The RP techniques currently available in the industry are described next. These includes,
Some of these processes are explained as below with their relative advantages and disadvantages.
- This is based on selective polymerization of a photosensitive resin using ultraviolet light.
- In this system, an ultraviolet laser beam is focused on the top layer of photo sensitive resin contained in a vat.
The beam is positions and moved in horizontal X and Y directions to polymerize the resin within the boundary a particular cross-section.
The cured layer of polymer is lowered by a platform attached to it, so that a fresh layer of liquid resin covers the cured layer.
- In this process a high power laser beam selectively melts and fuses powdered material spread on a layer.
- The powder is metered in precise amounts and is spread by a counter-rotating roller on the table.
- A laser beam is used to fuse the powder within the section boundary through a cross-hatching motion.
The table is lowered through a distance corresponding to the layer thickness (usually 0.01 mm) before the roller spreads the next layer of powder on the previously built layer.
- The unsintered powder serves as the support for overhanging portions, if any in the subsequent layers.