3d Printing Process
The Z Corp rapid prototyping process creates affordable, fast prototypes in color. The 3D parts created with this process are excellent for visual aids and concept models, especially ones with complex shapes. The range of industries using the Z Corp prototyping process including automotive, architecture, footwear, sculpture, consumer products, consumer electronics, packaging and education. Any prototype where color and speed are important are well served by this rapid prototyping method. The drawback to the technology is that the surface finish, accuracy and strength are not as good as with other 3D rapid prototyping methods.
How Z-Corp Works
Z Corp uses an ink-jet based process that prints the 3D part’s cross sectional geometry on layers of powder spread on top of each other. Powder is first spread over the surface of the ‘build piston.’ Using the inkjet print head, the Z Corp printer sprays a binding solution onto the powder in the shape of the first cross section of the CAD model. The build piston lowers one layer and more powder is spread using the spreading apparatus.
Layer by layer these sections are bonded together until the process is complete. After the binder has been allowed to sufficiently, the part is removed from the printer and excess powder is blown off of the part. Any excess powder is easily removed at the completion of the build, allowing for intricate shapes to be built without the need to remove any support material at the end of the build process. Finally, the part can be finished using infiltrants including wax, cyanoacrylate (super glue) and epoxy materials, which will increase the 3D parts strength and create the desired finish.
Z Corp. 3D printers use standard inkjet printing technology to create parts layer-by-layer by depositing a liquid binder onto thin layers of powder. Instead of feeding paper under the print heads like a 2D printer, a 3D printer moves the print heads over a bed of powder upon which it prints the cross-sectional data from the CAD file which has been sliced into appropriate build layers.
The Z Corp. system requires powder to be distributed accurately and evenly across the build platform. 3D printers accomplish this task by using a feed piston and platform, which rises incrementally for each layer. A roller mechanism spreads powder fed from the feed piston onto the build platform; intentionally spreading approximately 30 percent of extra powder per layer to ensure a full layer of densely packed powder on the build platform. The excess powder falls down an overflow chute, into a container for reuse in the next build. Once the layer of powder is spread, the inkjet print heads print the cross-sectional area for the first, or bottom slice of the part onto the smooth layer of powder, binding the powder together. A piston then lowers the build platform 0.1016mm (0.004″), and a new layer of powder is spread on top. The print heads apply the data for the next cross section onto the new layer, which binds itself to the previous layer. This process is repeated for all of the layers of the part. The 3D printing process creates an exact physical model of the geometry represented by 3D data. Process time depends on the height of the part or parts being built.
Typically, Z Corp.’s 3D printers build at a vertical rate of 25mm – 50mm (1" 50mm 2") per hour. When the 3D printing process completes, loose powder surrounds and supports the part in the build chamber. The part is then removed from the build chamber after the materials have had time to set.
Forced air is then used to blow the excess powder off the printed part. Z Corp. technology does not require the use of solid or attached supports during the printing process.