Although lasers are versatile, there are instances when waterjet or plasma is a better option. Lasers are negatively affected by a number of factors including material thickness and quality, alloy type, heat conductivity, metallurgy, and even part geometry. Waterjet is better in some cases simply because it does not emit the high temperatures associated with lasers. Conversely, plasma or oxy-fuel is a better choice for thick parts where edge quality and taper are less important.
Today, many OEMs are introducing higher power lasers to help address thick cutting issues. For example, Mitsubishi now offers their fiber lasers in 4, 6 and 8-kW iterations with patented ZOOM head cutting technology. The ZOOM head is capable of manipulating not just the focal length, but also the SHAPE of the mode. In essence, the ZOOM head can transform the Beam Product Parameter (mode) from looking like a TEM00 mode on a CO2 laser to looking like a CO2 TEM01 mode. The results are smaller, conical shaped mode for fast thin material cutting and doughnut shaped mode for better edge quality in thicker plate cutting. It’s like having the best of both worlds.
With various power levels and technologies available, it’s key during the due diligence phase of a new fiber laser purchase to research and understand the differences and features of the cutting head when considering resonator wattage. When choosing a fiber machine, a cutting head capable of manipulating the beam product parameter is ideal.