Figure 1: Laser Cutting
CO2 lasers with 10.6 micron wavelength are primarily used for cutting non-metal materials. CO2 and fiber lasers are both used for cutting metals; however, as a rule, cutting metals requires substantially higher power levels than non-metal materials. Material thickness and density are important factors to consider when cutting. Cutting through thin material requires less laser energy than cutting the same material in a thicker form. Lower density material typically requires less laser energy, however increasing laser power level generally improves laser cutting speed.
Laser engraving is the removal of material from the top surface down to a specified depth.
Figure 2: Laser Engraving
CO2 lasers with 10.6 micron wavelength are primarily used for material removal to engrave non-metal materials. The material type and laser power level determine the maximum engraving depth and speed of engraving. Typically shallow engraving is a faster process than deep engraving. Additionally, lower density materials engrave faster than higher density materials. Increasing laser power level generally improves laser engraving speed.
For metal engraving, CO2 lasers are not typically used, because most of the laser energy is reflected. However, fiber lasers with 1.06 micron wavelength can be used for shallow engraving into metal.
Marking is the production of human- and/or machine-readable identification or information on a material, such as a barcode, date/lot code, serial number or part number. Other information including logos, diagrams, illustrations and photographs can also be marked on a material.
With laser marking, the laser removes material to create depth (laser depth marking) or modifies the material to change the color, contrast or reflectivity of the surface (laser surface marking). Most materials can be laser marked, but results will vary depending on the laser wavelength used. Both 10.6 micron and 9.3 micron CO2 lasers are used for marking non-metal materials with depth, as well as for surface marking of some metals. Fiber lasers with a 1.06 micron wavelength are used for surface marking of many materials and surface or shallow depth marking of metal. Laser depth marking is sometimes referred to as engraving (see Figure 3 for illustration).
Figure 3: Laser Surface Marking