Top 5 Most Important 3D Printing Technologies & Materials You Need to Know

3D Printing technology is basically the designing and construction of a physical object from digital inputs. It is based on the principle of adding multiple additive layers upon a digital blueprint created in a computer. The design file is sliced into thin layers and sent to the 3D printer. Depending on the printer type, basic materials include plastic, resin, sandstone, rubber, metals, and alloys.

Although considered to be a futuristic concept (like something out of science fiction) its development dates back to 30 years, sometime in the 1980s. The expensive technology was mostly used by industrialists but after 2009, it became globally available to the ordinary consumers.

3D printing technology has a number of pros, such as ease of creating complex designs and prototypes, customization of articles and generation of fewer waste products. On the other hand, significant cons include higher production costs, limited base-material choices and poor strength of crafted items.

Here we have discussed a few cutting-edge 3D printing technologies and printing materials used nowadays.

1. Fused Deposition Modeling

This creates a model creates objects by the layer by heating and melting of thermoplastic filaments. The printer heats thermoplastic and releases the fused material through a nozzle onto a platform in a calculated pattern. A special software calculates how the printer would build each layer and translate physical dimensions into the X, Y, and Z coordinates.  Once a thin layer of plastic is cooled and hardened, the base is lowered to create the next layer. When entire printing is completed support materials are removed, either mechanically or dissolved in detergent solution. Compared to stereolithography the technique is slower.

The CraftBot Plus manufactured by the Hungarian company CraftUnique is a very good design for printing FDM materials like metal or wood-filled PLAs and is perhaps the best cheap 3D printer available.

2. Selective Laser Melting (SLM)/ Powder-based 3D printing

The technique uses 3D CAD data as a basis and forms 3D objects using a high-power laser beam that fuse metallic powder together. Unlike Selective Laser Sintering, the SLM process melts material into a solid 3D object. The fine base metal powder is spread on a plate. Each slice of the 2D layer is fused by laser energy into the plate. The intense energy creates a solid object out of the melted metal. The process continues with completion of each layer.

This process is suitable for applying in complex geometrical prototypes or structures with voids/cavities. It has found extensive usage in aerospace industry and orthopedics. Another great advantage is that it does not need any supporting structure; rather the un-sintered powder acts supporting material.

3. Lost-Wax 3D Printing

This is a combination of 3D printing with traditional metal casting for creating parts with gold, silver, copper, and bronze. The model is 3D printed in wax-like resin along with support structures and the supporting structures are manually removed afterward. One or more sprues will be attached to the model and the model attached to a wax ‘tree’. This tree is placed in a flask and coated in plaster to form a casting mold. The plaster mold is baked in an oven until the wax is entirely burned out. Molten metal is poured into the cavities left by wax and once it is cooled off, the plaster mold is broken and completed metal model removed manually.

In spite of using conventional methods of metal casting to obtain the finished product, the 3D printing tech uses a format of stereolithography and gives a very good commercial output.

4. Stereolithography/ Resin-based 3D Printing

It is the oldest format of 3D printing discovered by Charles Hull back in 1986. A machine called sterelithograph apparatus (SLA) is used to convert liquid plastic into solid 3D objects. The entire process involves the layer-wise building of the 3D model using a computer aid design (CAD) file called STL.

A layer of liquid polymer is spread on a platform which is hardened by a UV-laser ray to create a single layer of the model. The platform is lowered and the next layer is drawn on top of the previous layer. Once the object is complete it is raised by the supporting platform while the excess liquid flows away. The time taken for the process depends on the item produced, which may range from a few hours to several days.

5. Material Jetting

Material Jetting technologies use techniques similar to inkjet printing but instead of ink drops, liquid photopolymer is used. It is spread on a tray and treated with UV rays. As the process gets repeated, thin layers accumulate on the tray to create a solid object. When there are complex shapes that need support, the printer jets a gel-like substance which can be removed after the printing is completed. A staple use in industrial 3D printers, Material Jetting imparts properties such as toughness, transparency or flexibility, with finesse and precision enabling users to create creative and functional prototypes.