As engraving by LASER continues to be a popular method of imprinting, engravers are consistently discovering new applications for this unique process.  While CO2 lasers continue to prosper, they do have some limitations.  For engravers looking to further expand into new markets while offering their customers new processes and products, there is the YAG laser marker.

What is a YAG?

The YAG laser differs from the more popular CO2 Laser in the way the light source is generated. CO2 lasers generate their laser light by electrically exciting a combination of gases (carbon dioxide, nitrogen, and helium), and then focusing the light through a special Lens. YAG lasers generate their light source through a combination of a glass crystal and electronics. The glass crystal is actually a rod composed of Ytrium Aluminum Garnet: Thus, the acronym, "YAG".

There is also a growing generation of YAG lasers on the market called solid state diode pumped lasers which have the advantage of using 220 volt Power, more energy efficient, are more compact in design, more user friendly, and have lower price tags.

A YAG laser works similarly to a CO2 laser by vaporizing the material on which it is focused.  In order to effectively produce a mark, the light generated by the laser needs to be absorbed by the material it is processing.  The Beam of light produced by a YAG laser is absorbed by highly thermal or ferrous materials.  This does include most metals. Non-ferrous materials, including wood, do not absorb this type of Laser Beam.  Other materials that will engrave well with a YAG include certain plastics, glass, ceramics, marble, leather, and acrylic.

The most popular applications for YAG high Speed  markers include industrial parts marking, bar coding, batch coding, date coding, medical parts marking, military parts marking, and high volume advertising specialty parts imprinting, and tag and label manufacturing.

YAG laser marking systems use a special system of mirrors and lenses to deliver the laser beam to the work piece. Laser power does vary and can range from 5 watts on up. What you need will depend largely on the material you are marking and desired effect.

Pros

YAG laser marking provides a non-contact method of imprinting. There are no tools that need replacing, and product deformation from faulty or worn tooling is non-existent.  

The mark is permanent, clean and concise. Today's systems are fast and efficient, engraving up to 32 characters a second. The equipment comes integrated with a computer, and is able to run off of most popular graphics software packages, and/or proprietary software developed by the system manufacturer.

YAG marked parts also eliminate the need for labels and/or tags that may not adhere to the product as needed, or in the case of some aviation and medical products, may not be permitted by government regulations.

YAG lasers do not need gas to run, so the laser does not have to be recharged. 

Additionally, YAG laser systems can oftentimes be integrated into assembly lines for greater efficiency in the marking of parts. 

Cons

The YAG laser is a more expensive piece of equipment, costing $20,000 and more for a new machine. There are machines available on the used market for substantially less. However, it remains an expensive technology. 

YAG lasers are potentially harmful to the human eye, so safety concerns are greater  than with a CO2 laser system.  OSHA, ANSI and local regulations do differ with this type of laser, and extra precautions are required.

The marking field is typically smaller with a YAG, which can be limiting for some applications. Also, YAG laser systems were initially developed for industrial purposes, and graphics applications, have not been as widely developed for the YAG as they have for the CO2 lasers.

Maintenance and repair costs are generally greater with a YAG as compared to a CO2 laser engraving system.   Also, the machine may require special technicians to work on it as it tends to be a fairly sophisticated piece of equipment.

Conclusion

While a YAG laser marking system may not be fro everyone, it can open up new opportunities for engravers. Is a YAG laser in your future? Talk to current customers, local industries, and manufacturing firms to help you best determine if a YAG is right for your business.