Plastic engraving, also known as laser marking of plastic, is a technique in which objects are engraved or imprinted with the use of a laser. Lasit laser marking is a procedure in which the laser beam must be absorbed by the plastic. The polymer utilized to make the plastic pieces dictates the procedures used as well as the amount of energy required to laser the plastic.
Process of Laser Marking
The secret to laser marking plastics is obtaining adequate laser beam absorption into the substance. In metals, most of the beam is reflected, while in plastics, diffuse reflection, transmission, and absorption are more important. Because of the poor heat conductivity of plastics, there are minimal energy losses during plastic marking. As a result, plastics can be marked much faster than metals.
Plastics’ macromolecular structure typically absorbs in the ultraviolet and far-infrared ranges. Absorption occurs at various wavelength spectrums in additives such as carbon black or dyes. Because multiple wavelengths of lasers are accessible, the wavelength can be adjusted for the specific material.
Methods Used in Laser Marking
Foaming
The foaming process creates a visible trace on the plastic. It is possible to think of it as laser-induced boiling, which dissolves the surface. Bubbles are enclosed in the material as a result of the quick cooling. These bubbles give a visible uplifting effect.
The laser operates at a modest power level and with longer pulses. Foaming is effective on all polymers, as well as some metals. Depending on the substance, the mark might be dark or light.
Carbonizing
On bright items, carbonising provides for stark contrasts. In the carbonizing process, the laser heats the material’s surface and emits hydrogen, oxygen, or a mixture of these two gases. What remains is a darkening region with a higher concentration of carbon.
Changing in Color
The material’s color change ensures maximum clarity. Laser color change marking is essentially an electrical method that reorders macromolecules by altering their orientation. The color change is possible with all polymers, and the color shift might be dark or bright. The majority of color shifts are dark.
Removing
Removing is a process that is employed on multilayered plastics. During this process, the laser beam removes the upper layers that had been placed to the base object. As a result of the color variances between the layers, color contrasts appear.
Advantages of Laser Marking on Plastics
Laser marking is becoming increasingly popular in industrial applications since it is regarded as highly reliable and offers several benefits. Its application can be of high grade as well. It is suitable for permanent marking since it is waterproof, chemically resistant, wear- and heat-resistant, and lightfast.
It has maximum flexibility custom design in the marking and it’s also appropriate for difficult-to-reach locations. Laser marking is incredibly durable and also impervious to imitation. Because the process is non-contact, there is no wear and tear tool, and there are no consumable costs such as inks, chemicals, and so on. It is easy to handle and there is no need for pre and post-treatment.
Some Key Points for Using Laser Marking Machines
- The laser producing machine is minute, convenient to transport, and has a low volume, allowing it to be utilized on the street
- The operation of laser marking equipment is quite safe, causing no injury to the skin
- Fiber laser source has a long lifespan of 100 000 hours
- The laser marking machine seems to have no consumable parts and comes with a three-year warranty. It can operate for more than ten years without the need for any consumable parts.
- The laser marking machine is simple to use. The marking pace is quick, efficient, and precise.
Types of Plastics Used in Laser Marking
Depending on the laser wavelength, material, and additives employed, short-pulse lasers produce sufficient results with a variety of marking kinds. Some industrial polymers should be mixed with laser-sensitive additives to ensure good clarity and marking quality. The plastics’ characteristics are largely unchanged.
Some Application of Laser Marking on Plastics
Laser marking on plastics has many applications in almost every field. It is very popularly used these days.
- Electric sockets
- Plastic-based housings
- Components of electronics
- Automobile components
- PCBs (printed circuit boards)
- Keyboards
- Buttons and switches that have a day and night design
- Films
- Tools and tool handles
- Sensors
- Packaging
- Animal identification tags
