Which laser should I choose?
Sheet metal fabricators have the choice of either fiber laser cutters or CO2 laser cutters. Both lasers have been used in the workforce for a number of years, and although they may have the same basic function of cutting sheet metal, there are marked differences. This article describes the basics of how the two lasers work, their advantages, and their disadvantages.
How it works
A bank of diodes produces light. Fiber optic cables channel and amplify the photons to form a beam. Even though no optical mirrors are used, fiber lasers are 200% more efficient at light creation.
The advantages to fiber lasers are plentiful. There are no moving parts or mirrors in a fiber laser which means nothing must be aligned. This results in a lower overall maintenance cost. The insensitivity of the machine leads to lower operating and maintenance cost. Fiber lasers have excellent electrical efficiency when compared to CO2 lasers. This makes them more efficient than CO2 with the added benefits of lower running costs along with being environmentally friendly. Fiber lasers also have an advantage with regard to cutting thin materials. They are close to three times faster at cutting on stainless steel with a 1 mm thickness than CO2 lasers. Finally, fiber lasers have the ability to cut reflective materials such as copper, brass, and aluminum.
The main disadvantage to fiber lasers is apparent with thicker materials. When processing metals thicker than 5 mm, CO2 lasers produce faster, cleaner cuts.
How it works
Excited CO2 molecules release photons that are focused into a beam using optical mirrors and lenses.
CO2 lasers also possess some advantages. As previously stated, CO2 lasers perform better on materials thicker than 5 mm. They leave a smoother finish than fiber laser and perform the cut more quickly. Additionally, CO2 lasers provide a smoother cut edge, especially in materials thicker than 3 mm.
CO2 lasers are very sensitive machines. The mirrors that focus the laser require realignment if they get knocked out of place. The realignment must be done by a specialist, which can be an expensive ordeal. This leads to overall higher maintenance costs. Fiber lasers perform better on thin materials than CO2 lasers do. Finally, unlike fiber lasers, CO2 lasers cannot work with reflective metals. Back reflections could damage the machine irreparably.