CN109108464B

CN109108464B - Working method of laser welding tool for aluminum alloy panel for high-speed rail

Info

Publication number: CN109108464B
Application number: CN201811275197.4A
Authority: CN
Inventors: 何建方; 刘少彬; 刘汉杰
Original assignee: DANYANG HONGTU LASER TECHNOLOGY CO LTD
Current assignee: DANYANG HONGTU LASER TECHNOLOGY CO LTD
Priority date: 2018-10-30
Filing date: 2018-10-30
Publication date: 2020-06-16
Anticipated expiration: 2038-10-30
Also published as: CN109108464A

Abstract

The invention relates to a working method of a laser welding tool for an aluminum alloy panel for a high-speed rail, which comprises a longitudinal support and a transverse support, wherein a cushion block is fixedly arranged at the intersection point of the longitudinal support and the transverse support, the cushion block comprises a middle cushion block and a welding seam cushion block, the middle cushion block comprises a horizontally arranged top surface, so that the aluminum alloy panel to be welded can be arranged on the middle cushion block, the welding seam cushion block comprises a welding seam cushion block vertical supporting part and a welding seam cushion block horizontal supporting part which are integrally arranged, the welding seam cushion block vertical supporting part is arranged at the outer side of the welding seam cushion block horizontal supporting part, so that the aluminum alloy panel is supported by the supporting vertical surface of the welding seam cushion block vertical supporting part when being clamped, the areas to be welded at the end parts of two adjacent aluminum alloy panels are arranged on the welding seam cushion block horizontal supporting part, so that inert gas is filled into the plane gas storage tank and the vertical gas storage tank during welding.

Description

Working method of laser welding tool for aluminum alloy panel for high-speed rail

Technical Field

The invention relates to the technical field of aluminum alloy welding equipment, in particular to a working method of a laser welding tool for an aluminum alloy panel for a high-speed rail.

Background

The industrial aluminum profile has the advantages of light weight, excellent forming, high strength, corrosion resistance, long service life, reproducibility, less pollution, low maintenance cost and the like, is unique among a plurality of materials, and is the most popular of high-speed rails. The large-scale use of the aluminum alloy material on the carriage greatly lightens the weight of the high-speed train and makes a central contribution to the high-speed running of the train. The high-speed running of the train is a system project which comprises a plurality of technical conditions and methods, and the light weight of the railway train is an important way for realizing the high-speed heavy load of the train, namely, the lighter the weight of the train and the faster the speed of the train under the same other conditions. Aluminum profiles are certainly the best material for weight reduction, and as early as the 50 s in the 20 th century, some countries developed throughout the world have begun to use aluminum profiles for the manufacture of railway vehicles, including america, canada, japan, russia, germany, france, and the like. Although the strength of pure aluminum is low, the alloy formed by adding a certain amount of elements has higher strength, and the higher specific strength and specific rigidity of the alloy are superior to those of a plurality of alloy steels, so that the alloy becomes an ideal structural material. The tensile strength of the high-strength aluminum alloy is greater than 480MPa, and the high-strength aluminum alloy can completely meet the strength standard of a high-speed train carriage. Meanwhile, the aluminum alloy has good plasticity, can be processed into various sections, has excellent electrical conductivity, thermal conductivity and corrosion resistance, is widely used in industry, and is more and more applied to airplanes and high-speed rails.

The laser welding technology is a metallurgical bonding formed by scanning a welding seam by using a high-energy (102W/cm 2) laser beam and melting metals on two sides of the welding seam by using laser heat energy, and has the advantages of concentrated heating, small heat loss, large depth-to-width ratio of the welding seam, small welding deformation and the like. Laser welding, however, has its own disadvantages due to its beam characteristics: (1) the small diameter of the laser focusing spot leads to high welding assembly precision requirement of the workpiece, and the assembly gap and the misalignment amount are usually less than 0.1mm or 10% of the plate thickness, so that the implementation difficulty of the complex three-dimensional welding structure is increased; (2) because the surface of the aluminum alloy is provided with a layer of oxide film, the melting point is about 2300 ℃, so that the laser is required to have higher power for the laser deep melting welding of the aluminum alloy. (3) The aluminum alloy has low melting point and good liquid metal fluidity, strong metal vaporization is generated under the action of laser beams with concentrated density, and the absorption of the aluminum alloy on laser energy is influenced by metal steam/plasma cloud formed along with the pinhole effect in the welding process, so that the deep melting welding process is unstable, and the defects of air holes, surface collapse, undercut and the like are easily generated on a welding line. Therefore, how to improve the defects of the welding seam of the aluminum alloy laser welding and improve the performance of the welding joint is changed by the invention.

The main defects of the laser welding seam of the aluminum alloy are air holes, surface collapse and undercut, wherein the defects of the surface collapse and the undercut can be improved by laser wire filling welding or laser-arc composite welding; and the defect control of weld porosity is difficult. Some metallurgical porosity may be controlled by pre-weld surface treatment, typically physical mechanical cleaning, chemical cleaning or laser shock cleaning. The technological parameters of the aluminum alloy laser welding process generally mainly include laser power, defocusing amount, welding speed, components and flow of gas protection and the like. The parameters affect the protection effect of the welding area and the stability of the laser deep melting welding process, thereby affecting the weld porosity. The determination of reasonable technological parameters for stabilizing the weld formation is an effective measure for effectively controlling the air holes of the laser weld of the aluminum alloy.

Two surfaces, namely the front surface and the back surface of the welding laser incidence, are adopted in the welding of the aluminum alloy panel for the high-speed rail, and the conventional gas shielded welding is that the front surface is fed with an inert gas shielded molten pool by a protective nozzle, so that the molten pool on the surface is isolated from the air to achieve the protection effect. In the welding of the aluminum alloy panel for the high-speed rail, penetration welding is needed, and a molten pool can be contacted with air on the back surface, so that the aluminum alloy panel is oxidized.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a working method of the aluminum alloy panel laser welding tool for the high-speed rail, which ensures the formation of welding seams and avoids the defects of welding seam pores and oxidation.

In order to solve the technical problem, the laser welding tool for the aluminum alloy panel for the high-speed rail comprises a plurality of vertical supports and transverse supports which are perpendicular to each other, wherein each vertical support comprises a plurality of middle vertical supports and 2 end vertical supports, each transverse support comprises a plurality of middle transverse supports and 2 end transverse supports, a cushion block is fixedly arranged at the intersection point of each vertical support and each transverse support, each cushion block comprises a middle cushion block and a welding seam cushion block, each middle cushion block is fixedly arranged at the intersection point of each middle vertical support and each middle transverse support, each middle cushion block comprises a horizontally arranged top surface, so that the aluminum alloy panel to be welded can be placed on each middle cushion block, a cushion block is arranged at the intersection point of each end vertical support and each middle transverse support, each welding seam cushion block comprises an integrally arranged welding seam vertical cushion block supporting part and a welding seam horizontal supporting part, and each welding seam vertical supporting part is placed on the outer side of each welding seam cushion block horizontal supporting part, the welding joint is characterized in that the welding joint is supported and leaned by a supporting vertical face of a vertical supporting portion of a welding joint cushion block when the aluminum alloy panel is clamped, the to-be-welded areas of the end portions of two adjacent aluminum alloy panels are arranged on a horizontal supporting portion of the welding joint cushion block, a plane gas storage tank is arranged on the horizontal supporting portion of the welding joint cushion block, and a vertical face gas storage tank is arranged on the supporting vertical face, so that inert gas is filled into the plane gas storage tank and the vertical face gas storage tank during welding, the back of the welding position of the aluminum alloy panel is protected by inert atmosphere, and the aluminum alloy panel.

Furthermore, the plane gas storage tank is communicated with the vertical face gas storage tank, and inert gas can enter the vertical face gas storage tank from the plane gas storage tank or enter the plane gas storage tank from the vertical face gas storage tank.

Furthermore, an air inlet channel is obliquely arranged on the horizontal supporting part of the welding seam cushion block, an air outlet of the air inlet channel is communicated with the plane air storage tank, and an air inlet is arranged on the side wall of the horizontal supporting part of the welding seam cushion block.

Furthermore, the cross sections of the plane air storage tank and the vertical face air storage tank are U-shaped.

Further, the end part longitudinal support and the intersection of the middle cross support and the end part cross support are further provided with end part cushion blocks, each end part cushion block comprises a horizontal supporting part and a vertical supporting part which are perpendicular to each other, and the vertical supporting parts are arranged on the outer sides of the horizontal supporting parts so as to be supported by the vertical supporting parts of the end part cushion blocks during clamping of the aluminum alloy panel.

Further, the end part of the welding seam cushion block vertical supporting part is in arc transition.

The working method of the laser welding tool for the aluminum alloy panel for the high-speed rail comprises the following steps:

A. the laser welding tool for the aluminum alloy panel for the high-speed rail is fixed, and the repeated positioning precision is guaranteed.

B. The aluminum alloy panel to be welded is arranged in the aluminum alloy panel laser welding tool for the high-speed rail, the back face of the area to be welded is located at the welding seam cushion block horizontal supporting portion, the middle of the aluminum alloy panel is supported by the middle cushion block, and the two ends of the aluminum alloy panel are clamped by the welding seam cushion block vertical supporting portion of the welding seam cushion block and the vertical supporting portion of the end cushion block.

C. And inert gas is filled into the plane gas storage groove and the vertical face gas storage groove from the gas inlet channel through the gas pipe and the regulating valve, the laser welding equipment is started to weld the front face of the area to be welded of the aluminum alloy panel, the inert gas of the laser welding equipment forms inert gas protection on the front face of the area to be welded, and the inert gas in the plane gas storage groove and the vertical face gas storage groove forms inert gas protection on the back face of the area to be welded.

Further, the inert gas is argon with the purity not lower than 99.999 percent, the speed of the inert gas entering the vertical face gas storage tank and the plane gas storage tank is controlled at 9L/min, and the speed of the inert gas of the laser welding equipment is controlled at 3L/min.

The invention has the technical effects that: compared with the prior art, the laser welding tool for the aluminum alloy panel for the high-speed rail is characterized in that the plane gas storage groove and the vertical face gas storage groove are arranged on the welding seam cushion block, so that inert gas is filled in the gas storage grooves when the aluminum alloy panel is welded, the vertical face gas storage groove is arranged, so that gas can be fed in from the side face during welding, and the advantage that the gas fed in from the side face of the aluminum alloy panel is higher than that from the bottom face of the aluminum alloy panel is that the gas flow fed in from the bottom face can blow local welding beads, the welding bead forming is directly influenced, and the gas fed in from the side face of the aluminum alloy panel can be dispersed; the problem of welding seam blowholes is effectively solved by the double-air-passage protection of the plane air storage tank and the vertical face air storage tank, and meanwhile, the flow time of a welding molten pool can be prolonged by adjusting the defocusing amount, so that the blowholes in the molten pool can be favorably overflowed; the front side and the back side are simultaneously protected by inert gas, so that a U-shaped groove is formed in the back side for storing gas to achieve a protection effect, and the problems that the aluminum alloy panel is in a penetration welding state during welding and a molten pool can be contacted with air at the back side are solved; the air inlet channel is obliquely arranged on the horizontal supporting portion of the welding seam cushion block, and the air inlet is arranged on the side wall of the horizontal supporting portion of the welding seam cushion block, so that inert gas enters the plane air storage tank from the oblique direction, the atmosphere and air pressure in the plane air storage tank are ensured to be more uniform, the air storage tank is entered from the side, the influence of direct blowing of air flow on the welding seam can be avoided, and the welding effect is improved.

Drawings

The invention is described in further detail below with reference to the drawings of the specification:

FIG. 1 is a schematic structural diagram of a laser welding tool for an aluminum alloy panel for a high-speed rail, according to the invention;

FIG. 2 is a schematic perspective view of the weld spacer of the present invention;

fig. 3 is a perspective view of the end block of the present invention.

In the figure: the gas pipe comprises an end cross brace 1, a middle cross brace 11, an end longitudinal brace 2, a middle longitudinal brace 21, a middle cushion block 3, a welding seam cushion block 4, a welding seam cushion block vertical supporting part 41, a plane gas storage tank 42, a vertical face gas storage tank 43, a supporting vertical face 44, an arc transition face 45, a welding seam cushion block horizontal supporting part 46, a gas inlet channel 47, a gas inlet 48, an end cushion block 5, a vertical supporting part 51, a horizontal supporting part 52 and a gas pipe 6.

Detailed Description

Example 1

As shown in fig. 1 to 3, the laser welding tool for aluminum alloy panels for high-speed rail of this embodiment includes 4 longitudinal struts and 5 transverse struts, which are perpendicular to each other, wherein the longitudinal struts include 2 middle

longitudinal struts

21 and 2 end longitudinal struts 2, the transverse struts include 3 middle

transverse struts

11 and 2 end transverse struts 1, a cushion block is fixedly disposed at an intersection of the longitudinal struts and the transverse struts, the cushion block includes a middle cushion block 3 and a welding seam cushion block 4, the middle cushion block 3 is fixedly disposed at an intersection of the middle longitudinal strut 21 and the middle transverse strut 11, the middle cushion block 3 includes a horizontally disposed top surface, so that an aluminum alloy panel to be welded can be supported by the middle cushion block 3, the intersection of the end longitudinal struts 2 and the middle transverse strut 11 is respectively provided with a welding seam cushion block 5, the welding seam cushion block 4 includes an integrally disposed welding seam cushion block vertical supporting portion 41 and a welding seam cushion block horizontal supporting portion 46, each welding seam vertical cushion block 41 is disposed outside the welding seam horizontal supporting portion 46, so that the aluminum alloy panels are supported by a supporting vertical surface 44 of a vertical supporting part 41 of the welding seam cushion block when being clamped, the areas to be welded at the end parts of two adjacent aluminum alloy panels are arranged on a horizontal supporting part 46 of the welding seam cushion block, a plane air storage tank 42 is arranged on the horizontal supporting part 46 of the welding seam cushion block, a vertical surface air storage tank 43 is arranged on the supporting vertical surface 44, the plane air storage tank 42 is communicated with the vertical surface air storage tank 43, the cross sections of the plane air storage tank 42 and the vertical surface air storage tank 43 are U-shaped, the depth of the plane air storage tank 42 and the vertical surface air storage tank 43 is 15mm, the opening width is 5mm, an air inlet channel 47 is obliquely arranged on the horizontal supporting part 46 of the welding seam cushion block, the air outlet of the air inlet channel 47 is communicated with the plane air storage tank 42, the air inlet 48 is arranged on the side wall of the horizontal supporting part 46 of the, and inert atmosphere protection is formed on the back of the welding position of the aluminum alloy panel, so that the aluminum alloy panel is prevented from being in a penetration welding state during welding, and a molten pool can be prevented from contacting with air on the back.

Preferably, the end cushion block 5 is further arranged at the intersection point of the end vertical support 2, the middle cross support 11 and the end cross support 1, the end cushion block 5 comprises a horizontal support portion 52 and a vertical support portion 51 which are arranged perpendicular to each other, and the vertical support portion 51 is arranged outside the horizontal support portion 52, so that the vertical support portion 51 of the end cushion block 5 supports when the aluminum alloy panel is clamped.

Preferably, the ends of the bead block vertical supports 41 are arcuately transitioned to form an arcuately transitioned surface 45.

Example 2

Taking laser welding of an aluminum alloy panel with the trade name of 5083 and an aluminum alloy panel with the trade name of 5052 as an example, wherein the thickness difference of the two materials is 1mm, and in order to ensure the consistency of melting temperature during welding, the welding process of deviating to a thick plate by 0.2mm is adopted; the working method of the laser welding tool for the aluminum alloy panel for the high-speed rail specifically comprises the following steps:

B. The aluminum alloy panel to be welded is arranged in the aluminum alloy panel laser welding tool for the high-speed rail, the welding area is arranged in the welding seam cushion block horizontal supporting portion 46, the middle of the aluminum alloy panel is supported by the middle cushion block 3, and the two ends of the aluminum alloy panel are clamped by the welding seam cushion block vertical supporting portion 41 of the welding seam cushion block 4 and the vertical supporting portion 51 of the end cushion block 5.

C. And (3) filling inert gas into the plane gas storage groove 42 and the vertical face gas storage groove 43 through the gas pipe 6 and the regulating valve by virtue of the gas inlet channel 47, starting the laser welding equipment, welding the front face of the area to be welded of the aluminum alloy panel, forming inert gas protection on the front face of the area to be welded by virtue of the inert gas of the laser welding equipment, and forming inert gas protection on the back face of the area to be welded by virtue of the inert gas in the plane gas storage groove 42 and the vertical face gas storage groove 43.

Specific laser welding parameters: scanning power P =1.4kw, welding speed F =1200mm/min, focus position F =302mm, spot size D =2.5 × 2.5mm, wherein the introduced inert gas is argon gas with purity not lower than 99.999%, the speed of the inert gas entering the facade gas storage tank and the plane gas storage tank is controlled to be 9-10L/min (preferably 9L/min), the inert gas argon gas jet speed of the welding nozzle is controlled to be 2.8-3.5L/min (preferably 3L/min), the incidence angle of the argon gas: longitudinal direction is 85 degrees, and transverse direction is 90 degrees.

It should be understood that the above examples are only for clearly illustrating the present invention and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And such obvious variations or modifications which fall within the spirit of the invention are intended to be covered by the scope of the present invention.

Claims

1. The working method of the laser welding tool for the aluminum alloy panel for the high-speed rail is characterized in that the laser welding tool for the aluminum alloy panel for the high-speed rail comprises a plurality of vertical supports and transverse supports which are perpendicular to each other, each vertical support comprises a plurality of middle vertical supports and 2 end vertical supports, each transverse support comprises a plurality of middle transverse supports and 2 end transverse supports, a cushion block is fixedly arranged at the intersection point of each vertical support and each transverse support, each cushion block comprises a middle cushion block and a welding seam cushion block, each middle cushion block is fixedly arranged at the intersection point of each middle vertical support and each middle transverse support, each middle cushion block comprises a horizontally arranged top surface, so that the aluminum alloy panel to be welded can be placed on each middle cushion block, each intersection point of each end vertical support and each middle transverse support is provided with the welding seam cushion block, and each welding seam comprises a welding seam vertical supporting part and a welding seam horizontal supporting part which are integrally arranged, the welding seam cushion block vertical supporting part is arranged on the outer side of the welding seam cushion block horizontal supporting part, so that the aluminum alloy panels are supported by the supporting vertical faces of the welding seam cushion block vertical supporting part when being clamped, the areas to be welded at the end parts of two adjacent aluminum alloy panels are arranged on the welding seam cushion block horizontal supporting part, the welding seam cushion block horizontal supporting part is provided with a plane gas storage tank, and the supporting vertical faces are provided with vertical face gas storage tanks, so that inert gas is filled into the plane gas storage tank and the vertical face gas storage tanks when being welded;

the plane air storage tank is communicated with the vertical face air storage tank;

an air inlet channel is obliquely arranged on the horizontal support part of the welding seam cushion block, an air outlet of the air inlet channel is communicated with the plane air storage tank, and an air inlet is arranged on the side wall of the horizontal support part of the welding seam cushion block;

the sections of the plane air storage tank and the vertical face air storage tank are U-shaped;

end cushion blocks are further arranged at the intersection points of the end longitudinal supports, the middle transverse support and the end transverse support, each end cushion block comprises a horizontal supporting part and a vertical supporting part which are perpendicular to each other, and the vertical supporting parts are arranged on the outer sides of the horizontal supporting parts so that the vertical supporting parts of the end cushion blocks can support the aluminum alloy panel when the aluminum alloy panel is clamped;

the working process comprises the following steps:

A. fixing the laser welding tool for the aluminum alloy panel for the high-speed rail, and ensuring the precision of repeated positioning;

B. placing an aluminum alloy panel to be welded in an aluminum alloy panel laser welding tool for a high-speed rail, enabling the back of a region to be welded to be located at a welding seam cushion block horizontal supporting part, supporting the middle of the aluminum alloy panel by a middle cushion block, and clamping two ends of the aluminum alloy panel by a welding seam cushion block vertical supporting part of the welding seam cushion block and a vertical supporting part of an end cushion block;

2. The working method of the laser welding tool for the aluminum alloy panels for the high-speed rails according to claim 1, wherein the inert gas is argon with the purity of not less than 99.999 percent, the speed of the inert gas entering the vertical-face gas storage tank and the horizontal gas storage tank is controlled to be 9L/min, and the speed of the inert gas of the laser welding equipment is controlled to be 3L/min.

3. The working method of the laser welding tool for the aluminum alloy panels for the high-speed rails as recited in claim 1, wherein the end portions of the vertical supporting portions of the weld bead blocks are in arc transition.