Fully understanding the principle and characteristics of the rapid prototyping technology of model making is the basic requirement of mastering this skill. So, what are the manufacturing methods of rapid prototyping?
At present, the rapid prototyping methods can be divided into the following.
What are the methods of rapid prototyping in model making?
1. UV curing, one of the rapid prototyping methods of SLA, is a common manufacturing method in RP field. The principle is that the liquid photosensitive resin is solidified layer by layer by using ultraviolet laser beam to form a three-dimensional solid. The 3D solid model is designed by CAD, and the model is sliced by discrete program. The data processed by computer software is projected onto the surface of liquid photosensitive resin by laser beam through the scanner of numerical control device according to the designed scanning path, so that a layer of resin in the specific area of the surface is solidified, and a section of the part is generated: after each layer is completed, it is immersed in resin liquid After two-layer scanning, the newly solidified layer is firmly bonded to the previous solidified layer, and this is repeated until a three-dimensional solid prototype is formed.
2. The principle of SLS is similar to that of SLA, except that the liquid photosensitive resin is replaced by various solid sintered powders (metal, ceramic, resin powder, etc.) which can be sintered under laser irradiation. The basic process is that the laser beam controlled by CAD software is projected onto the working face covered with a layer of sintered powder, and the powder layer is scanned point by point according to the section information of the part. The powder layer irradiated by laser is melted and sintered, so that the powder particles are bonded to form the solid part of the part. Every time a layer of sintering is completed, the working platform is lowered one layer, the working surface is covered with a layer of powder again, and then another layer of sintering is carried out, so as to form three-dimensional parts layer by layer.
3. FDM method: the method uses filamentous materials (paraffin, metal, plastic, low melting point alloy wire) as raw materials, and uses electric heating method to heat the wire in the nozzle to slightly higher than the melting temperature. Under the control of the computer, the nozzle scans the X-Y plane, shoots the molten material from the nozzle at the feeding port, and coats it on the worktable. After cooling, a layer of cross-section of the workpiece is formed. After one layer is formed, the nozzle moves up one layer to coat the next layer. In this way, the three-dimensional solid is formed layer by layer.
4. Layered solid forming LOM method, also known as laminated forming method, is based on thin sheets (such as paper, plastic film or composite materials) as raw materials, which are laminated and laser cut to form a model. The principle is that according to the cross-sectional profile data extracted by computer, the laser cutting system cuts out the inner and outer contour of the model from the sheet coated with hot melt adhesive on the back; after cutting one layer, the worktable descends one layer, and a new layer of sheet is superimposed on the newly formed layer, which is bonded together by the hot pressing device, and then cut, so as to bond layer by layer , cut, and then become a 3D solid.