Some types of metal , like copper alloys and certain aluminium grades are too reflective for CO2 lasers. This is a limitation that hampers different use-cases. The first fibre lasers were introduced in at EuroBlech. The different laser beam conveying methods allowed cutting highly reflective metals.
Now, metals like aluminium, brass, copper and galvanised steel are available for laser cutting. Fibre lasers are simpler and more durable. The laser light is first created by banks of diodes. It is then channelled through optic cables, where it gets amplified. The cables are doped with rare earth elements like erbium, thulium and the like. These elements are used for amplifying the light. Finally, the lens focuses the light to form a laser beam ready for cutting.
The new system needs no gases, mirror realignments, nor warming up. A big advantage of fibre lasers is its high energy conversion rate. The significant difference comes mainly from the low losses in heat generation.
This makes 2 kW fibre lasers comparable to more high power CO2 counterparts. The major improvements spur on engineers to continue developing this revolutionary technology. This is an indication for the future.
Although the majority of the market is still in the grasp of CO2 lasers, fibre lasers are catching up. Now, an increasingly large share of new sales is reserved for the latter.
The maintenance costs of fibre lasers is a big selling point. There are fewer moving parts and less adjustments to make. That results in lower down-times due to maintenance. Today, the fibre laser is significantly quicker when cutting thin metals. CO2 still beats fibre when cutting thicker materials 10 mm and more with its better edge quality.
Altogether, the future seems bright for fibre lasers. Lasers are different. The lightwaves they produce all have very similar wavelengths and which travel together in phase.
That is, the peaks of the light waves they produce are all synchronized together. Because a laser beam is made up of multiple waves that are all in phase with one another, they are very bright, narrow, and can be focused onto a small, precise area.
They can also focus a lot of energy onto this small area. When you were a kid, did you ever use a magnifying glass to focus sunlight onto a leaf to start a fire? Well, an industrial laser cutter works along the same principle.
Within the cutting machine, a laser beam is produced and then reflected off of a mirror onto the focusing plate. The plate acts like the magnifying glass you played with as a kid, focusing the already powerful beam into a small, intense point. That much power concentrated into a point can result in the rapid heating, melting and even vaporization of the material it is used on. United Kingdom. Iran Islamic Republic of. Syrian Arab Republic. Angola Angola. Cameroun Cameroon. Congo, Democratic Republic of.
Dzayer Algeria. Guinea Ecuatorial Equatorial Guinea. Madagasikara Madagascar. Moris Mauritius. Sao Tome and Principe. Seychelles, Sesel Seychelles. Tanzania, United Republic of. Uburundi Burundi. Western Sahara. Aotearoa New Zealand. Belau Palau. Brunei Darussalam. Dhivehi Raajje Maldives.
Korea Democratic People's Republic of. Micronesia Federated States of. Improvements in accuracy, edge squareness and heat input control means that the laser process is increasingly replacing other profiling cutting techniques, such as plasma and oxy-fuel.
There are many state of the art laser machines on the market for cutting purposes, which can be used to cut metals, woods and engineered woods. The laser cutting process involves focusing a laser beam, usually with a lens sometimes with a concave mirror , to a small spot which has sufficient power density to produce a laser cut. The lens is defined by its focal length, which is the distance from the lens to the focused spot.
The critical factors which govern the efficiency of the process are the focused spot diameter d and the depth of focus L. The depth of focus is the effective distance over which satisfactory cutting can be achieved. The laser focal spot diameter and the depth of focus is dependent on the raw laser beam diameter on the lens and the focal length of the lens. For a constant raw laser beam diameter, decrease in the focal length lens of the focusing lens results in a smaller focal spot diameter and depth of focus.
For a constant focus length lens, increase in the raw beam diameter also reduces both the spot diameter and the depth of focus. To allow comparison between lasers with different beam diameters we therefore use a factor called the focus f-number, which is the focal length, F, divided by the incoming raw beam diameter, D.
Because these two requirements are in conflict with each other, a compromise must be made. The only other consideration is that the shorter the focal length, the closer the lens is to the workpiece, and therefore more likely to get damaged by spatter from the cutting process.
In fact, it would be possible to optimise focal length for each material thickness, but this would involve additional set-up time when changing from one job to another, which would have to be balanced against the increased speed. In reality, changing the lens is avoided and a compromised cutting speed used, unless a specific job has special requirements. Nowadays most of industrial sheet metal laser cutting is carried out using two types of lasers: CO 2 and fibre.
The CO 2 laser carbon dioxide laser is generated in a gas mixture, which mostly consists of carbon dioxide CO 2 , helium and nitrogen. Such a laser is electrically pumped using an electric discharge. CO 2 lasers typically emit at a wavelength of Those used for material processing can generate beams of many kilowatts in power.
It also produces a smoother surface finish when cutting thicker materials. Laser cutting of sheet metals historically started with CO 2 lasers. Most CO 2 laser cutting machines are three-axis systems X-Y, two-dimensional positioning control with a Z-axis height control. There are, however, a number of ways of achieving the X-Y movement: either moving the laser head, moving the workpiece or a combination of both.
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