威廉希尔官方下载Feb 24, 2020
The continuous advancement of fiber laser technology and their integration into compact, space-saving beam delivery systems are enabling polymer marking and welding to find wider applications in the medical equipment field. Medical equipment manufacturers consider the footprint of laser marking and laser welding systems when adopting next-generation laser processes in their manufacturing plants, or when upgrading or replacing existing laser processing processes. Because many medical devices are produced in cleanroom plants, compared to traditional manufacturing plants, cleanroom construction and maintenance are relatively expensive, so saving space is very important.
Medical device manufacturers are increasingly evaluating and deploying 355nm pulsed ultraviolet (UV) fiber lasers for a wide range of polymer markings; they are also using 2μm continuous wave (CW) erbium-doped fiber lasers for transparency Welding applications between polymers and transparent polymers, and between certain polymers and metals.
Laser marking of polymers
Traditional polymer marking mainly uses infrared (IR) lasers, or near-infrared (1 μm) lasers, or far-infrared (LWIR; 10 μm) lasers. Due to the relatively low cost and high reliability, these types of lasers (including 1 μm fiber lasers and diode-pumped solid-state lasers and 10 μm CO2 lasers) are generally processed by a thermochemical laser process called carbonization. Produces black or gray marks on the material. The carbonized laser marking process usually generates a large amount of laser smoke and other debris, and a good laser smoke extraction device needs to be designed to produce an acceptable marking effect. This marking method usually requires a subsequent cleaning process to remove soot particles adhering to the polymer surface.
CO2 lasers are also often used in different laser marking processes. This process is often referred to as the laser blistering effect, which forms raised marks on hard plastic. In this process, the laser beam heats the surface of the material and generates air bubbles in the material being heated near the surface, thereby forming a raised and cured optical mark that forms a good contrast with the surrounding unmarked material. This long-wavelength thermal laser marking process is widely used in various industrial productions such as consumer electronics equipment, automotive parts, and packaging.
Compared to traditional infrared polymer marking processes, polymer UV laser marking is a photochemical marking process that depends on the higher photons of these UV lasers than traditional near-infrared and far-infrared marking lasers. energy. The incident focused UV laser will be absorbed by the material in a depth region very close to the surface, which can produce high contrast marks in an efficient "cold" marking process. One of the great advantages of this "cold" marking process is that it forms intuitive characters and patterns with minimal discoloration of adjacent areas or minimal heat-affected areas. Such marks are generally formed under the surface, and the processing does not have any effect on the finish and / or external aesthetics of the part.
In the late 1990s, the development of triple-frequency Q-switched diode-pumped neodymium lasers using lithium triborate (LBO) as a frequency-doubling crystal further promoted the increase in UV marking applications for polymer materials, and UV lasers began to replace Excimer lasers and infrared lasers in the polymer marking market. UV lasers demonstrate their ability to mark on a wide range of polymers without additives, including polycarbonate (PC), acrylonitrile-butadiene-styrene copolymer (ABS), Silicone resin, high-density polyethylene (HDPE), polyetheretherketone (PEEK).
UV laser marking of polymer medical devices
Recent rapid advances in fiber laser technology have achieved highly reliable pulsed UV fiber lasers. They have a very compact structure and can provide suitable single pulses at high pulse repetition rates (> 100kHz) and short nanosecond pulse widths. Energy is used for the efficient marking of polymers. The well-known advantages of pulsed fiber lasers include excellent reliability and lower overall operating costs, which makes it possible to replace traditional lamp- and diode-pumped Q-switched solid-state lasers in many market segments. These advantages are now driving the rapid adoption of fiber lasers in UV laser marking machines, including polymer marking for the medical device market. Combining a pulsed UV fiber laser with a galvanometer scanning system with a UV f-theta scanning mirror to form an easy-to-operate UV laser marking system provides medical device manufacturers with an attractive solution for their production facilities A compact marking system that can be used at any time.
The advancement of fiber laser technology continues to promote the emergence of new applications and promotes the development of new applications and beam transmission technologies in this market area.