Laser welding machine operation flexibility, wide range of applications, is now highly sought after industrial processing tools. Laser welding is mostly used for welding of metal materials, laser welding machine through the high intensity laser beam radiation to the metal surface, prompting the metal to dissolve after cooling and solidification. Compared with the traditional welding machine, laser welding machine has the advantages of high processing quality, small deformation, double the efficiency and so on. In order to achieve better welding results, reduce heat effects and ensure strength and hardness. We take Maktronics laser welding machine as an example to introduce the factors affecting the effect of laser welding processing.
Power
The thickness of the material determines how much power is needed to use the laser welding machine. In the process of laser welding, too much or too little output power will have a certain effect on the melting depth effect.
Demonstration machine: MCWlaser 1500W handheld welding machine
Sample: 2mm stainless steel
As you can see through the video: the output power has a great influence on the thickness of the plate, not only affecting the appearance quality, but also affecting the mechanical properties of our welding process, therefore, during the commissioning process, it is recommended to prioritise the confirmation of the effective power range for a better alignment.
Focal length
Focal length refers to the welding of the material surface from the focused laser beam minimum spot distance, because the laser focus is the centre of the spot, the power density is too high, easy to evaporate into a hole, away from the laser focus, the power density distribution is relatively uniform. Therefore, in the process of welding, we need to change the distance from the focal point to the surface of the material (this distance is also known as the amount of out-of-focus), in order to get a better welding effect, the size of the amount of out-of-focus can change the power density and spot, which has a certain effect on the welding quality.
Defocus is further divided into positive defocus and negative defocus. When using positive defocus, the penetration depth decreases, the fusion width increases slightly, and weld spatter decreases; when negative defocus is adopted, the penetration depth increases, fusion width increases slightly, and weld spatter decreases; while when the defocus amount F=0( Positive focus), the laser power density increases, and spatter will be generated during welding. In actual application, when welding thin plates, the penetration depth is small, so it is suitable to use positive defocus; when the penetration depth is large, use negative defocus (if the defocus is too far, the effect will not be obvious, and the energy is easier to disperse).
Width
The width refers to the specified width formed by the laser beam reflecting back and forth at a certain speed on the reflective mirror at a specific rotation angle. When the width is small, concentrated and high-density laser energy will be obtained; when the width is large, laser energy for a larger area will be obtained.
2mm stainless steel Different width effects
The weld seam width directly affects the weld seam performance, and produces certain changes to the depth-to-width ratio. Under constant speed and swing frequency, when the width is reduced, the width of the weld seam and the heated area on the material surface are reduced, the penetration depth is increased, and the welding performance is stable. When the width increases, the weld width and material surface heating area increase, the energy distribution is not concentrated, and the penetration depth decreases. For thick materials, the better the aspect ratio, the better the weld performance.
5mm carbon steel
Frequency
The frequency mainly affects the appearance shape of the weld and the quality of the weld. In the case of constant speed, the laser frequency is reduced, the overlap rate of welding points is reduced, and the surface of the weld seam is relatively rough; if the laser frequency is too high, welding slag or penetration problems are also prone to occur. During the welding process, the appropriate welding frequency can be selected according to the processing materials and welding requirements to ensure a certain overlap rate, and the weld seam will be smoother and cleaner.
Taking the MCWlaser handheld laser welding machine as an example, when the oscillation frequency is 20Hz, the shape of the weld seam is neat and the penetration effect of the weld seam is relatively shallow. Appropriate oscillating frequency can achieve good welding effect. During the welding process, if there is no specific requirement on the appearance and performance, we suggest that the frequency range can be adjusted to 14Hz-20Hz when using our laser welding machine.
Speed
In terms of speed, high-speed welding will make the penetration shallower. Generally, it is recommended to use high-speed welding when welding thin plates or materials with better performance, and vice versa. During the welding process, the speed will also affect the aesthetics of the weld. Low-speed welding is prone to sagging, and high-speed welding will cause uneven welds. In addition, the effect of laser welding will also be affected by various factors such as gas, material absorption rate and waveform. In the actual welding case, we can flexibly adjust the main parameters of laser welding according to the processing requirements, and conduct multiple experiments to achieve better welding results.
The parts and components manufactured by laser welding technology can not only meet the excellent performance of the application field, but also can significantly improve the production efficiency. Compared with traditional welding technology, although the initial investment cost of laser welding is relatively large, its welding effect cannot be ignored. The gradual maturity of laser welding technology will bring more possibilities for innovation and upgrading in the industrial field.
