3D printers are available in both hobbyist and commercial grade and able to print materials of varying characteristics, so it helps to have an idea of what you will be making with your printer prior to selecting a substance. Strength, thickness, detail, and price are all factors affecting selection. Will you be prototyping precision parts for an innovative gadget, making toys and jewelry, or perhaps eating utensils? The list of materials is expanding, but includes multiple types of plastics, metals, and ceramics.
Plastics: ABS
The two most commonly used plastics are ABS and PLA. ABS, short for acrylonitrile butadiene styrene, is petroleum based and comes in a spaghetti-like filament and is available in multiple colors. ABS has a minimum wall thickness of one millimeter, with three layers of plastic per that one millimeter printed. The resulting plastic is strong, mildly flexible, and exhibits a high temperature resistance, but it lacks the detail of other plastics on account of the low number of layers printed. Fortunately, ABS is easily sanded and machined to enhance details. The plastic is soluble in Acetone, enabling the easy welding of multiple parts.
LEGOS themselves are printed from ABS .
When working with ABS, maintaining part accuracy is a challenge due to the plastic's slow cooling process. If no external heating source is provided, the plastic has the tendency to curl upwards off the surface in the direction of the 3D printer's nozzle.
Plastics: PLA
Unlike ABS, Polylactic acid is created from corn, potatoes, and sugar-beets.. The plastic is strong, yet less flexible than ABS, making it more difficult to create pin-joints and interlocking assemblies. PLA is available in a large range of colors and translucencies, and exhibits a glossy surface upon drying. PLA cools rapidly and avoids warping, making it ideal for recreating intricate shapes. For this reason, PLA is commonly used for display objects and models.
Metals: Stainless Steel
Stainless-steel resin is often made from layers of steel powder mixed with tiny droplets of glue. Its minimum wall thickness is three millimeters, at approximately six layers per millimeter. The material is strong and rigid with properties similar to 420 stainless steel, but the end result is very fragile, like wet sand, and must be infused with bronze in order to harden. The infusion results in a slight bronze hue coloration.
Metals: Gold and Silver
3D printing gold and silver is much like walking in Mordor, one does not simply do it. The process is three-fold, and ultimately boils down to creating a mold from a wax casting, and filling the mold with the molten metal. Gold and silver permit a smooth high detail surface that can be polished to achieve different textures. The end result is strong and rigid, with a minimum wall thickness of half a millimeter at 10 layers per millimeter.
Metals: Titanium
Titanium is the strongest available 3D printing material, and is shaped using direct metal laser sintering: the process of heating a powder just below its melting point, allowing atoms to diffuse across particle boundaries and solidify. Titanium is very expensive to use, and the process is not feasible for home use. However, the end result is extremely detailed, exhibiting a minimum wall thickness of 0.2 millimeters at about 30 layers per millimeter.
Other: Ceramic
Ceramic powder results in a rigid but delicate print. The minimum wall thickness is three millimeters at approximately six layers per millimeter. The print is low resolution, but smooth and glossy.
Objects printed with ceramic powder must be heated in an oven to harden. Certain design restrictions must be accounted for when designing a model using ceramic powder, as it will warp at different rates inside the kiln. Softer edges are less likely to crack than sharper edges under the high heat.
Other: Gypsum/Sandstone
Gypsum, sometimes called sandstone, is an excellent choice for creating photo-realistic models. The material is printed with high-resolution (650×540 DPI) Z-Corp printers. The printing process simultaneously binds the gypsum using an adhesive while an ink jet head embeds the material. Afterwards, cyanoacrylate sealant glazes the model to enhance durability. Gypsum powder creates rigid, but brittle models with medium level of detail. The minimum wall thickness is two millimeters at ten layers per millimeter. It is affordable and available in multiple colors.
Visit TechXchange to share 3D printing tips.
Learn more about Digi-Key