Laser Cutting Alloy SteelAlloy steel is a name applied to a range of alloys with different characteristics depending on the specific alloy. The alloy steels most frequently encountered are Ni steel, Cr-Mo and Cr-Mo-V steels, and some high strength alloys containing Cr, Ni, Mo and other elements. Alloy steels frequently need to be cut to size or shape. Lasers can be used to cut alloy steels, and are gradually finding application in more industries. While CO2 lasers are normally used for cutting steel, a YAG laser can also be used. The cutting gas is often oxygen as this enables fast cutting speeds to be used. Most applications involve cutting of material up to about 4mm thick, but high power lasers are capable of cutting plate up to about 20mm thick. The surface of the steel in the area of the cut needs to be clean and free from rust and oxide. Lasers give good, clean, accurate cuts, free from dross and only produce a narrow HAZ. Some alloy steels have high hardenability and are liable to crack unless preheat is applied prior to cutting. The process is useful for industries using thin materials to provide components with close dimensional tolerances giving good fit-up keeping fabrication costs down. The main safety issues are electrical and radiation associated with use of lasers.
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