When selecting an effective marking method, every application is unique; different materials interact differently with laser energy. A variety of factors, from materials to finishes can affect your final outcome. There are a number of laser marking processes to choose from such as ablation, engraving, etching and more. Choosing the right method to achieve a permanent mark for your application depends on the material and type of mark required.
Compared to silk screen printing, vibro or dot peening, machine routing engraving, chemical etching, laser marking is faster, cleaner, durable, and much more versalite.
Laser marking is growing in demand from manufacturers because increases in compliance regulations are requiring more and more manufacturers to track and trace products throughout their lifecycle. For example, the durability of the mark is critical when marking medical devices, firearms and electronic components. In these circumstances and many others, serial numbers cannot wear off due to frequent use or exposure to harsh environments.
Not only can laser marks be very small and precise; they are also much less likely to fade — a big concern when marks are small, because there is less of a mark there to begin with. Depending on material being marked, laser marks can be highly temperature and corrosion resistant because tthe equipment does not come into physical contact with the material being marked.
All else being equal, manufacturers obviously prefer a marking method that is faster, better and costs less than the alternatives. In most cases, laser marking is superior to other methods.
Laser marks are produced by a laser beam operating under computer control. Typically, the only preparation required is to remove any potential contaminants and program the laser to make high quality marks. The part (or sheets of parts) are then placed under the laser at a relatively high speed and then marked based on very configurable program settings.
By contrast, chemical etching takes longer because it requires much more prep work. This includes covering the part in a protective coating, which is then mechanically cut wherever the underlying material will be exposed to the etchant (typically acid). The part is then bathed in the acid to produce the mark, after which the protective material and any acid residue are washed away.
Routing engraving can also be a much slower process. With this method the tool, or cutter, cuts into the surface of the material to a predetermined depth and produces a groove in the same shape as the cutter. So, unlike a laser, whose beam width and power are adjustable, the mechanical cutting tool (of fixed dimension) may need to make multiple passes to achieve the same mark. The cutting tool will wear out and must be routinely replaced — which also takes time — while the laser beam does not wear out.
Light is an inherently more precise marking agent than inkjet (spraying ink on a surface), chemical etching, or mechanical cutting — achieving tolerances down to within 0.001’’ inches. That makes lasers very appropriate for applications like micro coding — i.e., marking very small product codes on very small parts, such as marking model numbers or logos on ceramic substrates used in electronics manufacturing. This factor is key, especially when combined with the next factor.
Another advantage of using lasers for marking is that the marks tend to be highly versatile, especially when it comes to the range of materials that can be marked. Factors such as the thinness of the material, the ability to handle intricate shapes (both of the part itself and the mark), and the size of the mark (as discussed under precision) make laser marking a highly flexible way to achieve durable, quality marks. Lasers can mark a very wide range of materials, including:
In fact, Lasers can mark very thin materials (down to 0.003’’ foil) without destroying the material — a thinness that is impossible to achieve with either chemical or mechanical etching. Lasers also have the edge when it comes to the intricacies of the shape to be marked and the kind of parts that can be marked. Since a laser beam is light, it can be directed under computer control with a high degree of accuracy and flexibility to create virtually any pattern on practically an unlimited variety of shaped and sized parts.
Lasers have an advantage over other marking methods that involve inks or chemicals because there are no materials left behind that weren't already there to begin with — making laser marking ideal for applications requiring clean environments such as biomedical implants or virtually any medically related tool.
In summary, selecting the right marking method can obviously have a big impact on product profitability, the speed with which the product can get to market, and the service lifetime of the product after it leaves the factory. For many products, laser marking has tremendous advantages on all three fronts. To learn more about the advantages of laser marking, read our Tech Brief about why medical device makers like laser marking.
We can address permanent identification marking needs such as:
Our customers trust us to make the right decisions about the kind of laser marking services required to achieve durable, cost-effective solutions to their permanent identification needs. The laser marking team of experts at Accumet can provide clean, distinct marks, with optimal repeatability, and fast delivery. Contact us to get the right laser mark for your next project.