Laser glass processing is making its way
New laser glass processing technologies that offer fast and accurate production, have become an attractive alternative to conventional methods such as mechanical breaking, use of a diamond saw or water jet cutting. Laser technologies are being developed today ensure high quality and reliability.
Glass is a unique material. We usually associate it with a brittle material, but not everyone knows that glass can be more transparent than air and stronger than steel. With the application of better glass processing technologies, this material is used everywhere – in medicine, electronics, engineering, architecture, etc. Discovering new uses for glass poses new challenges for glass cutting or other processing. Only the selection of the exact cutting process can guarantee the desired glass size and shape. One of them is laser cutting. Showing good results, this technology is receiving more and more attention in scientific laboratories and industry. With the emergence of a wider range of parameters for lasers and laser systems, their application in the processing of glass and other materials is gaining new momentum.
Traditional glass processing tools
To date, the most commonly used glass processing technologies in industry are high-pressure water jet cutting, diamond blade cutting, and more. One of the oldest glass cutting technologies is diamond blade cutting, which does not require much preparation or expensive equipment. Nevertheless, the method limits the variety of shapes to be cut, the quality of the cuts is highly dependent on the mechanical force used, and the edges are often characterized by macro-cracks. As an alternative, a diamond blade is used in industry for simple and fast straight-line glass cutting.
In industry, we can often find another method – the use of high-pressure water jets. During it, a stream of high-pressure water is focused on the incision point. The advantage of this method is that the workpiece is not exposed to heat during cutting. As a result, heat-induced deformations do not occur at the cut edges, and no new stresses are caused in the cutting area compared to mechanical cutting. The high-pressure water jet also allows the processing of multilayer materials.
Although these technologies are well-established and offer fast processing at a low cost, they do not meet the growing demand for the production of complex, miniature and high-quality-demanding parts.
Constantly improving laser processing
Laser cutting is a very attractive tool due to the precise and limited deposition of energy in the material, both in space and time. It ensures high processing accuracy and low damage to the surrounding material. The infrared (IR) laser beam generated by the CO2 laser is most commonly used to cut glass. This technology is widely used in design and other fields where the need for small quantities of glass products predominates. Meanwhile, UV lasers predominate in mass production, where large-scale industrial glass processing is required (microelectronics, telephone glasses, etc.).
Laser cutting systems not only get a clean incision fracture, but also shorten the cutting process time. It is a non-contact and clean process of material processing that usually requires no additional processing. The whole cutting process can be controlled by a computer, which makes it possible to extract forms of varying complexity. With the development of modern industrial lasers, laser technology can provide high performance.
Compared to other glass processing technologies, the laser beam can be focused on a smaller area. This allows for much more accurate and complex cuts. Laser glass processing allows to obtain very narrow cuts – up to 0.3 mm. For example, high-pressure water flow up to 0.9 mm, plasma cutting – 3.8 mm cutting width track.
LITEK™ cluster develops innovations in laser processing
Researchers of Department of Laser Technologies (LTS) of Center for Physical Sciences and Technology (FTMC) which is a member of LITEK™, led by dr. Gediminas Račiukaitis, constantly performs glass cutting experiments using laser technologies and surprises the world scientific community with his discoveries. The publication of the FTMC LTS research group, published in the journal Optics Express (OSA Publishing) in October: “In-depth comparison of conventional glass cutting technologies with laser-based methods by volumetric scribing using Bessel beam and rear-side machining” – became one of the the most downloaded article of the day by OSA Publishing.
Researchers have proven the advantage of laser technology over mechanical glass cutting and cutting of this material using water jets. “Laser engraving and refraction allows to reach better surface quality. It is also more flexible as it allows cutting high-radius contours compared to mechanical engraving. An even more flexible technology is processing from the underside of the glass sample. In this way, free-form contours can be cut or complex 2.5D structures can be milled, for example to make micrometric gas nozzles. Both of the presented laser methods are superior in terms of quality than water jet cutting, which is widely used in industry “- says dr. Paulius Gečys, FTMC LTS researcher.
JSC ELAS, a member of LITEK™ cluster, that constantly invests in R&D and cooperates with FTMC LTS scientists, develops and manufactures high-tech laser micro machining workstations used in scientific institutions and industrial enterprises.In the newly developed micro machining workstations are integrated the latest laser systems with high-precision processing of transparencies (including glass) and other materials. According to Saulius Mikalauskas, the director of JSC ELAS, the interest in processing of transparent materials is steadily growing every year, together with the laser material processing segment itself. “As specialists in this field, we receive a lot of inquiries,” -he says.