Experiment on Applying a Color Image to AISI 304 Stainless Steel With a Fiber Laser (Endurance 30 Watt Raycus + Sino-Galvo SG7110).

A task:

Create a color image on a stainless steel surface without the use of dyes. This work uses the so-called "tarnish effect" - the property of metals to change their color when heated. Similar ideas are presented at https://endurancelasers.com/engraving-on-metal/

We fix the stainless steel plate (hereinafter referred to as the workpiece) on a mechanical lift. Using the adjusting knob, set the lift height to 74 mm. (this will place the workpiece 3 mm above the focal point) Here you can learn more about the laser installation on which the work was carried out: https://endurancelasers.com/diode-lasers/endurance-coherent-fap800-laser-model-15-watt-25-watt-30-watt-808-nm-wavelength/

The drawing of a flower was taken as a basis. Next, the image was divided into layers (one layer for each color)

In the EzCad program, we engrave each layer in a certain mode:

Orange: speed 250 mm / s, power 60%, frequency 20 KHz, number of repetitions

Green: speed 350 mm / s, power 75%, frequency 20 KHz, number of repetitions

Purple: speed 300 mm / s, power 70%, frequency 20 KHz, number of repetitions

Red-violet: speed 450 mm / s, power 70%, frequency 20 KHz, number of repetitions

Turquoise: speed 400 mm / s, power 70%, frequency 50 KHz, number of repetitions

White: speed 250 mm / s, power 40%, frequency 50 KHz, number of repetitions

Each layer should be applied separately. In no case should the workpiece be moved, otherwise the layers will shift or overlap. Also, do not change the height of the lift, otherwise the resulting color will become unpredictable.

After engraving a metal plate in the specified modes, a clear color image was obtained. It should be noted that some colors are not uniformly applied. This effect was a consequence of the small size of the image and the uneven heating of the metal surface.