Frequently Asked Questions

For different materials, choosing different laser power waveforms can also make the welding effect more delicate. Sometimes even materials that cannot be welded by traditional methods can be obtained by changing the laser power waveform.When selecting the laser output power waveform, under the premise of outputting the same laser energy, the wider the duty cycle, the larger the welding spot; the higher the peak output power of the laser output power waveform, the deeper the welding spot. Customers can explore in the application process to explore the laser output power waveform suitable for your products.

Laser Power
The energy delivered per unit of time by a fiber laser. The power of a laser cutting machine determines its cutting or engraving speed, as well as its ability to penetrate or heat materials. Laser power is a physical quantity that measures the output energy per unit time, and it shares the same unit of measurement as electrical power, using watts.

Welding Speed
Welding speed has a significant effect on the depth of fusion. Increasing the speed reduces the depth of fusion, while too low a speed may result in excessive melting of the material and weld penetration. Therefore, there is a range of welding speeds that are appropriate for a given laser power and thickness of a given material, and the maximum depth of fusion can be achieved at the corresponding speed values therein.

Laser Power Density
The prerequisite for deep penetration welding is to focus the laser beam to achieve sufficiently high power density, thus laser power density plays a decisive role in the formation of weld seams. Laser power also controls the depth of penetration and welding speed. For a certain diameter of the laser beam, increasing the laser power deepens the penetration and accelerates the welding speed.

Peak Power
This is a specific term for pulsed lasers and an important performance indicator for pulse lasers. It represents the highest power that can be achieved by a single pulse. The unit is watt (W).

Pulse Frequency
Pulse frequency, beam spot size, and welding speed need to be matched to achieve the desired overlap rate. Generally, a higher overlap rate leads to smoother welds, but it also reduces the welding speed. When the laser pulse frequency exceeds a certain value, the overlap rate becomes too high, surpassing the welding limit of the material, which may lead to burn-through or the formation of welding spatter.

Pulse Width
Also known as pulse duration, it refers to the duration of a single pulse. Therefore, it is a unit of time measured in milliseconds (ms), microseconds (us), nanoseconds (ns), picoseconds (ps), femtoseconds (fs), etc.

Max Pulse Energy
Refers to the laser energy carried by a single pulse and is the product of peak power and pulse width. The unit is joule (J). For example, if the peak power is 10 kilowatts and the pulse width is 100 nanoseconds, the pulse energy E = peak power * pulse width.

Pulse Repetition Rate

Equivalent to the number of pulses repeated within one second, measured in hertz (Hz).
Average power: It is the laser energy output per unit time in one repetition cycle, unit is Watt (W). Output power = pulse repetition frequency * pulse energy.

Defocus Amount

Defocus amount, also known as focus offset distance, pertains to the separation between the focal point of the laser beam and the surface intended for machining on the workpiece. Altering the defocus amount directly impacts the dimensions of the laser spot, consequently influencing the laser energy density within the irradiation region. There are two types of defocus: positive defocus and negative defocus. Positive defocus occurs when the focal plane is above the workpiece, while negative defocus occurs when it is below. With negative defocus, the power density inside the material is higher than on the surface, resulting in stronger melting and vaporization, allowing the light energy to penetrate deeper into the material. Therefore, in practical applications, negative defocus is preferred when a larger penetration depth is required, while positive defocus is suitable for welding thin materials.

Beam Spot Size

The size of the beam spot is one of the most important variables in laser welding as it determines the power density.

Focal Point Position

The position of the focal point is critical in order to maintain adequate power density when welding. Changes in the position of the focal point relative to the surface of the workpiece directly affect the weld width and depth.

In sheet metal laser manufacturing, the quality requirements for welding strength and appearance are different according to different products. Laser welding has a small heat input, and the heat-affected zone is extremely small, which can effectively improve the welding quality and reduce the time for follow-up work. And some internal structural parts or parts that need to be sprayed later have higher requirements for welding strength and welding speed. DP laser welding machine is undoubtedly the best choice.

Dapeng Laser is a laser equipment R&D manufacturer integrating R&D, manufacturing, sales and service. The company covers more than 200 kinds of laser equipments, including laser cutting machine, laser marking machine, laser welding machine, laser engraving machine and laser cleaning machine products. DP Laser is committed to providing customers with laser processing solutions and professional technical support to become a trusted partner. Please contact our technical team online for customized laser equipment solutions and quotes!

When the temperature is low in winter, in order to ensure the normal use of the laser machine and equipment maintenance, antifreeze will be added to the water tank. So, what happens in hot climates? When working in hot weater, as long as the water tank cannot reach the cooling effect, the equipment will alarm and suspend operation. How to avoid similar situations from happening? The water tank is the key, the size of the water tank determines the operating time to maintain normal temperature. The smaller the water tank, the weaker the constant temperature capability, and the water tank larger the stronger, and there is also certain gap in cost. In order to reduce production costs, many manufacturers also equip with small water tanks, which is why there are price differences.