Table of Contents
Application of fiber lasers in welding
The application of laser systems is widespread when it comes to the welding process. Specialists claim that fiber lasers will soon replace traditional welding technologies. The diode-pumped fiber laser systems are most popular due to their low cost, including the ongoing cost of maintenance, spare parts, and being environmentally friendly.
Continuous-wave lasers and beam focusing
Continuous-wave laser systems enable the transmission of uninterrupted laser beam lights that are highly valued in welding. The combination of a fiber laser with the right optics makes the size of the laser beam more focused, for example, a 51μm diameter spot that is 10 times smaller than that of a pulsed laser system.
Advantages of oscillating head technology
Fiber laser systems with an oscillating head provide better welds by applying mirrors that can handle high-power laser beams of 1.5kW. The benefits of lasers with an oscillating head help to achieve high power density that can melt most metal materials and even vaporize them if needed.
Welding types and related issues
There are two types of welds: conduction-limited and keyhole welding. Additionally, the molten pool interacts with the beam of the fiber laser, resulting in inefficient welds when left uncontrolled. The problem appears in deep and narrow keyhole welding, as well as in small welds.
Plasma formation and its influence
Plasma formation also influences the laser beam and leads to scattering effects that degrade welds. The solution to the problem requires the opinions of specialists. Effects such as thermal lens focusing or reflection focusing on the molten pool can lead to a temperature increase in the laser system.
Flexibility and precision of fiber laser technology
“When a gas is heated to a high temperature, it can be ionized and turn into a plasma, where metal vapor and dust can be aggregated, which generates a ‘plasma ball’ scattering the incoming laser beam in multiple directions.” It also decreases the quality of the fiber laser system.
Finally, fiber laser technology is considered to be very flexible compared to fixed fiber optics. It allows for controlling weld depth and width independently. It needs careful attention to such parameters as power, amplitude, frequency, and average speed. Low heat distortion plays a crucial role in laser systems.