Laser Surface Preparation Treatment with Fiber Lasers
What is surface preparation treatment?
Simply this is the preparation of a surface through a treatment (the name speaks for itself!). The reason for the surface to be prepared is virtually always to increase the adhesion capability of coatings.
Industry professionals say that the most important factor, which influences the long-term performance of coatings is the quality with which the surface had been prepared. Traditionally this was achieved chemically or mechanically, but a modern-day emerging approach is to treat surfaces with laser technology.
Surface preparation typically occurs before tasks such as anodising, galvanising, painting, plastering, plating (e.g. chrome and nickel), sealing (e.g. with silicon), tiling, waterproofing, welding and other tasks too.
Materials which may require preparation
Many materials many require surface preparation. The most typical materials are carbon composites, concrete, metals (especially steels), plastics (e.g. vinyl flooring), rubber and wood, etc.
Surface level contaminants
A range of contaminants could be on the surface layer, including:
- Existing coatings – sometimes existing coatings of paint, varnish, etc. may need to be removed
- Surface imperfections – items such as welding joins, cuts, marks, etc.
- Residues – various deposits on the surface such as dirt, dust, grease and oil, etc.
- Organic – moss, fungi and any other living organisms
- Oxidation – most typically rust and various stains
Traditional surface preparation treatments
Traditional techniques applied include:
- Abrasive blast cleaning – is the appliance of a force where a stream of abrasive material is applied to a surface to smooth/shape it by removing surface level contaminants. There are many forms of this blasting technique including bead, bristle, dry ice, hydro, micro, sand, vacuum, wet and wheel
- Chemical cleaning – this is the appliance of chemicals to clean the surface, these include acids (e.g. sulphuric and hydrochloric), various alkalines and also a variety of ready-made industry chemical solutions for surface preparation
- Manual cleaning – sometimes treatment can be manually applied through a series of tasks such as hand wire brushing, smoothing/sanding, scraping, chipping and similar tasks. Sometimes power tools (e.g. sander) can be used in this process
- Pressure water cleaning – this is another form of blast type cleaning, where water pressure blast impurities off the surface. This is most often a combination of low and high pressure combination blasts
Laser ablation as a new alternative technique
Laser ablation works through a laser beam being directed at the surface of the material (where the contaminants appear). Layer by layer the contaminant evapourates through thermal reactions, which have a by-product of cleaning the surface level of a material. The laser beam creates shockwaves on the layer of pollutant, which cause the fragments to gradually disappear, any micro particles are easy to tidy up.
The laser beam can be very precisely programmed and controlled creating very fine, top-quality cleaning, where only the contaminant is removed, there is no damage to substrate materials.
In addition, laser ablation has many advantages, which are summarised below.
Advantages of fiber laser surface preparation
There are many advantages of a fiber laser-based approach to surface preparation, we have listed some of the advantages below:
- Chemical free – no chemicals are used with a laser-based approach. Chemicals introduce their own risks such as corrosion, damage to substrate materials, discolouration, toxicity, waste products
- Contactless approach – there is no need for contact to be made with the material when the surface is being prepared. This reduces risk to the material and the user, the only contact is remotely via the laser beam
- Minimal residue – apart from a little dust (which might not even arise), there is no residue with fiber laser preparation treatment whereas traditional approaches can have waste by-products, such as chemical slurries
- No corrosion – relating to the use of chemicals is corrosion. With a fiber laser there is zero % chance risk of any form of corrosion damage to the material lying underneath the surface
- No tooling – apart from the laser itself there is no tooling required (e.g. power tools, blasting equipment, etc.)
- Precision and control – no other method offers such precision and control. The laser operator controls exact depth and surface contaminants are carefully removed layer by layer
- Speed – Lasers prepare surfaces very fast, in a time-pressured world this is an important benefit, especially when compared to manual methods, which are time-consuming and therefore expensive on labour
SPI Lasers – we are here for you!
SPI Lasers manufacture two fiber laser ranges – redPOWER® Continuous Wave (CW) Fiber Lasers and redENERGY® Pulsed Fiber Lasers, either is suitable for surface preparation treatment. Which laser type is best for your organisation will depend on your exact requirements, which are likely to be wider than this individual task?
Invest in one of our fiber lasers, which will deliver the functionality needed for surface preparation treatment including ablation and cleaning. Our lasers will also prove valuable for a wide-range of other tasks including cutting, drilling, engraving as well as additive manufacturing, marking and welding – to name but a few!
Contact us today to discuss surface preparation treatments and other laser processes. Our contact details are available at this page.
Image Credit: Wikipedia
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