SHINHOP laser

The laser welding machine often processes different categories of workpieces. Sometimes, the welding effect is affected by the specifications and materials of the workpieces. However, these situations can generally be resolved by setting relevant parameters to achieve good processing results. But ordinary users may not have this common knowledge, so today, our SHINHOP laser equipment company will share with you the relevant parameter settings that affect the quality of the laser welding machine's welding process, including laser output power, laser welding speed, laser beam quality adjustment, pulse width, defocus amount, and protective gas.
1. The impact of output power and welding speed on penetration depth.
The impact of the laser pulse waveform of continuous pulse lasers on welding quality.
1. For welding high-reflective materials such as copper, aluminum, gold, and silver, these metal materials are highly reflective, meaning that the workpieces have a low absorption rate of laser light, resulting in less energy absorption. Therefore, achieving welding becomes more difficult. Thus, when welding, in addition to needing a high-power laser, the waveform should also be adjusted to a peak laser waveform.
2. For ferrous metals like iron and nickel, which have low surface reflectivity, it is advisable to use rectangular waves or slow decay waveforms.
However, this waveform is not suitable for high repetition rate seam welding, as it can easily cause spatter and form irregular small holes.
2. Seam welding waveform:
The seam welding waveform is the curve of laser power changing with welding time. This type of waveform is very important during sealing welding.
When welding begins, the rise in laser power is relatively slow, and at the end of welding, the power will also decrease. Therefore, there may be uneven welding before and after. Using a seam welding waveform can reduce such defects and achieve better welding results.
3. Pulse width (for pulse lasers):
The pulse width of light is one of the important parameters for YAG solid-state lasers. It determines whether the material will melt. To ensure that there is no violent vaporization on the surface of the material during laser welding, it is usually set so that the surface temperature of the material reaches the boiling point when the pulse stops.
The longer the pulse width, the larger the diameter of the weld point. With the same interval, the deeper the penetration.
4. Protective gas:
The type of protective gas, gas flow rate, and blowing method are also important welding process parameters that affect welding quality.
Common protective gases include nitrogen (N2), argon (Ar), helium (He), and mixed gases of argon and helium.
Under normal conditions, when welding carbon steel, argon (Ar) is suitable; for stainless steel, nitrogen (N2) is appropriate; for titanium alloys, helium (He) is used; and for aluminum alloys, a mixture of argon (Ar) and helium (He) is recommended.
The size of the gas flow rate should be determined based on the actual welding environment. When using high-power continuous lasers for welding, coaxial blowing can be used, and for high-power continuous welding, side blowing methods can be employed.
The role of protective gas:
During the laser welding process, plasma can easily occur. Plasma has the effects of absorption, refraction, and reflection on the laser. Protective gas can usually be used to expel or weaken it.
5. Defocus amount:
The necessary defocus amount during light welding is due to the high power density at the center of the laser spot, which can easily evaporate into holes. The positive and negative defocus affects the surface of the workpiece, distributing the power density more evenly.
There are two methods of defocusing:
Positive defocus and negative defocus. Positive defocus is better when a larger penetration depth is required.
Defocus method:
Under certain laser power and welding speed, when the focus is within the welding position range, maximum penetration depth and good weld shape can be achieved.
From the above description, when performing high-speed continuous welding, to ensure welding quality, it is necessary to set relevant suitable parameters through the existing equipment. Users can adjust different parameters to achieve good welding results, but attention should be paid to the following two aspects.
1. A stable laser is required; therefore, good beam quality and stable output power are prerequisites for achieving good welding quality. If users are using a hard optical path laser, they need to maintain and clean it regularly. At the same time, the surface of the workpiece to be welded also needs to be dusted to maintain a clean workpiece surface, which is beneficial for the normal output of the laser on the workpiece surface.
2. Different workpiece materials require corresponding parameter settings during welding. Choosing the appropriate laser power, laser welding processing speed, laser waveform, and gas is essential to create a suitable processing environment for welding materials to achieve high-quality welding processing.