PLA (poly lactic acid) and ABS (Acrylonitrile Butadiene Styrene) are popular thermoplastic materials for personal and professional grade 3D printing systems. When deciding between PLA and ABS material, it depends on your application needs.
PLA is a plant-based material, typically made from sugar beets, corn and wheat. It is compostable and biodegradeable, and can be used to build parts that will come into contact with food. Part of its popularity comes from its ability to take color well. Naturally translucent, when colored it displays a nice glossy look and feel.
PLA delivers printed parts with good dimensional accuracy. It is strong, and more rigid than ABS. In filament form, it has a more liquid-like flow when moving through the 3D printer nozzle; this flow helps extruded layers bind together well, improving part strength.
But PLA has a lower melting temperature than ABS, thus it can droop and lose its shape when exposed to environments with high ambient temperatures, or resting under hot light sources. It will also loose its shape over time if not treated or finished with another material, like paint or other sealant.
PLA is said to have a slight smell when printed, an odor that reminds some of a semi-sweet cooking oil.
ABS material, on the other hand, is a petroleum based plastic. It is a strong material with a bit more flexibility than PLA, making it suitable to use when printing interlocking pieces or pin connected pieces. It offers good impact resistance and toughness. It is flammable, and is not safe to use for products that may come into contact with food.
Some users notice a smell when printing with ABS material. Research has shown that the printer temperature is a factor in the odor. And recently, research has shown that this material gives off ultrafine particles (UFPs) regardless of what 3D printer it is used in. Therefore, proper ventilation is recommended for all 3D printers if you print with ABS material.
ABS material needs a heated printer bed, otherwise the extruded material tends to curl upwards, compromising part dimensional accuracy. In addition, the printer bed should be smooth, flat, and clean to help control curling.
Part finishing options for ABS parts include sanding and machining, which makes it an attractive choice for parts built for function. Users can also use Acetone to finish the parts or smooth out the stair-stepping effect common in extrusion-based printers. ABS material is easier to recycle than PLA.
ABS material offers strength, flexibility, and machinability for function end-use parts. Plus, it has a long life span.