Another interesting thing is that it is possible to create a color image. For this purpose, we have equipment designed to generate emission with the required wavelength and energy, which is converted into color on the metal. Equipped with a scanning system, the equipment forms the desired pattern with high accuracy.
Color reproduction
The depth and hue of the color depends on a list of factors:
- the type and thickness of the metal;
- power and properties of the surface oxidized layer;
- thermal properties of the material;
- characteristics of the laser pulse output – power, frequency.
By selecting the parameters, the operator of the engraving machine determines the technical possibilities of formation of transitions, their coloring gradients, finished colors and their saturation.
At the same time with the target colors in engraving can be formed blueing: a peculiar result of local physico-chemical transformations in the form of a fresh film of oxide compounds. This looks like an area painted in overlapping colors.
Laser imaging is allowed for stainless steels, titanium, nickel-plated surfaces, brass, zirconium – all those that are prone to oxidation.
The technology of engraving consists in spot focusing of laser beam – it does not bring energy to surrounding layers of material (similar to welding arc), as a result of which only irradiated spot changes its color. We use a fiber laser: it provides color engraving with minimal energy loss.