Metal laser marking (1) – Elena
This section presents information that ranges from the principles of metal marking and processing to the advantages, grouped by the laser wavelength.
It presents examples of marking and optimal laser markers for a variety of materials such as aluminum, stainless steel, iron, copper, cemented carbide and gold plating.
Types of metal marking
Black annealed marking (oxidation)
When the laser beam is applied to the object to be marked, the focus shifts so that only heat is conducted. When applying heat, without producing an engraving on the object, on the surface will forms an oxide film. This film is black and represents black marking.
White engraving
Applies a laser beam to the object to be marked at the focal point. Slightly remove the metal surface in order to expose an irregular surface. This causes an irregular reflection of the light to create a white marking.
Deep engraving
The laser light radiates the focal point and etches the surface of the object to mark it. A deeply recorded impression can be achieved, increasing the engraving volume by increasing the laser irradiation count.
Surface peeling
It uses laser irradiation to unclog the surface, removing the galvanic layer of the object to mark it. This makes the substrate visible, which makes the marking appreciated.
Types of metal processing
Laser cut
Concentrate the power of the laser light with a laser oscillator, and focus a fixed point of the object from the irradiation unit to melt it. Because there is no contact, it does not cause a reaction with the processed item. Keep the deformation and fissures in minimum. In addition, since it is possible to specify processing areas with great precision, it is possible to create holes or cuts located in places where cutting tools do not fit.
Welding barrier
Due to the trend towards smaller and thinner products, some connector terminals have welding barriers (nickel barriers) to control its absorption. Conventionally, using masking in places where electroplating was not necessary, but removing the material from the mask took time and effort. In these cases, the surface peeling with laser light is effective.
Welding
Laser welding is a method that radiates laser light on metal objects, and joins them at one point, when melted and solidified. It is possible to radiate a point with high density energy and complete the process at high speeds. Can keep material distortion in a minimum due to heat. In the past, deformations easily occurred. Now we can weld even very thin materials.
Soft welding
The heat of the laser melts the solder paste that bonds to the metal.
Irradiation of localized laser points is possible, so it is suitable for small parts. In addition, in comparison with the flow method in which heat is added to the entire piece, the load caused by the effect of heat on the piece can be reduced.
See more in the next blog.