Laser ablating busbars
Busbars are made of metal, typically copper or aluminium, and are used in electric vehicles for power distribution and to connect high or low voltage equipment in battery banks. They conduct a large amount of electricity and have an epoxy coating for insulation. This coating must be partially removed so that the busbars can electrically connect to other components in the vehicle.
Unlike mechanical methods, laser ablation is contactless, without ablation or loss of metal, and with very little downtime or tooling needed for any changes. A galvanometer scanner passes the laser beam over the required area, turning the busbar midway through to process all sides, while leaving the metal undamaged. Our CO2 lasers ablate busbar coatings quickly. Removal rates depend on the type and thickness of coating, as well as the coating method (cross layer), but there is no material loss (cost of copper or aluminium) when a CO2 laser is used.
Battery casing ablation
Electric cars are becoming increasingly popular throughout the world with the associated environmental benefits of lower emissions and better air quality. The batteries from these electric vehicles generate heat during recharging, which can shorten the life of the battery. A CO2 laser can selectively ablate the plastic coating of the battery casing; this allows a heat sink to be attached directly to the metal in order to conduct excess heat away from the cell. Depending on the thickness and composition, CO2 lasers can ablate a range of plastics and adhesives in these coatings quickly and cleanly when compared with solvents.
Backlight unit (BLU) patterning
A CO2 laser can be used with an AOM to create a consistent backlighting pattern on PMMA (acrylic) material. The AOM allows the user to control the energy within each pulse when processing in order to give uniform light distribution across the finished piece. The SR AOM laser sources provide precise pulse-to-pulse control along with excellent power stability, and the short rise and fall times minimise heating of the material surrounding the processed area. The result is a highly controllable process, and a pattern of crisp, clean and consistent dots across the entire workpiece.
Cutting & drilling carbon fibre composites
Carbon fibre composites are commonplace in the automotive and aerospace industries due to their high strength-to-weight ratio but machining them is difficult as it evaporates the epoxy resin which binds the composite together. Mechanical processing can result in de-lamination and matrix damage, and tool wear and breakage. Conventional laser processing creates a heat-affected zone (HAZ) around the cut, leaving the fibres exposed and compromising the strength of the material.
With a Luxinar LXR® series ultrashort pulse laser heat diffusion is greatly reduced, so cutting can be accomplished leaving the epoxy resin intact. This means that holes can be drilled and features cut out without compromising the strength of the carbon fibre sheet.
Electric motor hairpin processing
Electric vehicle motors use copper “hairpins”, rectangular copper wires up to 6mm wide coated with a dielectric enamel (PEEK, PFA-PI, PA), to provide electrical isolation; this enamel must be partially removed so that the hairpins can be welded for electrical contacting.
Unlike mechanical methods, laser processing is contactless, without ablation or loss of copper, and with very little downtime or tooling needed for any changes. A galvanometer scanner passes the laser beam over the required area, turning the hairpin midway through to process all sides, while leaving the copper undamaged.
Enamel ablation using our CO2 lasers is a very fast process. Removal rates depend on the type and thickness of coating, as well as the coating method (cross layer), but there is no material loss (cost of copper) when a CO2 laser is used.
Thin film cutting
A wide range of thin films are used in many different industries including display, automotive, EMS, lighting, and flexible packaging. In some cases the film may be mounted on glass, and must be kiss cut without damage to the substrate. In other applications the film is unsupported, and must simply be cut cleanly, with minimal debris and HAZ. An AOM-integrated CO2 laser can bring a higher quality machined finish with less heat affected zone (HAZ) compared to a standard pulsed CO2 laser.
Luxinar’s SR AOM has a typical 2μs demand pulse shape that exhibits a ~350ns pulse rise time. This short rise/fall time helps to minimise HAZ which is ideal for cutting thin films such as polarization, projected capacitive and PDLCD.
Laser engraving heat transfers for T-shirts
CO2 laser technology finds a host of innovative applications across the fashion industry.
For example, CO2 laser cutting machines can create designs on heat transfer films that are used to decorate T-shirts and other fabric garments. In this case the laser doesn’t cut the clothing. Instead, the laser engraves a type of laser-friendly transfer film, removing excess material and leaving only the required design intact. The design is then transferred to the garment using a heat transfer press. Fully engraving the film has the advantage that the transfer does not require “weeding” before use – this is the time-consuming process of removing small pieces of waste material from the design, which would be left by simply cutting the profile out. With an engraving process, all of the waste is removed by the laser, reducing the total process time significantly.
Our CO2 lasers can be used to mark a wide range of plastic products, from packaging films and bottles to medical devices. The appearance of the mark depends strongly on the type of plastic used.
In many cases, the laser induces no colour change in the plastic, resulting in an engraved mark which is unobtrusive and does not spoil the appearance of the product. Special additives can be used when a more visible mark with high contrast is required. This also happens with many pearlised plastics, as well as PVC.
Plastics are widely used in the world today – applications include automotive parts, signage, medical devices, packaging, lighting, white goods, furniture, electronic devices, and many more.
CO2 laser cutting of plastics is a very efficient process; high absorption and low thermal conductivity means that little energy is wasted. However, plastics are a diverse group of materials, and the results depend strongly on the type and chemical composition of the plastic in question.
Thermoplastic materials can generally be cut cleanly – these include acrylic, polyethylene, polystyrene, polypropylene, PET, polyurethane and ABS. Thermosetting materials such as epoxy and phenolic resins and polyimide are difficult to cut without discolouration or charring, on the other hand.