Fine Laser Cutting: Definition & Capabilities AMADA WELD TECH Lately, we’ve been doing a lot of talking about laser cutting. Fine laser cutting, that is. But what, exactly, is ‘fine’ laser cutting? Fine laser cutting applies to the cutting of metals, such as 300 and 400 series stainless steel, aluminum, nickel, titanium, nitinol and copper less than 0.04” (1.0mm) thick. In fact, they can be very thin – 0.0005”-0.002” (10-50 microns) – as the laser imparts no physical force on the part during the process. In addition to the thickness of the part, fine cutting is also defined by cut feature tolerances which can be down to ± 0.0005”. Got that? OK! Let’s consider a few examples that highlight fine cutting – Medical Tube; Cannula Material 304 Stainless steel Thickness 0.004” Smallest dimensional tolerance ±0.0005” Average laser power 25W Edge quality requirements Burr < 0.0005” Average cutting speed 0.06”/s Battery Jelly Roll Material Copper (anode) Aluminum (cathode) Thickness 0.0005” metal, 0.008” active layer Smallest dimensional tolerance ± 0.015” Average laser power 50W Edge quality requirements Heated affect zone < 0.001” Average cutting speed 5”/s Medical Bone Saw Material 301 full hard stainless steel Thickness 0.05” Smallest dimensional tolerance ± 0.002” Average laser power 375W Average cutting speed 0.1”/s Edge quality requirements Burr < 0.0005” Light housings Material Aluminum 1050 Thickness 0.01” Smallest dimensional tolerance ±0.015” Average laser power 400W Edge quality requirements Burr < 0.0005” Average cutting speed 1”/s So now that you understand the process, let’s talk about equipment. Just what do you use to achieve fine cutting? Fiber lasers are preferred for this type of cutting as they offer focused spot sizes down to 15 microns for the highest cut resolution, and excellent control and stability of laser power. Typical power levels range from 20-500W, and, in the majority of cases, the laser is not used in the continuously on mode as the parts are not sufficiently thick or features sufficiently large to allow it to dissipate that quantity of laser power. Rather, the laser is used in pulse mode, and with pulse widths down to 10 microseconds and pulse frequencies up to 50 kHz, the fiber laser has the necessary tools to produce an optimized cut for both speed and quality. The motion system is also a key part of the equation particularly for acceleration and deceleration rates; features sizes are so small that rarely is a system at constant speed for more than a fraction of a second. In most cases linear and direct drive stages are used. Category: Laser Cutting
