuum in the vacuum container 1 forms a vacuum degree by a rotary pump 2 and a turbo monlecular pump 3, forms a plasma through the generator 4, and targets aluminum (AI). (6) and tin (Sn) (7) form a magnetic field by the magnetic poles of the north pole and the south pole to increase the number of collisions due to the spiral motion, thereby generating plasma by excitation of atoms and molecules and generated ions. Will activate more.

The sequential method of forming the aluminum (AI) -tin (Sn) based film is as shown in the flowchart of the manufacturing of the aluminum (AI) -tin (Sn) coated film bearing of FIG.

First, the base material is sintered 2 mm of kelmet on the base material (ss41) and then mirror-polished and ultrasonic cleaning and acetone for 20 minutes by skim milk are used to remove oils remaining on the surface of the specimen to improve adhesion between the membrane and the base material. After washing the base material with alcohol for 15 minutes, it is mounted on the specimen hanger (8) in the vacuum container.

A rotary pump and a turbomolecular pump are used to install the specimen in the vacuum vessel (1) and to remove the residual gas and water in the vacuum vessel to improve the straightness of the metal atoms protruding from the target inert argon gas and the target. by Jean cavity 2 X 10 ^-5 Torr (torr) in order to the cleaning of the adsorbent particles in the exhaust after the base metal surface supplied with argon gas of high purity through the gas regulator (11), (12) 1 X 10 -2 Torr While maintaining the vacuum degree of tor, the secondary material is subjected to secondary cleaning through ion-bomardment for 20 minutes by applying a bias voltage of -700V to the base material through the bias voltage supply 5.

In addition, after cleaning the contaminated surface layer on the surface of the target through the pre-sputter of aluminum (AI) and tin (Sn) targets, and again evacuating the vacuum container sufficiently, vacuum is supplied by argon gas. Is maintained at 5 x 10 ^-3 torr, and 230w and 55w are applied to the aluminum (AI) and tin (Sn) targets to form a plasma, and the AI in the plasma is formed. Ions of ⁺ and Sn ⁺ and aluminum (AI) and tin (Sn) in atomic and molecular form are formed on the base material as a coating film.

The change in the friction coefficient of the aluminum (AI) -tin (Sn) -based coating films formed as described above is shown in FIG. 3 compared to the ternary plating film used as the practical metal bearing.

According to the composition ratio of aluminum (AI) and tin (Sn), it can be seen that the change of the friction coefficient shows a low and stable friction behavior at 75% AI 25% Sn. On the other hand, in the case of three-way plating, the initial friction coefficient is low, but the instantaneous friction coefficient is increased, indicating that the friction characteristics are poor in terms of lubrication characteristics and durability.

Thus, the present invention forms an aluminum (AI) -tin (Sn) -based coating film by the magnetron sputtering method, lubricating without using lead (Pb) metal harmful to the environment in the case of metal bearings for diesel engines. In addition to the improved properties, it is effective in solving the problems that hinder the environment through the dry plating process that is excellent in durability, wear resistance and environmentally friendly.

Claims (1)

In the development method of the coating film metal bearing for aluminum (AI) -tin (Sn) -based diesel engine by the magnetron sputtering method of dry plating method, First, the base material is formed by sintering about 2mm of kelmet on the ss41 steel which can support high load, so that the lubricity can be compensated for local damage of the coating film on the material. In order to improve the adhesion between the base material and the coating film, the base material is first washed by ultrasonic cleaning, and the base material is mounted in a vacuum container in a predetermined space, and then inert argon is introduced. In order to provide good adhesion and lubricity and to enable the production of a coating film, a constant vacuum pressure is applied to the vacuum container, and secondary cleaning is performed through an ion bomb bament to clean the contaminated layer on the surface of the base material introduced into the vacuum container. Cleans the contaminated surfaces of aluminum (AI) and tin targets, exhausts the vacuum container sufficiently, and simultaneously adjusts the vacuum degree by supplying argon gas to adjust the vacuum degree. A method of manufacturing a coating film metal bearing for an aluminum-tin based diesel engine by a magnetron sputtering process, characterized in that a coating film is formed by connecting a radio frequency power source to a Sn target to form a plasma.