Fiber lasers can cut nearly all common sheet and plate metals used in fabrication. The major groups are carbon steels, stainless and high-alloy steels, aluminum, and reflective nonferrous metals such as copper and brass.
The material affects cutting speed, maximum thickness, assist-gas selection and edge quality, so the same laser power will not have the same capability across every metal.
Carbon steel is the most common fiber laser application and generally offers the greatest maximum cutting thickness. Thin and medium material can be cut with nitrogen-based gases for high speed and a clean edge, while oxygen extends cutting capacity into much thicker plate.
Galvanized and other coated steels can also be laser cut, although the coating can affect piercing, fumes and edge appearance.
Stainless steel is best cut with pure nitrogen to produce a clean, oxide-free edge requiring little or no secondary processing.
Fiber lasers can also process many higher-alloy materials, including nickel-based alloys and titanium. These materials may require different parameters and assist gases, but the same basic melt-and-eject cutting process applies.
Aluminum cuts very well with modern fiber lasers and is commonly processed with nitrogen or compressed air. Because aluminum conducts heat quickly and reflects more laser energy than steel, achievable thickness is generally lower than carbon steel at the same power level.
Higher laser power has significantly expanded the practical thickness range for aluminum.
Modern fiber lasers can also cut highly reflective materials such as copper and brass. These materials were historically more challenging for laser systems, but modern fiber sources and cutting heads are designed to handle reflected energy much more effectively.
Maximum thickness is generally less than steel, but fiber laser is well suited to many sheet-metal applications involving copper, brass and similar nonferrous materials.
Material type matters just as much as laser power when determining cutting capability. A laser capable of cutting very thick carbon steel will not necessarily cut the same thickness of stainless, aluminum or copper.
Author: Alex Burnham, Senior Product Manager, Fairmont Machinery
Technical Review: Chip Burnham, Owner & CEO, Fairmont Machinery
Last updated: October 2026
