WO2015156493A1

WO2015156493A1 - Method for manufacturing friction stir spot bonding portion of metal matrix composite

Info

Publication number: WO2015156493A1
Application number: PCT/KR2015/001499
Authority: WO
Inventors: 홍성태; 천두만; 염영진; 이정희; 정용하; 오현석
Original assignee: 울산대학교 산학협력단
Priority date: 2014-04-09
Filing date: 2015-02-13
Publication date: 2015-10-15
Also published as: KR101514681B1

Abstract

The present invention provides a method for manufacturing a friction stir spot bonding portion of a metal matrix composite, comprising the steps of: providing a mask; laminating a carbon material on a first metal material using the mask; disposing the first metal material on a second metal material; and bonding the first metal material and the second metal material using friction stir spot welding (FSSW), thereby achieving low-cost and high-efficiency characteristics of NPDS and FSSW and easily manufacturing a composite at a desired location. Furthermore, since NPDS can adjust the amount of laminated carbon powder, it is possible to accurately predict the mechanical property of a spot bonding portion, and since powder is laminated with a sufficient adhesive force, it is possible to manufacture a neat composite.

Description

Metal matrix composite friction stir welding method

The present invention relates to a method for producing a metal matrix composite friction stir point joint. More specifically, the carbon-based particles are laminated with a Nano-Particle Deposition System (NPDS), and then the surface is subjected to friction stir spot welding (FSSW) to manufacture a metal base composite spot junction. A method for producing a metal matrix composite friction stir point joint.

In general, metal matrix composites (MMC) are those in which carbon materials are added to the metal base to improve the mechanical performance of the metal base, and are usually based on lightweight metal materials such as aluminum (Al) and magnesium (Mg). It is manufactured by.

Carbon materials, which have a higher modulus of elasticity and superior thermal and electrical conductivity than ordinary metallic materials, are generally nano or micro sized graphite, graphene, carbon Nanotubes (CNT, carbon nanotube) are used.

For example, a metal matrix composite material may be manufactured to simultaneously have a lightweight aluminum sheet and a friction stir process (FSP) to simultaneously have a high strength and thermal conductivity of a carbon base and a high carbon material. Friction Stirring (FSP) is a tool that rotates at a high speed to cause local plastic deformation of the surface of the material to change the microstructure of the material surface to a desired shape to improve the mechanical properties of the surface.

Meanwhile, friction stir spot welding (FSSW) is one of the solid state bonding techniques derived from friction stir welding (FSW) and overcomes the disadvantages of conventional resistance spot welding (RSW). It is a technology that can improve the mechanical properties of the weld by supplementing.

1 is a conceptual diagram showing a general friction stir spot welding method (FSSW).

Referring to FIG. 1, the tool 10 used in the friction stir spot welding method FSSW includes a threaded probe 11 directly inserted into the to-be-joined materials 1 and 2 contacted up and down, Shoulders rubbed on the upper surfaces of the to-be-joined materials 1 and 2, and grips (not shown) capable of engaging the shoulders 12 to the main shaft.

The process of friction stir spot welding is as follows.

First, the tool 10 is rotated to insert the probe 11 into the to-be-joined materials 1 and 2 (Plunging).

Next, heat is generated by mutual friction between the probe 11 and the shoulder 12 and the joined materials 1 and 2, and the peripheral joined materials 1 and 2 are softened by the frictional heat, and the tool 10 With the plastic flow of the material by stirring, the materials on both sides of the bonding surface are forcibly mixed to form the point junction 20 (Bonding).

Next, the friction stir spot welding method (FSSW) of the to-be-joined materials 1 and 2 is finished by drawing out the probe 11 and the shoulder 12 of the tool 10 from the to-be-joined materials 1 and 2 (Drawing out). .

One of the main factors that determine the quality of the point joint is mechanical properties such as strength, and the point joint 20 formed by the friction stir spot welding method (FSSW) has a weak point of the hook 21, so that the starting point of fracture Becomes

Embodiments of the present invention seek to provide a method of making a metal matrix composite having point junctions with good mechanical properties.

According to one or more exemplary embodiments, a method of manufacturing a metal matrix composite material includes: providing a mask, laminating a carbon material on a first metal material using the mask, placing the first metal material on a second metal material, and Bonding the first metal material to the second metal material using friction stir spot welding (FSSW).

Preferably, the step of laminating the carbon material, it may be characterized in that the carbon material is accelerated to be laminated at high speed through a transport gas at room temperature.

Preferably, the step of laminating the carbon material, it may be characterized in that for laminating the carbon material using a nanoparticle lamination system.

Preferably, the carbon material comprises at least one material selected from the group consisting of graphite, graphene, carbon nanotubes (CNT), expanded graphite, and mixtures thereof. It may include.

According to the method for manufacturing a metal matrix composite material of the present invention, there is an effect that NPDS and FSSW have a low cost, high efficiency characteristics and can easily produce a composite material at a desired position.

In addition, NPDS can control the amount of carbon material powder to be laminated, so it is possible to accurately predict the mechanical properties of the point bonding portion, and the powder is laminated with sufficient adhesive force, it is possible to produce a clean composite material.

2 is a flow chart of a method for producing a metal matrix composite material which is a preferred embodiment of the present invention.

3 is a schematic diagram of a nanoparticle stacking system (NPDS) for carrying out a method for producing a metal matrix composite material.

4 is a cross-sectional view showing the lamination of carbon particles using a mask in the present invention.

It is a block diagram for implementing a friction stir spot welding method.

It is sectional drawing which shows the state of friction friction spot welding method implementation, and a joining part after implementation.

Hereinafter, a method of manufacturing a metal matrix composite friction stir point joint according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. First, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are assigned to the same components as much as possible, even if shown on different drawings. In addition, the following will describe a preferred embodiment of the present invention, but the technical idea of the present invention is not limited thereto and may be variously modified and modified by those skilled in the art.

2 is a flowchart of a method for manufacturing a metal matrix composite material, which is a preferred embodiment of the present invention, and FIG. 3 is a schematic diagram of a nanoparticle stacking system (NPDS) for implementing a method for manufacturing metal matrix composite material, and FIG. It is sectional drawing which shows the lamination | stacking of carbon particle using a mask, FIG. 5 is a block diagram for performing a friction stir spot welding method, and FIG. 6 is sectional drawing which shows the junction state after implementation and the friction stir spot welding method.

2 to 6, the method for manufacturing a metal matrix composite material includes providing a mask 40 (100S), and laminating a carbon material on the first metal material 35 using the mask 40 ( 200S), disposing the first metal material 35 on the second metal material 36 (300S) and joining the first metal material 35 and the second metal material 36 using a friction stir spot welding method. The process proceeds to step 400S.

In the step 100S of providing the mask 40, the mask 40 serves to form a stacked shape of the carbon material. The mask 40 can be modified in size or shape according to the area and shape of the carbon laminate, and the powder injection zone 42 of the carbon material is determined by the shape of the mask 40. In one embodiment of the mask 40 may be provided in a ring shape.

In the step of stacking the carbon material on the first metal material 35 using the mask 40 (200S), the carbon material is laminated in the nano-particle deposition system (NPDS), aerosol deposition (Aerosol Deposition) Or by impinging the carbon material directly on the metal material without any treatment in a powder state through a high-speed transfer gas using a cold spray or the like.

NPDS is a room temperature dry lamination system that eliminates the disadvantages of existing high temperature conditions or process conditions including chemicals, and is an efficient process technology capable of laminating both ceramic and metal materials.

The NPDS apparatus 30 is connected to the powder supply apparatus 33 for supplying carbon powder, the nozzle 34 connected to the powder supply apparatus 33 to become an outlet of the carbon powder, and the powder supply apparatus 33 for carbon. An air compressor 32 for injecting powder to the outside along the nozzle 34, a stage 37 on which the first metal material 35 and the second metal material 36 are placed, and the inside of the NPDS are vacuumed to form an NPDS device 30. ) Is provided with a vacuum pump 38 for maintaining the internal cleanliness.

The mask 40 is located at the outlet of the nozzle 34, and the carbon material injected from the nozzle 34 may be laminated in a predetermined shape.

As an example of the carbon material, any one of graphite, graphene, carbon nanotube, expanded graphite, or a hybrid mixture thereof may be used. .

More specifically, the graphite is a material having a high modulus of elasticity and excellent thermal conductivity and electrical conductivity compared to a general metal material, and for this reason, a graphite or carbon nanotube, such as a carbon material or a metal or polymer as a base material It is often considered as a reinforcement for composites. In addition, the graphene is not only stable in structural properties, but also has a density of 2 g / cm 3 or less, which is lighter than metal materials, has a very high tensile strength of several tens of GPa, and has a high thermal conductivity. It is widely used in materials, etc., and is recognized as a very important material in the field of materials in the future. Furthermore, when the graphene, which is a two-dimensional material, is hybridized with the carbon nanotube, which is a one-dimensional material, the concentration of percolation limit required for conduction can be lowered, and the thermal conductivity can be further increased. Has

In the step 300S of disposing the first metal material 35 on the second metal material 36, the first metal material 35 on which the carbon material is laminated is disposed on the second metal material 36 to be disposed on the first metal material 35. The coupling between the second metal materials 36 is prepared.

In the step 400S of joining the first metal material 35 and the second metal material 36 using a friction stir spot welding method, friction stir spot welding (FSSW) is performed at a position where a carbon material is laminated. Is carried out.

Friction stir welding (FSSW) is a joining method having a three-step process of repositioning after the insertion of the rotating member 50, except for the conveying step of the tool during the friction stir welding process, the welding holding time. This inserts the rotating member 50, which is a non-consumable tool that rotates at a high speed, into the target material to apply friction heat between the tool and the material and plastic flow of the material.

5 and 6, the first metal material 35 is disposed on the second metal material 36 to be bonded, and the carbon material is laminated on the portion to be bonded, and then friction is performed using the non-consumable rotating member 50. Stir welding is performed to form the FSSW joint 52.

In addition, NPDS can control the amount of carbon material powder to be laminated, the powder is laminated with a sufficient adhesive force it is possible to produce a clean composite material.

The above description is merely illustrative of the technical idea of the present invention, and various modifications, changes, and substitutions may be made by those skilled in the art without departing from the essential characteristics of the present invention. will be. Accordingly, the embodiments disclosed in the present invention and the accompanying drawings are not intended to limit the technical spirit of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by the embodiments and the accompanying drawings. . The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

Claims

Providing a mask,

Laminating a carbon material on a first metal material using the mask;

Disposing the first metal material on the second metal material; and

Bonding the first metal material to the second metal material using friction stir spot welding (FSSW);

Metal matrix composite friction stir point joint manufacturing method comprising a.
In claim 1,

Laminating the carbon material,

Method for producing a metal-based composite material friction stir point joint portion characterized in that the carbon material is accelerated and laminated at high speed through a transport gas at room temperature.
The method of claim 2,

Laminating the carbon material,

A method for producing a metal matrix composite friction stir point joint, characterized in that the carbon material is laminated using a nanoparticle lamination system (NPDS).
The method according to any one of claims 1 to 3,

The carbon material,

Metal matrix composite friction stir point comprising at least one material selected from the group consisting of graphite, graphene, carbon nanotubes (CNT), expanded graphite, and mixtures thereof Method of manufacturing the joint.