YAG lasers have been used extensively in micromachining metals and ceramics. Systems usually utilize fixed laser beam with short focal length (50mm to 80mm) lens mounted inside assist gas nozzle. Typically, nozzle has close loop autofocus feature that allows to maintain constant gap between the lens and material to maintain consistent kerf of laser cut. For most applications, using oxygen as assist gas will allow achieving acceptable cut edge quality. For cutting special alloys like Nitinol or MP35N argon can be used to prevent oxide film formation on the edges of the cut.
Many metals like gold, aluminum, copper have high reflection coefficient for fundamental frequency of YAG laser. In this case, Double Frequency YAG lasers (wavelength 0.53um) will provide cutting solution. Shorter wavelength allows to achieve same power density at less power, which results in smaller heat affected zone (HAZ). This wavelength also allows cutting many types of plastic without unwanted edge melting. Typical system includes high precision mechanical stages and galvanometer head to achieve fast cycle time and batch processing. With software combining mechanical and galvanometer system we can achieve a so called infinite field of view (IFV) to laser cut features over large area of the part.
We use our Triple Frequency YAG lasers if your project demands micromachining material with minimal amount of induced heat. This system is used for laser cutting most plastic materials including multilayer laminates, adhesive films, thin ceramic parts and materials with high surface stress. Also, because of shorter wavelength 0. 35um, laser beam can be focused to a smaller spot size with reasonable depth of focus for laser holes drilling. Laser systems are configured similarly to Double Frequency YAG systems. Ultimately, your specific application drives our laser selection decision.