The SLA technology, i.e., stereolithography, is the basic and oldest 3D printing method, developed in 1984. Due to the significant technological progress and development of LFS (Low Force Stereolithography), the technology is still widely used in almost all industries, despite being invented in the 1980s. SLA is now one of the most money-saving manufacturing technologies, which additionally contributes to its unflagging popularity.
What is SLA/LFS 3D printing?
Stereolithography is a 3D printing method based on the manufacturing of objects by selective sintering of liquid engineering material in the form of resins. At the beginning of the manufacturing process, liquid resin is poured into a special tank called a cuvette. A printer build plate is placed there, considering the appropriate distance from the liquid surface. At the next stage of manufacturing, the laser beam focused on the precalculated path and the generated contour of the object begins the process of polymerization (curing) of the resin layers. After the base layer of material is cured, the build plate rises and the printer scraper blade smooths the layer to remove frequently appearing air bubbles. The whole action is repeated until the intended object form is achieved. It should be noted that the object manufactured in the first cycle is still not fully cured and requires post-curing, which significantly improves the thermal and mechanical properties of the object manufactured.
Materials used in stereolithography
Along with the development of the technology itself, the selection of available materials used in SLA/LFS printing has also increased. The basic building materials used in stereolithography are various types of liquid photopolymer resins. Among the materials there are standard, highly durable, dental, and rubber-like resins. The materials differ in their properties, which additionally emphasizes the versatility of the technology.
Standard resins are a universal choice for prototyping and manufacturing end-use parts. Highly durable resins are used to manufacture models with the highest mechanical resistance, very often required in the industry. Dental resins have good abrasion resistance and biocompatibility, due to which they can be used, among other applications, for the manufacturing of dental implants. In turn, rubber-like resins are distinguished by its specific properties similar in nature to those of rubber.
Applications of SLA/LFS 3D printing
The objects manufactured with the SLA/LFS technology are highly durable and possess all the properties of the material used. Due to the above, it is possible to predict the behavior of products used in different conditions, including situations unfavorable to materials of other types, such as contact with water or other liquids. High precision, print speed, and quality of the objects manufactured with the SLA/LFS technology make the method perfect for demanding production scenarios in the automotive, healthcare, and jewelry sectors. The most frequently manufactured objects include, among others, prototype models, prostheses, precision casting molds, and various electronic components.
Advantages of SLA/LFS
The main advantage of the SLA/LFS technology is the possibility to manufacture objects of an advanced shape, including transparent elements, and the possibility to reproduce precise details with dimensions of up to several microns. The wide selection of the materials available, both flexible and rigid, further emphasizes the high versatility of the SLA/LFS technology. The obvious advantages of SLA/LFS also include reliability, high production profitability, and the possibility of simple post-processing.
