Nowadays femtosecond lasers are being considered for a growing list of micromachining applications with their ability to process any material with a minimal amount of heat-affected zones (HAZ). This type of ultrafast lasers is an ideal technology not only for micromachining, but also for medical device fabrication, scientific research, eye surgery, and bioimaging. Short pulse durations, along with higher energies and lower costs, are helping femtosecond lasers produce the next generation of medical implants, make smartphone glass covers more durable and improve the fuel efficiency of automobiles through the drilling of gasoline injector nozzles. The short pulse duration of femtosecond lasers enables material processing with cold ablation. Plus the optional second harmonic allows smaller features or higher ablation rates.
Currently, femtosecond lasers and laser systems have become popular tools for machining transparent, brittle materials, as the ability of cold ablation promises process results with the minimum amount of chipping and micro-cracks. Application of femtosecond lasers can result in high cut quality. The very high cutting quality also leads to extremely high bending strength. In addition to this, the high peak intensity of femtosecond lasers enables nonlinear absorption inside of transparent materials. The availability of femtosecond lasers with more than 100 μJ pulse energy and special multi-foci optics now enable simultaneous modification of four layers, resulting in four-times-faster cutting speeds.
High precision and excellent process quality are ideal for drilling gasoline injector nozzles. Automakers around the world are under pressure to meet increasingly strongest mileage requirements, so they are working on at least two fronts:
- to design drivetrain systems that run on renewable or alternative fuels
- to wring more mileage out of existing fossil-fuel engine designs
The spray pattern depends on the injection pressure, but also on the geometry and sidewall quality of the nozzle holes, so these holes must have very smooth walls post-drilling. Historically, these tiny and high aspect ratio holes with 150- to 250- μm diameters have been drilled by electron discharge machining (EDM). However, femtosecond lasers have now reached levels of reliability and pricing so that they can be dependably used in automotive production. The process of drilling small, high aspect ratio holes with excellent surface quality requires ultrafast lasers with high energy pulses of 80 μJ or more at ultrashort pulse durations. For the drilling of very narrow holes, higher pulse energies at lower repetition rates are more beneficial than higher output powers and higher repetition rates. For drilling holes with aspect ratio, a shorter wavelength, such a second harmonic of a ytterbium laser at around 520 nm, is beneficial. The advantages are a smaller focus spot size and a larger Rayleigh length.
The implementation of the laser drilling process for diesel nozzles is the next development step. Ultrafast lasers with pulse energies >40 μJ at wavelengths in the visible range will be necessary to substitute for conventional EDM methods.
Femtosecond lasers will continue to improve in cost-performance as lasers become even more competitive with mechanical machining methods. Such lasers will provide higher average powers and pulse energies for higher throughput in coming years.
We believe in developing a real sense of partnership with our customers. We are committed to understanding our customer’s needs and providing them with a broad variety of fiber lasers, СО₂ lasers, Ti: Sapphire lasers, dye lasers, and excimer lasers. We offer simple erbium fiber lasers and ytterbium fiber lasers, as well as sophisticated laser systems with unique characteristics, based on the client’s inquiry. We manufacture lasers using our own technologies based on the advanced research work and patents of international R&D team. Laser processes are of high quality, high precision, easily-automated manufacturing solutions that provide repeatability and flexibility.
If you are interested in Optromix femtosecond lasers, please contact us at info@optromix.com