These 0.125 high characters were marked using an air-cooled t60 laser with a FH marking head and 80mm lens. The marks were made at a speed of 0.5/s using 60W, the 18 character mark has a cycle time of 4.8s. An interesting result of marking carbon steels with a CO2 laser is the rust resistant nature of the marks. The mark behaves similar to hot rolled steel when exposed to an oxidizing environment. This marking characteristic would be especially useful in producing durable part number marks on suspension and exhaust parts.
These 0.125" high characters were marked on a steel automotive part using 60W.