304 stainless steel pipe welding technology, "partner"

[guidebook] : In the laser welding industry, the use of laser welding stainless steel material workpiece manufacturers is very much, the welding effect of the laser welding machine is also very good, 304 stainless steel material naturally using laser welding is also a very good choice...

304

In the laser welding industry, the use of laser welding stainless steel material workpiece manufacturers is very much, the welding effect of the laser welding machine is also very good, 304 stainless steel material naturally using laser welding is also a very good choice.

304 stainless steel as a kind of austenitic stainless steel, versatile stainless steel material, corrosion resistance, heat resistance is good, and non-magnetic. Corrosion resistance is stronger than the 200 series of stainless steel materials. High temperature resistance is also better in terms of good weldability, welding cold crack and hot crack sensitivity are smaller, stamping bending and other hot workability is good, no hot place, can be as high as 1000-1200 degrees.

In recent years, stainless steel has been more widely used in aerospace, electronic devices, medical devices, nuclear industry, mechanical instrumentation and other aspects of the application of more and more. Therefore, the encapsulation and welding of ultra-thin stainless steel products have become very important. Traditional welding methods are difficult to ensure the quality of welding and forming of thin plates, and laser welding has the advantages of traditional welding can not be compared, can effectively reduce welding defects. 304 stainless steel welding technology research is produced in this context.

Stainless steel in the process of use, a large part of the welding, due to the welding quality directly affects the use of stainless steel parts performance. Stainless steel welded joints are composed of weld metal zone, heat affected zone and base metal (base metal) zone consists of three parts.

Stainless steel using laser welding advantages

Laser welding machine welding compared with conventional welding, low-power pulsed laser seam welding has the advantages of high power density, energy concentration, small heat input, narrow weld and small deformation, etc., and the laser beam can be focused to obtain a very small spot, which can be precisely positioned, and these features make the laser seam welding more suitable for welding small-sized workpieces than other welding methods. For laser welding of ultra-thin stainless steel materials, because the material is very thin, it is easy to vaporize the perforation, to get a continuous, no burn-through weld. The key is the precise control of the parameters.

Laser welding is the use of laser beam excellent directionality and high power density and other characteristics of the work. Through the optical system to focus the laser beam in a very small area, in a very short period of time to be welded to form a highly concentrated energy heat source area, so that the welded material melting and the formation of solid weld joints and seams.

There are two commonly used laser welding methods: pulsed laser welding and continuous laser welding. The former is mainly used for single-point fixed continuous and thin pieces of material welding. The latter is mainly used for welding and cutting of large thick pieces.

First, the characteristics of laser welding processing methods:

1, non-contact processing, do not need to workpiece pressure and surface treatment.

2, small welding joints, high energy density, suitable for high-speed processing.

3, short-time welding, no thermal impact on the outside world, but also on the thermal deformation of the material itself and the heat-affected zone is small, especially suitable for processing high melting point, high hardness, special materials.

4, do not need filler metal, do not need a vacuum environment (can be carried out directly in the air), will not be like an electron beam in the air as the risk of generating X-rays.

5, compared with the contact welding process. No wear and tear of electrodes, tools, etc.

6. No processing noise, no pollution to the environment.

7. Even small workpieces can be processed. In addition, it can be welded through the wall of transparent materials.

8, can be achieved through the fiber optic long-distance, ordinary method is difficult to reach the parts, multi-channel simultaneous or time-sharing welding.

9. It is easy to change the laser output focal length and the position of the welding point.

10、It is easy to be mounted on the automatic machine and robot device.

11, the conductor with insulation layer can be welded directly, the performance of large differences in dissimilar metals can also be welded.

Second, the main parameters affecting the quality of laser welding are welding current, pulse width, pulse frequency, etc., and their effects are mainly as follows:

1, with the increase of current, the width of the weld increases, the welding process gradually spatter, weld surface oxidation phenomenon, and roughness.

2, with the increase of pulse width, the width of the weld seam is also increasing. The change of pulse width has a very significant effect on the effect of stainless steel ultra-thin plate laser welding machine welding. A small increase in pulse width may cause the specimen to be oxidized and burned through.

3, with the increase of pulse frequency, the overlap rate of welded joints increases, and the width of the weld first increases. Afterwards, it basically remains unchanged. Observed under the microscope, the weld is more and more smooth and beautiful. However, when the pulse frequency increases to a certain value, the welding process spatter is serious, the weld becomes rough, and oxidation occurs on the upper and lower surfaces of the weldment.

4, the laser welding of ultra-thin plate material is suitable for the use of positive defocus, in the case of the same amount of defocus, positive defocus laser welding to get the surface of the weld is smoother and more beautiful than the negative defocus.