Laser Marking to mark stainless steel is every day when cutting and welding pieces of steel. Laser markings are very effective, and it is possible to get these done in a fraction of the time that it would take a regular diamond cutter. In simple terms, when a laser beam is shone onto a stainless steel object, it causes the metal to be marked and then afterwards, it is etched to produce a permanent indented spot. Marking Stainless Steel uses this process to have a very durable and consistent finish on Stainless Steel.
Marking Stainless Steel - An Overview There are various ways in which laser marking can be used on stainless steel, including in stamping and engraving, in addition to other means. In general, there are three types of laser marking that are used on stainless steel to produce an indented spot; surface marking, laser ablation and dark marking. These techniques differ because the first type marks the surface using a fiber optic beam, whereas the other two utilize a chemical reaction on the metal to produce the dark spot on the surface. With surface marking, a dye is spread onto the metal surface, where a hard, black line is then created as the laser marking comes into contact with the material. This kind of laser marking is best used to produce precision surface welds and to produce flat finished surfaces.
Engraving: Laser engraving is also known as laser etching. In engraving, a laser beam is aligned with an intricate crystal or another metallic surface to be etched so that the spot is engraved on that particular surface. The laser markings that come into contact with the metal surface are produced using a chemical reaction between the laser beam and the natural oxidation layer on the metal surface. The purpose of this technique is to create smooth, even, highly-defined lines with minimal surface irregularities.
Laser annealing: Laser annealing is the other common technique used for laser marking stainless steel. In this process, a heat source is used for annealing the metal before applying the marking compound. The compound is applied to the work-piece in question, and the work-piece is placed in a freezer. The laser marking process is completed once the work-piece has cooled down sufficiently to prevent permanent fusing of the heat-sensitive areas of the annealed stainless steel surface. The laser marking process is also helpful in producing subtle gradients on thin stainless steel.
Nitriding: A third common technique in stainless steel laser marking is called nitriding. In this technique, a hardener is applied to a work piece that will form a hard oxide layer on the work-piece after it cools. The oxide layer acts as a barrier to prevent the hardening agents from interacting with the surface of the stainless steel. When the work-piece is cooled below room temperature, the oxide layer will solidify and produce a solid stain marked on the stainless steel.
Fiber Laser Etching: Fiber laser etching is a relatively new technique in marking stainless steel. A low-energy laser (excitation pulse light) is used for anodizing the steel while it is in its resting phase. A robotic arm then uses the excitation pulses to anodize the steel. This method effectively creates subtle gradients on light-colored steel by using a uniform energy beam on the steel at various wavelengths.
Combination Marking System: The combination marking system is an enhanced version of two previously mentioned techniques. The most apparent difference is adding an anodized shield to the anodized part of the laser marking stainless steel. This configuration yields almost identical results to the oxide-enhanced variety of marking. The only real difference is that the shielded portion is not used when performing combination laser marking on colored steel.
Digital Laser Engraving: Another option for laser marking stainless steel is digital laser engraving. This system yields a large number of textured outcomes by using a laser beam and computer-assisted software. This is a relatively new technique, and there are still many refinements and development steps to be done before it is considered cost-effective. For a large number of applications, however, this combination marking configuration is economical and reliable.