There are two main kinds of lasers used in industry; fibre and gas, the latter which mainly use Carbon Dioxide (CO2). In recent years due to increased cutting speeds and lower running costs, the most popular lasers are fibre. Alpha Production Manager Sean Mccoll, compares the two lasers advantages and disadvantages as well as explaining the sector shift towards fibre.
How does a fibre laser work?
The fibre receives the light source from the resonator (light amplifier) of the laser cutting machine and delivers it to the cutting head which is controlled by the CNC (Computerized Numerical Control; a computerized manufacturing process in which pre-programmed software and code controls the movement of production equipment). In the cutting head, the laser is emitted from the end of the fibre optic cable and refocused through a series of focal lenses into a near perfect dot on the material’s surface. Purged with cutting gases such as nitrogen dioxide and oxygen around the laser, the material to be machined is quickly vaporized in the intense heat and blown away as particles of dust.
How does a CO2 laser work?
Once the CO2 resonator has created enough light, the beam is delivered via a process of reflection and refocusing down an intricate path called a ‘beam path delivery system’. This is then purged with inert gas to keep the path pure, clean and free from any dust that would interfere with the delivery of the full intensity of the laser. Once the laser is reflected to the cutting head, it is refocused and emitted in the same manner as the fibre laser, through a series of lenses and a shield of high velocity cutting gases to purge the machined path.
Advantages of fibre lasers:
No moving parts or mirrors
The fact that it has no moving parts means that your fibre laser is ready to get working from the get-go. And, should it be accidently knocked, none of the parts will come out of alignment which could result in costly production down time.
Lower maintenance costs
Fibre lasers are extremely robust, meaning maintenance costs are dramatically lower, as are operational costs and with ‘fit and forget’ technology there is no maintenance cycle or servicing to worry about.
Fibre lasers are much more efficient when it comes to electricity use, meaning lower running costs and a more environmentally friendly machine. For example, a 3 kW fibre laser uses only a third of the power of that of a comparable CO2 laser.
Advantages and disadvantages of CO2 lasers:
Advantages of CO2 lasers
CO2 lasers work better with thicker materials. Fibre lasers can work with thicker materials, but generally a CO2 laser will leave a surface finish that is smoother.
Disadvantages of CO2 lasers
They are sensitive machines that require alignment, so should this get knocked out of place, usually an expert is required to fix it, resulting in long periods of down time when the laser is not being productive.
This also means they need more regular servicing, and the costs of this maintenance are higher. Alongside this, more power is needed, resulting in higher electrical costs. CO2 lasers also perform slower when cutting thin materials, and aren’t able to work with reflective metals to an exacting standard.
The Bottom Line
CO2 Laser vs Fibre Laser Technology is an argument that is slowly fading from our industry. As fibre laser technology continues to evolve, and with the move towards industry 4.0 smart factory goals, engineers and manufacturers have discovered ways to match the performance of CO2 lasers with fibre. Here at Alpha Manufacturing, the installation of two fibre lasers in the past 5 years, has been critical to the growth of the business. The lower running costs as well as the increased cutting speeds have allowed us to be more responsive to customer demands and played a key part in attracting new business while strengthening relationships with existing customers.
Find out more about our laser cutting solutions here.