Laser cutting machine manufacturers have
analyzed that in general, there are a variety of materials that can be laser marked. Metal, plastic, ceramic and even organic materials can be laser marked. Whether they can be marked depends on the material's absorption of the incident laser. Happening. There are many types of lasers that can be used for laser marking, including gas lasers (CO2 lasers) with a wavelength of 10.6 μm; Nd: YAG and Nd: YVO4 solid-state lasers with a wavelength of 1.06 μm, Yb-doped fiber lasers; frequency-doubled YAG and YVO4 solid-state lasers; wavelengths Excimer lasers in the visible and ultraviolet bands. Different materials have different absorption bands for laser light. Metal has a high reflectivity for a laser with a wavelength of 10.6 μm, so it is best to use a laser with a wavelength of 1.06 μm for marking metal materials. In contrast, glass is transparent to light with a wavelength of 1.06 μm, so A laser with a wavelength of 10.6 μm or a laser in the ultraviolet band is preferably used. In addition to the wavelength, there are several key parameters that determine the laser's marking ability. They are: pulse energy, pulse duration, pulse repetition frequency, pulse peak power and average power.
There is a threshold power when the laser interacts with the material. Only when the laser power reaches this threshold, physical processing can begin. The threshold power for laser marking is generally on the order of kW. For highly reflective surfaces or materials that are difficult to process, the peak pulse power needs to be above 10 kW. However, for most material marking applications, a peak power of several kilowatts is sufficient. Another key parameter is the pulse energy, which is typically on the order of mJ. The pulse duration is also a very important characteristic, because it determines the time for thermal interaction with the material, which has a significant impact on the quality of the logo. Generally, the required pulse length is between 10 ~ 200 ns. Pulse frequency refers to the number of pulses per second (unit is Hz). The working frequency range of a typical laser marking system is 20 ~ 80 kHz. The average power is determined by the pulse energy and pulse frequency, and the average power value represents the total energy that the laser can provide.
Today, almost all products carry some form of identification, including the barcode, product serial number, company logo, and production date. In addition to helping consumers understand product information, product identification also plays a very important role in preventing manufacturers from counterfeiting and creating brand effects. Therefore, manufacturers now pay more and more attention to product identification, and even traditionally do not need naked identification. Products such as eggs and apples have also appeared with marked products. Laser marking has become a commonly used technique for product identification, and its application is becoming more and more widespread. With the improvement of laser marking machine
performance and price decline, laser marking has also gradually moved from the previous external processing methods to manufacturers own laser marking machines
. In the next few years, laser marking machines
will face rapid market expansion. opportunity. Laser marking technology has a history of more than 20 years, and has now steadily occupied a part of the market that was once dominated by traditional marking technologies such as EDM, corrosion, mechanical scoring, and inkjet printing. There are two main reasons why laser marking can gradually replace inkjet printing. One is that the inks, pigments and solvents used in inkjet printing will cause environmental problems. On the other hand, the durability of inkjet printing is also problematic. Most tags can be removed using solvents. In contrast, laser marking produces sharp, durable marks on a variety of materials. Therefore, in recent years, laser marking has gradually been favored by users, and the application range has become wider and wider.