Laser cleaning is one of the more modern versions of the cleaning process and has rapidly replaced more traditional methods such as dry-ice blasting or media blasting due to the numerous benefits that it provides.
It offers these benefits as it works in a significantly different way to the processes that have preceded it. Furthermore, using a fiber laser as the medium also works in a much different way to other types of cleaning methods. We have explored this in more detail below and explained why laser-based cleaning is the most efficient, safe and cost-effective cleaning solution on the market.
How does laser cleaning work?
The aim of this process is simple; to clean the surface of a material (e.g. metal, plastics, ceramics, etc.) that it is working with.
So how does the process actually work? A laser beam is pulsed at the surface of a material, irradiating and vaporising the layer until the desired depth of ablation has been reached. The pulse’s output power and wavelength can be controlled, offering the user a great deal of control when it comes to vaporising a material’s surface with a high degree of accuracy.
How does the vaporisation work? The contaminants that are on the surface layer of the material, such as the rubber, paint, dirt, grease, oils, etc. absorb the beam as it is directed at it. The heat of this beam quickly irradiates this material, removing the contamination from the surface.
Why is this process better than more traditional methods?
A key question that we are frequently asked is “How does fiber laser cleaning work differently to the other more traditional methods?”. There are some key problems that lasers have helped to address and solve.
Firstly, other methods were contact processes, meaning they were abrasive and damaging to the materials that they were working with. Take media blasting, for example, which essentially acts like a pressure washer, but with pressurised air, to blast a material until it is clean. It gets the job done, but it often affects the material that you don’t want to damage below!
Laser-based cleaning, on the other hand, is non-contact and non-abrasive, and so will only irradiate the material that you want to get rid of. This makes the process in particular, ideal for cleaning intricate and textured materials.
You also have a great deal of control over the beam, meaning you can achieve the desired depth that you want to. Further to this, you can irradiate the whole surface layer of a material, or a much thinner layer, say the topcoat of paint, but not the primer below. Or, should you wish, you can just clean a very small section. If using another process which simply blasts the material, it is hard to enjoy such a high level of control.
One of the key benefits in the way that cleaning with a laser works is that not much waste is left over due to the irradiation process; the substrate is simply vaporised rather than left as waste. The majority of the waste that is left over comes as dust particles and can be easily collected and removed by the user.
As if all the above isn’t enough, the cleaning with lasers is also much faster, leaving staff more able to complete other work and not spend all of their time cleaning!
What are the advantages of the process?
So, the key characteristics of how the process works, which differentiates it from more traditional methods, are that:
- It is a much safer process
- It is more efficient with cleaning being completed much more quickly
- No harmful cleaning chemicals are needed in the fiber laser cleaning process. These are potentially harmful to staff, the environment and also the object being cleaned (e.g. corrosion)
- It offers the user a higher level of accuracy and control
- The process is totally non-contact, which is safer for the laser operative than traditional techniques and
- There is a greater focus on a higher quality end result
Some Examples of Fiber laser cleaning applications
There are a wide-variety of applications for fiber laser cleaning, these include:
- Artwork restoration – artwork such as ceramics, ornaments, paintings, prints, vases, etc. can all be cleaned using laser-based cleaning techniques
- Labelling and marking – approaches can be used to ablate surfaces (e.g. metal and plastic) to leave a label or mark below. This ideal for the creation of product codes and barcodes, etc.
- Mould cleaning and de-oiling – moulds constantly need cleaning and/or deoiling. This has great appeal in certain industries, e.g. manufacturing (especially of food)
- Surface preparation treatment – such as to remove paint, mould, or to prepare surfaces for treatment. Surfaces can easily gather or contain contaminants such as carbon, rust, dirt, grease and rubber, and laser cleaning offers an efficient and environmentally-friendly way of removing these.
- Stonework restoration – various types of stonework will become dirty over time, these include monuments, headstones, sculptures, statues, etc. Fiber lasers will clean stone to a higher standard and with less damage to stone than traditional methods
- Traffic film removal – layers of traffic film deposit themselves over time on cars, planes, buildings, etc. these can all be cleaned/ablated off
How does a fiber laser work?
Just as there is more than one type of cleaning process, there is also more than one type of laser process too. The three main types of laser are; crystal, gas, and fiber. Here at SPI Lasers, we only manufacture fiber lasers, and this type offers additional benefits over the other types of laser medium.
How does a fiber laser work? An optical fiber, which has been doped with the rare earth element of Erbium, acts as the beam source, this is able to achieve a high power, high-quality laser beam, but cost-effectively too.
Within this fiber is the laser medium, where the erbium atoms are contained. The photons that are emitted, to create the beam, are also within this fiber core. In this core, you’ll find a highly effective refracting system, called a Bragg Grating.
The laser medium, Bragg Grating and pump source combined help to produce a high quality and stable laser beam.
Why is this better than using other types of laser?
There are many reasons that fiber lasers have quickly gained popularity over other types of laser. The laser beam is generated inside the fiber itself, and so the beam produced is extremely stable. Other laser sources, on the other hand, rely on a fine alignment of mirrors, and should these be knocked, it can be hard to realign them.
The stable beam that is produced is also of an extremely high quality too. It’s straight, it can be highly accurate to a small degree, and it offers a high level of power too.
Finally, they are an efficient source too. They are easy to cool, have a much longer service life than other types of laser, and our ‘Fit & Forget’ technology means they’ll never need any maintenance either.