Metal is perhaps the most common material that is cut with lasers. There are over one hundred different types of metal, and hundreds of industries around the world use some type of metal, whether at the beginning or at the end of the manufacturing process.
Finding a process that can cut metal efficiently to keep up with the ever-growing demand for products, as well as reducing costs and maintaining only the highest level of safety can seem a tall order. The invention of the laser back in the 1960s, and its development into fiber lasers that are commonly used today, ticked all of these boxes.
Which type of laser should you use to cut metal?
There are three types of cutting processes that you can use to cut metal with a laser; gas, crystal and fiber . Gas cutting is conducted with a carbon dioxide or nitrogen mixture, and crystal cutting, is conducted using nd:YAG (neodymium-doped yttrium aluminium garnet) and nd:YVO (neodymium-doped yttrium ortho-vanadate) crystals. These two processes have been around much longer than fiber-based cutting with a laser, and have a history dating back to the 1960s, whereas fiber laser are a relatively new process.
To put it simply, each of the three cutting processes can be used to cut metal, although gas based methods wasn’t always able to do this so well, but we’ve compared them all here.
Crystal lasers are good for cutting metal, but you would typically only use this process where high power is needed, probably for very thick metal. A crystal laser machine is expensive, run on costly pump diodes, so should you need replacement parts this can start to weigh down heavily on your bank balance! Crystal lasers have a shorter service life than the other types of laser machines, at around 8,000 to 15,000 hours.
Gas laser machines have improved greatly over the last few years, and are now much more adept at cutting metal. It is the most common laser cutting process, and is cheaper to operate than a crystal laser .
However, comparing this to the fiber laser cutting process, the latter is more advantageous when it comes to cutting metal. A gas laser cutting machine can generally cut quicker than a fiber laser, but this only applies to thick metals; for thin metals fiber lasers are quicker.
Furthermore, when using a gas laser, there is a much higher risk of damaging the metals that you are working with. If the gas isn’t completely pure, then the metals may be oxidised and take on a yellow tint in colour. Also, gas laser cutters can’t work well with reflective metals, as the beam is reflected back at the machine, whereas a fiber laser doesn’t have this problem. This is known as flashback damage.
Alongside this, a fiber laser is much less expensive to run, having a long service life of around 25,000 hours, rarely needing maintenance, and only requiring cheap replacement parts should they be needed.
Several businesses and manufacturing plants were interviewed on their thoughts of gas laser cutters vs fiber laser cutters, and it was agreed that the fiber laser setup was the more favourable of the two.
Although it was said that gas lasers are better for heavier plates of metal, fiber lasers are generally faster, uses much less power, can work with reflective metals, and has 50% longer servicing intervals as well as half the amount of servicing costs.