By Alex Fraser on September 16, 2022
Industrial Lasers
Ever since the first laser was built in 1960, laser physicists have been pushing the limits of laser technology.
In the manufacturing industry, engineers are constantly developing solutions made possible by high-power lasers. They are mainly used to mark, clean, texture, weld, and cut materials faster and meet short cycle times in production lines.
High-power laser systems generate considerable energy levels compared to typical lasers. While there is no official definition for how much power is considered “high-power”, most laser experts agree that high-power lasers are at least a few hundred watts.
Here is an overview of the subjects covered in this article:
- High-Power Lasers in the Manufacturing Industry
- Average Power vs. Peak Power
- Laser Power Categories
- How are High-Power Lasers Different?
- Power Differences for Single-Mode & Multimode Lasers
High-Power Lasers in the Manufacturing Industry
High-power lasers are efficient, precise, and eco-friendly alternatives to a range of technologies used in manufacturing. They are commonly used for laser marking, laser cleaning, laser texturing, laser welding, and laser cutting in fast-paced production lines.
Laser Marking
This video shows a 500W pulsed fiber laser that creates deep engravings at high speed. The identifiers remain readable after a shotblasting treatment.
Laser marking is the process of creating permanent identifiers on parts and products to implement, for example, industrial traceability. Higher power lasers are typically used to mark hard metals, to process more parts faster, or to engrave deeper into the material.
Laser Cleaning
A 200W pulsed fiber laser is used to remove phosphate coating from specific areas used for assembly. Assembly areas need to be coat free to prevent reliability problems.
Laser cleaning, also called laser ablation, vaporizes a range of contaminants (oxides, oils, coatings, electrolytes, etc.) into dust and fumes. The process ensures that metal surfaces are perfectly clean before operations like welding, coating, and assembly.
Laser cleaning can be used to replace masking in coating applications. Instead of masking sensitive areas and coating the rest, parts are fully coated, then selective laser removal is used to remove coatings from precise areas.
Ultra-high-power pulsed lasers offering up to 3kW of power can be used to clean large surface areas, a feat that is generally considered too long with lasers of 500W or less. They can also clean localized areas and complex geometries at very high speed.
Laser Texturing
In this video, a high-power single mode fiber laser is used to clean and texture cylindrical battery casings. This process ensures the good bonding quality of thermal adhesives in structural battery packs.
Laser texturing modifies the surface properties of metal surfaces by changing their texture and roughness. It is used to prepare surfaces for processes like thermal spray coating and adhesive bonding.
Laser Welding
A high-power pulsed laser is used to weld hundreds of cylindrical battery cells to a busbar. Robot arms apply pressure to guarantee zero gap between the busbar and the cell terminals.
Laser welding is the process of joining two metal surfaces together by melting them. Continuous-wave lasers are typically used for industrial welding because they offer deeper penetration into the material. Pulsed lasers are used to weld sensitive components that require a lower heat affected zone and shallower penetration, such as when welding EV battery components.
Laser Cutting
A 6000W continuous-wave fiber laser is controlled by a CNC machine to cut thick metal plates into workpieces.
Laser cutting uses high-power lasers to vaporize materials (such as wood, glass, plastic, or metal) and create a cut edge with extreme precision. It is used in several industries, including electronics, medicine, aerospace, automotive, and semiconductors.
Average Power vs. Peak Power
To better understand what high power means, it’s essential to understand the difference between average power and peak power.
Laser systems are named after their average power, which is the average amount of energy generated by the laser over time. Higher power lasers can generate more energy over the same time. For example, a 200W laser generates twice the amount of energy that a 100W laser generates during one second.
The peak power is the highest energy level that can be generated by the laser. While continuous-wave lasers always operate at their peak power, pulsed lasers release short bursts of energy at a set repetition rate. Some of the technologies used to generate laser pulses and reach higher energy levels are mode-locked and q-switched lasers.
At Laserax, a 100W pulsed laser can release laser pulses of 100 nanoseconds each that reach 10,000W of peak power. Lasers of more than 100W reach the same peak power but release more pulses per second. For example, our 500W pulsed lasers can release five times more pulses per second than our 100W pulsed lasers.
Laser Power Categories
At Laserax, we categorize optical powers as follows:
| Power Level Category | Output Power |
|---|---|
| Regular power | 10W to 100W |
| High power | 200W to 500W |
| Ultra high power | 500W to 3kW |
These are pulsed fiber lasers used for material processing, such as laser marking, laser cleaning, laser texturing, and laser welding. Their 1,064 nm wavelength is ideal to process metals.
How are High-Power Lasers Different?
Different power configurations have different requirements. Typically, high-power lasers have a larger laser source, generate more heat, and for this reason need temperature control to cool them down during usage. Common methods include air cooling and water cooling.
Since high-power lasers generate more heat, they also operate using higher-quality optical components that prevent overheating and burning.
Laser scanners are an example of components. These mirrors rotate in the laser head to move and redirect the laser beam to precise locations. To prevent them from burning, they have a specialized coating that provides heat protection. For the same reason, high-power lasers use a quartz lens.
Power Differences for Single-Mode & Multimode Lasers
The more powerful the laser, the higher the chances that the laser is categorized as multimode, but what does that mean?
Let’s go over the difference between single-mode and multimode.
Heat Management
Single-mode lasers have a smaller optical fiber core, which means that laser light is concentrated and travels in a smaller area. For high-power applications, this complicates heat management. Multimode lasers, on the other hand, have a larger core that facilitates heat management. This allows them to be used for laser applications that require ultra-high power.
Beam Quality
Single-mode lasers have a better beam quality, which means the laser beam can be focused to a smaller spot. This allows them to be used to etch parts, which is required for laser marking and laser texturing applications.
Speed
Multimode lasers can reach must faster laser cleaning speeds because of their larger spot size and higher energy levels.
Fiber Cable Length
Multimode lasers have access to longer fiber cables, sometimes reaching up to 100m. In comparison, single-mode lasers are often limited to 5m or 8m of cable length. This makes multimode lasers ideal for robot integrations.
Conclusion
High-power lasers offer new possibilities for manufacturers. These eco-friendly solutions add speed and precision to manufacturing processes, but they require advanced expertise to ensure safety and efficiency.
If you have a project requiring a laser, you can get in touch with one of our laser experts.
