What precisely is laser engraving, and how does it work?
It’s a technique of burning materials with high-intensity lasers, resulting in fumes that are used to engrave strong, long impressions. The laser beam acts like a chisel, removing layers from the material’s surface and cutting lines into it. A laser is utilised to address small areas with massive amounts of energy so that heat may be generated. With the help of The Engraving People, we’ve broken down everything there is to know about laser engraving in this post.
Is it better to laser engrave or laser etch your ideas?
When it comes to deciding which laser marking technology is appropriate for your project, there are a few things to think about:
- The resistance of the mark to fade: its ability to be readable in extreme circumstances
- The time it takes to mark a surface with the laser:
- The suitability of the marking procedure to the material being marked
Laser engraving with metal etching is frequently utilized on metal components that will be subjected to a variety of usage conditions or surface treatments. Steel and aluminium may both be engraved (anodised and die-cast aluminium).
The most important aspect of this approach is that it can produce enhanced readability of 2D symbols after post-process treatments. Shot blasting, e-coating, and heat treatment are all used to tackle the most challenging traceability issues. However, if the most durable identifiers aren’t required, laser etching is frequently utilized since it is a high-speed method that doesn’t need as much ablation.
The most common metals etched with a laser system are steel, aluminium, anodized aluminium, lead, magnesium, and zinc. Laser annealing is also used to engrave stainless steel metals.
Solid to Gas: How It Works in a Nutshell
When a laser is used to etch the material surface, it melts. Laser engraving sublimes the substance surface by evaporating it, as opposed to melting it. When a substance’s temperature rises, its molecules absorb thermal energy. The molecules shed this heat when the substance reaches 300°F (150°C). However, because the material does not change from solid to liquid and back to gas after absorbing enough thermal energy, it never becomes a liquid.
The laser engraving machine must immediately and uniformly apply enough heat to the substance’s surface in milliseconds in order for it to attain its vaporization temperature. When it comes to sublimation, laser engravers are tough machines.
When the temperature rises above this level, materials are evaporated into vapours. As a consequence, if you acquire a laser system, it should always include a fume extraction device and an air knife to protect the workplace and the laser’s lens.
For this, fibre lasers are the finest engraving tools since they operate at a wavelength that is appropriate with metals.
What Is the Best Way to Engrave High-Contrast, High-Quality Symbols?
Examine enlarged photographs of the surface to see how chaotic it is. The light is trapped in deep grooves (the engraving depth may reach up to 0.5 mm), making permanent impressions darker than they would be without the laser engraving procedure.
When you laser engraves a surface, you have two methods for achieving contrast.
- The first (and quicker) approach, on the other hand, creates a contrast between the base material and the etched black marks. If the exposed surface colour is light enough to produce strong contrast, this technique is only recommended.
- The second (and considerably longer) approach, which uses a laser, is more accurate. The laser system employs both laser engraving and laser etching to create black marks and white markings.