Stereolithography (SLA) is the first commercialized 3D printing technology, invented by 3D Systems' Co-Founder and Chief Technology Officer Chuck Hull in the 1980s. It uses an ultraviolet laser to precisely cure photopolymer cross-sections, transforming them from liquid to solid. Parts are built directly from CAD data, layer-by-layer into prototypes, investment casting patterns, tools, and end-use parts. Once the SLA printing process is complete, SLA parts are cleaned in a solvent solution to remove any residual uncured resin from the part surface. Cleaned parts are then cured in a UV oven.
SLA is all about precision and accuracy, so it is often used when form, fit, and assembly are critical. The tolerances on SLA parts are typically less than 0.05 mm, and SLA offers the smoothest surface finish of any additive manufacturing process. With the quality SLA can achieve, it is particularly useful for creating highly precise casting patterns (e.g., for injection molding, casting, and vacuum casting) as well as functional prototypes, presentation models, and form and fit testing. SLA technology is extremely versatile and can be used in any number of areas where precision is paramount.
SLA also offers a speed advantage when you require a variety of functional prototypes or quick access to casting patterns. SLA’s winning combination of speed and precision make it an excellent choice for evaluating prototypes. The accuracy of SLA means your prints are faithful to the final design, allowing you to identify and correct design flaws, collisions, and potential mass-manufacturing hurdles before production begins. SLA provides comparable characteristics to parts normally machined from polypropylene or ABS for low- to mid-volume production, and doesn’t require slow, expensive retooling for customization or required tooling changes. SLA also allows for reduced material costs, as any unused resin remains in the vat, ready for future projects.
Because SLA parts can require support structures, they often require post-processing, which opens opportunities for new part characteristics. SLA parts can be vapor honed, or bead or sand blasted, and can even be electroplated with metal, such as nickel. Electroplating makes SLA parts significantly stronger, and also makes parts electrically conductive and more dimensionally stable in moist environments.
SLA materials are available in a wide range of mechanical properties and can produce parts with characteristics similar to injection-molded ABS or polypropylene, suitable for applications such as snap-fit assemblies, automotive styling components, and master patterns, as well as higher-temperature applications and exceptional clarity. SLA materials for higher-temperature applications and clear materials with polycarbonate-like properties are also available. 3D SYSTEMS SLA material portfolio also includes biocompatible materials suitable for a wide range of medical applications such as surgical tools, dental appliances, and hearing aids. Other SLA materials have been specifically formulated for sacrificial investment casting patterns, offering low ash creation and high accuracy, while also being expendable.
By working with our customers over the last 30 years, 3D Systems has supported more than 80 SLA additive manufacturing materials, tuned to application needs. Find the mechanical specifications you need in our existing portfolio, or talk to our experts to find what you’re looking for.
Get the highest productivity possible with the fastest print technology for large and production runs. Quick interchangeable material delivery modules keep machines running to advance your part manufacturing workflow, while 3D Connect™ Service offers proactive and preventative support.
3D Systems has released 21 different SLA printers over the last 3 decades, each providing significant improvements over the previous version, offering you exceptional part quality. Our customers do not have to compromise speed or feature detail because we utilize two laser spot sizes per layer—delivering the best surface finish, small feature definition, and throughput.
SLA 3D printers are able to deliver highly detailed, tiny parts just a few mm in size, all the way up to 1.5 m long parts—all at the same exceptional resolution and accuracy. Even large parts remain highly accurate from end-to-end, with virtually no part shrinkage or warping.
