Views: 15 Author: Leapion Publish Time: 04-26-2022 Origin: https://www.leapion.com/
Laser cleaning is an eco-friendly process used to remove rust, paint, oxide and other contaminants from metal surfaces. Because of its efficiency, it is being used in an increasing number of applications. Laser cleaning requires a pulsed fiber laser (typically 50 watts or more).
Traditional industrial cleaning methods are often seen as tedious (and for good reasons). Rust removal can be time and labor consuming. Oxide removal may involve hazardous chemicals specific to each material that needs to be removed. In some cases, paint removal by sandblasting can damage the metal underneath.
Dealing with these problems usually comes at a significant cost, but laser cleaning is changing this: it is a cost-effective solution that reduces cleaning times and maintenance.
If you are skeptical about these claims regarding laser technology, keep reading for the key facts about what a laser does when removing contaminants and coatings.
Laser ablation occurs when a material layer or a coating is removed with a laser beam. This is the process behind all laser cleaning applications. Take laser rust removal on steel. When the beam hits the surface, molecular bonds in the dust or rust layer are broken and ejected from the substrate. In less technical terms, you can imagine that the layer to be removed is simply vaporized by the laser beam.
A simple way to grasp the importance of the ablation threshold is to compare it to throwing a ball over a wall. If you don't throw it high enough, it will never make it over to the other side. Even if you throw the ball a thousand times, you will always fail. The same applies to laser derusting. You can shoot the laser beam a thousand times but as long as the energy is below the ablation threshold of the material you’re working with, nothing will ever be removed.
Now, every material has different properties and thus different molecular bonds. In other words, each material has a specific ablation threshold. To successfully remove a layer from a given material, the energy transferred by the laser beam must be above the ablation threshold of that particular material.
Let's continue with our analogy. Imagine there was a second, higher wall behind the first one and that a ball was thrown with just enough energy to make it over the first wall, but not enough to make it over the second. The ball would bounce off the second wall and fall in between the two walls. Once again, no matter how many times you throw the ball, you will always get the same result. You will make it past the first wall but never the second.
Since there is an ablation threshold for each material, laser cleaning can discriminate between two or more materials when trying to remove an undesired layer from an object. Given a sufficiently large ablation threshold difference between the materials, it is possible to select a material to be removed (i.e., the one with the lower ablation threshold) while leaving the other material untouched.
For example, the rust ablation threshold is much lower than the threshold for common metals like steel and aluminum. The same goes for paint and oil. This vast gap between two values allows contaminants and coatings to be completely vaporized without any risk of damaging the base material underneath. There's just not enough energy for damage to happen.
If you have any questions about laser cleaning machine, Leapion is here to resolve any of your queries. We specialize in all types of laser technologies. You can contact us and we will be available to assist you.
