阅读说明：本技术 一种预开槽式搅拌摩擦焊方法 (Pre-slotting type friction stir welding method ) 是由 孙屹博 张媛 于伟 孙亚强 于 2021-07-26 设计创作，主要内容包括：本发明涉及焊接技术领域,具体公开了一种预开槽式搅拌摩擦焊方法,本方法在搅拌摩擦焊前的预处理中在被焊件中的金属板上加工出一条通槽,然后再进行板材的装夹和焊接,通槽可以促使搅拌摩擦焊的过程中被搅拌的材料向通槽处挤压流动,使接头能够成形良好,使焊缝处无明显的气泡、隧道、孔洞等缺陷,提高了焊接接头性能,同时加工简单且成本较低,可在实际生产过程中广泛应用。(The invention relates to the technical field of welding, and particularly discloses a pre-slotting friction stir welding method, which comprises the steps of processing a through groove on a metal plate in a welded piece in the pretreatment before friction stir welding, then clamping and welding a plate, wherein the through groove can promote the stirred material to flow towards the through groove in the friction stir welding process, so that a joint can be well formed, the welding seam has no obvious defects of bubbles, tunnels, holes and the like, the performance of the welded joint is improved, meanwhile, the processing is simple, the cost is lower, and the pre-slotting friction stir welding method can be widely applied to the actual production process.)

1. A pre-slotting friction stir welding method is characterized by comprising the following steps:

s1, performing welding pretreatment on a metal plate (1) and a polymer plate (2), processing the metal plate (1) and the polymer plate (2) into a required shape, and processing a through groove (3) on the surface of the metal plate (1);

s2, overlapping the metal plate (1) and the polymer plate (2) and placing the metal plate (1) and the polymer plate (2) on a workbench of friction stir equipment, placing the metal plate (1) above and the polymer plate (2) below, and clamping the metal plate (1) and the polymer plate (2) on the workbench by using a clamping mechanism;

s3, starting a welding tool, and controlling the needleless stirring head (4) to be arranged above one end of the through groove (3) at a set rotating speed;

s4, control needleless type agitator head (4) insert downwards in leading to groove (3), until no needle type agitator head (4) reach the shaft shoulder volume of pushing down of setting for, and make no needle type agitator head (4) keep the shaft shoulder volume of pushing down of setting for, with constant rotational speed and welding speed, along leading to groove (3) of metal sheet (1) welds, until no needle type agitator head (4) reach the other end of leading to groove (3), will no needle type agitator head (4) lift up to withdraw from.

2. A pre-slotting friction stir welding method according to claim 1, wherein in step S1, the through-slots (3) are rectangular or zigzag in shape.

3. A pre-slotting friction stir welding method according to claim 1, wherein in step S1, the height of the through slots (3) is smaller than the height of the metal plate (1), the length of the through slots (3) is smaller than the length of the metal plate (1), and the width of the through slots (3) is smaller than the width of the shaft shoulder of the pin-less type stirring head (4).

4. A pre-slotted friction stir welding method according to claim 1, characterized in that in step S2, said metal sheet (1) is placed with its through slot (3) facing upwards.

5. The pre-slotting friction stir welding method according to claim 1, wherein in the step S2, the clamping mechanism comprises a clamp (6), a pressing plate (7) and a screw (8), the pressing plate (7) presses two side edges of the metal plate (1), the clamp (6) is positioned above the pressing plate (7), and the clamp (6) clamps the metal plate (1) and the polymer plate (2) below the pressing plate (7) on the workbench through the screw (8).

6. The pre-slotting friction stir welding method according to claim 1, wherein in step S3, the rotation speed of the pin-less type stirring head (4) ranges from 1000r/min to 1600 r/min.

7. A pre-grooved friction stir welding method according to claim 1, wherein in said step S4, said pin-less type stirring head (4) is vertically inserted into said through groove (3).

8. The pre-slotting friction stir welding method according to claim 1, wherein in the step S4, the shaft shoulder pressing amount of the pin-less type stirring head (4) is in the range of 0.1mm-1 mm.

9. The pre-grooved friction stir welding method of claim 1 wherein said welding speed is in the range of 30mm/min to 80mm/min in step S4.

10. A pre-slotted friction stir welding method according to claim 1, characterized in that said metal sheet (1) is an aluminum alloy sheet.

Technical Field

The invention relates to the technical field of welding.

Background

Along with rail transit, the continuous development of structural engineering changes, the design requirement to the structure constantly improves, xenogenesis material connection structure appears thereupon, xenogenesis material connection structure can the superior performance of two kinds or more than two kinds of materials of full play, show out respective bright spot, satisfy the requirement to the material under the different situation simultaneously, however because physical and chemical properties difference is great between the xenogenesis material, bring great degree of difficulty for the welding, the requirement of xenogenesis material welding can not be satisfied in traditional welding, use friction stir welding to weld the xenogenesis material usually, friction stir welding technique is as new solid phase joining technique, compare great advantage with traditional welding technique. In the friction stir welding process of the dissimilar materials of the metal material and the polymer, a large amount of heat is generated between a stirring tool rotating at a high speed and a welded piece, so that the material is plasticized, and then the material is extruded and molded by flowing, so that the welded piece is connected. When the stirring tool moves along the welding direction of the welded piece, an instant cavity is formed behind the stirring pin, the plasticized material below the shaft shoulder of the stirring tool and in front of the stirring pin is continuously extruded and flows into the instant cavity, and if excessive friction heat is generated before the stirring tool and the welded piece, the plasticized material overflows from the shaft shoulder, and a sawtooth-shaped defect is formed; if too little friction heat is generated, the material is not fully plasticized, the flowing property is poor, an instant cavity behind a stirring pin cannot be fully supplemented, welding defects are formed on the surface of a welding seam, and the welding defects mainly comprise defects of flash, unfilled surface, incomplete root penetration, bubbles, tunnels, holes, cracks and the like. In view of the above problems, it is necessary to develop a novel pre-grooved friction stir welding method to overcome the problems of the existing friction stir welding technology.

Disclosure of Invention

In order to solve the problems of the existing friction stir welding, the invention provides a pre-slotting friction stir welding method.

The technical scheme adopted by the invention for realizing the purpose is as follows: a pre-slotting friction stir welding method comprises the following steps:

s1, performing welding pretreatment on a metal plate and a polymer plate, processing the metal plate and the polymer plate into required shapes, and processing a through groove on the surface of the metal plate;

s2, overlapping the metal plate and the polymer plate on a workbench of friction stir equipment, placing the metal plate above and the polymer plate below, and clamping the metal plate and the polymer plate on the workbench by using a clamping mechanism;

s3, starting a welding tool, and controlling the needleless stirring head to be arranged above one end of the through groove at a set rotating speed;

and S4, controlling the needle-free stirring head to be downwards inserted into the through groove until the needle-free stirring head reaches a set shaft shoulder pressing amount, keeping the set shaft shoulder pressing amount of the needle-free stirring head, welding the needle-free stirring head along the through groove of the metal plate at a constant rotating speed and welding speed until the needle-free stirring head reaches the other end of the through groove, and lifting and withdrawing the needle-free stirring head.

Preferably, in step S1, the through slots have a rectangular or saw-tooth shape.

Preferably, in step S1, the height of the through groove is smaller than the height of the metal plate, the length of the through groove is smaller than the length of the metal plate, and the width of the through groove is smaller than the width of the needle-free stirring head shoulder.

Preferably, in step S2, the metal plate with the through slot is placed facing upwards.

Preferably, in step S2, the clamping mechanism includes a clamp, a pressing plate, and a screw, the pressing plate presses the edges of the two sides of the metal plate, the clamp is located above the pressing plate, and the clamp clamps the metal plate and the polymer plate below the pressing plate on the workbench through the screw.

Preferably, in the step S3, the rotation speed of the needleless stirring head ranges from 1000r/min to 1600 r/min.

Preferably, in step S4, the needle-free stirring head is vertically inserted into the through-groove.

Preferably, in step S4, the pressing amount of the needle-less type pin is in the range of 0.1mm to 1 mm.

Preferably, in the step S4, the welding speed is in a range of 30mm/min to 80 mm/min.

Preferably, the metal plate is an aluminum alloy plate.

According to the pre-slotting friction stir welding method, the through groove is machined in the metal plate to enable the stirred material to flow to the through groove in the friction stir welding process, so that a joint can be well formed, the defects of obvious bubbles, tunnels, holes and the like do not exist at the welding seam, the performance of the welded joint is improved, and meanwhile, the pre-slotting friction stir welding method is simple to machine, low in cost and capable of being widely applied to the actual production process.

Drawings

FIG. 1 is a schematic top view of a metal sheet according to an embodiment of the present invention;

FIG. 2 is a schematic cross-sectional front view of a metal sheet according to an embodiment of the present invention;

FIG. 3 is a schematic illustration of a clamp prior to friction stir welding of a metal plate with a polymer in accordance with an embodiment of the present invention;

FIG. 4 is a schematic view of a friction stir welding operation of a metal plate and a polymer according to an embodiment of the present invention.

In the figure: 1. the device comprises a metal plate, 2 a polymer plate, 3 a through groove, 4 a needleless stirring head, 5 a welding line, 6 a clamp, 7 a pressing plate, 8 and a screw.

Detailed Description

The embodiments of the present invention will be described in further detail with reference to the drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

The invention discloses a pre-slotting friction stir welding method, which comprises the following steps:

s1, carrying out welding pretreatment on a metal plate 1 and a polymer plate 2, processing the metal plate 1 and the polymer plate 2 into a required shape, as shown in figures 1 and 2, processing a through groove 3 on the surface of the metal plate 1, wherein the through groove 3 can promote a plasticized material below a shaft shoulder of a stirring tool to flow into the through groove 3, and preventing welding defects;

the metal plate 1 can be an aluminum alloy plate, the through grooves 3 are positioned at the lap joint positions of the metal plate 1 and the polymer plate 2, the through grooves 3 can be rectangular or zigzag, and the height H of the through grooves 3₁Less than the height H of the metal plate 1 and the length D of the through groove 3₁Less than the length D of the metal plate 1 and the width L of the through groove 3₁Is less than the width d of the shaft shoulder of the pin-free stirring head 4;

s2, overlapping the metal plate 1 and the polymer plate 2 and placing the metal plate 1 and the polymer plate 2 on a workbench of friction stir equipment, as shown in figure 3, placing the metal plate 1 above and the polymer plate 2 below, and clamping the metal plate 1 and the polymer plate 2 on the workbench by using a clamping mechanism;

in the friction stir welding and clamping process, the pin-free stirring head 4 rotating at a high speed and the welded piece are subjected to friction stir welding, so that the temperature of the welded piece is increased, the polymer plate 2 is excessively melted in consideration of the overhigh temperature, the metal plate 1 is arranged above, the polymer plate 2 is arranged below, heat is transferred from the welded surface of the metal plate 1 to the lap joint position of the aluminum alloy and the polymer plate 2, and therefore the metal plate 1 and the polymer plate 2 are welded, the metal plate 1 with the through groove 3 is arranged upwards, the clamping mechanism comprises a clamp 6, a pressing plate 7 and a screw 8, the pressing plate 7 is pressed at the two side edges of the metal plate 1, the clamp 6 is arranged above the pressing plate 7, and the metal plate 1 and the polymer plate 2 below the pressing plate 7 are clamped on the workbench through the screw 8 by the clamp 6;

s3, starting the welding tool, and controlling the needleless stirring head 4 to be arranged above one end of the through groove 3 at a set rotating speed;

the rotating speed range of the needleless stirring head 4 can be 1000r/min-1600 r/min;

s4, as shown in a figure 4, controlling the needleless stirring head 4 to be downwards inserted into the through groove 3 until the needleless stirring head 4 reaches a set shaft shoulder pressing amount, enabling the needleless stirring head 4 to keep the set shaft shoulder pressing amount, welding along the through groove 3 of the metal plate 1 at a constant rotating speed and welding speed until the needleless stirring head 4 reaches the other end of the through groove 3, and lifting and withdrawing the needleless stirring head 4;

the pin-free stirring head 4 can be vertically inserted into the through groove 3, the range of the pressing amount of the shaft shoulder of the pin-free stirring head 4 can be 0.1mm-1mm, and the range of the welding speed can be 30mm/min-80 mm/min.

The embodiments of the present invention have been presented for purposes of illustration and description, and are not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiment was chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated.