When you’re deciding on what 3D printing materials you should choose for your job, you have to factor in the application, function, and design of your component or product.
3D printing materials come in a wide array of forms. Most consumer 3D printed products are made from thermoplastics. Designers and engineers prefer creating functional prototypes from 3D printing materials that have the same or similar material properties as what’s used in creating the finished product.
Plastics are the most widely adopted 3D printed material - and it comes in filament, resin, granule, and powder forms. Most thermoplastic 3D printing materials can be used in home 3D printing technology and professional applications as well.
Here’s a guide to 3D printed materials’ various properties and uses, starting with the different filament types available for Fused Deposition Modeling (FDM) printers followed by 3D printing materials using other technologies.
Acrylonitrile Butadiene Styrene is the plastic used in Legos. It’s tough, nontoxic and retains color well. (If you’ve ever been barefoot and stepped on a Lego, you know how tough and hard to break ABS is.)
It is also easily shaped as it melts; it becomes pliable at about 220 degrees C (430 F). This does require a large heater to reach that temperature. A printer with a heated print bed is usually needed, otherwise, it will stick. As noted, ABS gets soft and pliable when heated and then sets quickly.
ABS is water and chemical resistant and does produce an unpleasant smell when heated. Because of the chemicals released in the vapor, it needs good ventilation. ABS is broken down by UV radiation, losing its color and becoming brittle, so it is not suited for extended outdoor use.
It is good for making conceptual and functional models and in manufacturing such as for the production of gears or interlocking parts.
Polylactic Acid is a polymer plastic made from biological materials such as cornstarch or sugarcane. It is similar to the material used in biodegradable plastic packaging. It melts between 180 - 200 degrees C, depending on other materials added to it for color and texture.
PLA is tough and resilient but not as heat tolerant as ABS. It begins to deform at temperatures higher than 60 degrees C. It is also not water or chemical resistant. There is a slight smell when it is heated but no toxic odors or vapors.
Because PLA is easier to print with than ABS it is usually the preferred option for low-cost 3D printers. It sticks well to a base covered in white glue or blue painter’s tape, meaning a heated print bed is not needed.
PLA lasts a long time under normal conditions. It is biodegradable and breaks down when buried in the ground. It is not, however, food safe and is a bit brittle. Prints can shatter under stress. Some manufacturers make what they call ‘tough PLA’ by adding chemicals, creating PLA that is less brittle and more heat tolerant.
It works well for general manufacturing 3D printing and painted miniatures.
Polyvinyl Alcohol is a newer class of 3D printing material used for making supports that hold 3D prints in place. It is a synthetic polymer and is water soluble. It melts at about 200 degrees C and releases some pretty unpleasant chemicals when heated to high temperatures.
PVA is used in a standard 3D printer extruder to form parts that support other objects and it sticks well to a heated, glass print bed. Once printing is done, you immerse the part in water and the PVA parts dissolve, leaving the rest of the insoluble print behind. This makes it easier to print complex models that need supports or models with moving parts.
Nylon was originally created as a replacement for silk. It has a high tensile strength (meaning it can hold a lot of weight without breaking), is nontoxic and melts at about 250 degrees C.
Nylon’s use in the 3D printing process is fairly recent. It is becoming more popular because the prints it produces are tough and damage resistant. Because it is widely used in other industries, it is inexpensive and is not damaged by most common chemicals.
Nylon requires higher temperatures to print; 250 degrees C is hotter than a lot of extruders can manage. It is also harder to get nylon to stick to the print bed than with ABS or PLA. It usually needs both a heated print bed and white glue to stick during printing.
It is good for printing utensils that contact food and plant pots that fill with water.
High-density polyethylene (also called high-impact polystyrene or HIPS) is used in pipes and recyclable packaging such as plastic bottles and packages, those with the recycling ID code 2.
It is light, flexible and easy to dye and mold. It melts at about 230 degrees C. HDPE is sometimes used instead of ABS because its prints come out lighter and stronger than those using ABS. It requires higher temperatures for printing and can release unpleasant fumes if the temperature is too high.
It is resistant to most chemicals but does dissolve in limoleme, a common solvent in industrial cleaners. HDPE’s solubility in limoleme means it can be used for printing supports which can be dissolved by immersion in limoleme, leaving materials like ABS or PLA unaffected.
It does require an extruder that can reach higher temperatures and a heated print bed. HDPE also has a tendency to contract as it cools, which can lead to warped prints.
It works well for lightweight prints and as supports for ABS prints.
Polyethylene terephthalate is similar to polyester, it is also known as t-glase. It melts at around 230 degrees C and cools into a rigid solid resembling glass. It can be dyed while maintaining its glass-like characteristics, therefore it is available in a variety of colors. It is strong and resilient but has to be printed slowly to make sure the layers adhere properly.
It is approved for food use, so it is good for printing utensils, cups, water bottles, and other items that come into contact with food.
This a variant of PET that has been combined with glycol. It has high transparency and can be printed at lower temperatures with increased flow speed, therefore allowing faster prints.
Because of its weather resistance, it is often used for garden appliances and is also food safe so it is useful for food containers.
Despite the name, these printer filaments are not made of wood. Rather they contain very fine wood particles that are combined with PLA and a polymer glue, binding them together. There are versions available for many types of wood, from bamboo to ebony to mahogany. These types of filaments allow the color of the printed material to be changed by varying the temperature. With higher temperatures, the wood particles have a darker, burned look.
Wood filaments are printed the same way as PLA filaments. Extruder temperatures are similar and white glue is used to help the print stick to the print bed. The material does need extra finishing, like sanding or a mild abrasive to bring out the wood look.
It is often used for sculptures or wood-like carvings.
Often referred to as “gypsum” or “multicolor”, sandstone can create full-color parts in one process. A protective coating of epoxy resin is often added to enhance color quality and strength as components from this material can be fragile.
It is mostly used for architectural models, conceptual prototypes and art projects.
Using fine particles of clay combined with certain minerals and water, ceramic 3D prints can be turned into solid pottery using a kiln. They then can be glazed and kilned again for a glossy finish. Ceramic 3D prints are made using FDM or stereolithography (SLA). They are heat resistant and durable.
They are most often used for making art projects, tableware, and dental implants.
Similar to wood filaments, metal filaments are made of very finely ground metals combined with PLA and a polymer to bind them and they print like PLA. When the final print is polished, it has the look and feel of metals.
Available versions include steel, brass, bronze, and copper. Metal filaments are not as heavy as solid metal, therefore, a bronze statue, for example, would not weigh as much as a cast bronze version. Also, because the metal particles are bound by PLA and glue, they will not conduct electricity.
Metal filaments are good for printing metal sculptures and figurines.
Carbon fiber filaments combine carbon fiber and another type of filament material, such as nylon, to produce some of the advantages of carbon fiber like rigidity, strength, and low weight. Caution should be used when printing with carbon fiber as it is extremely abrasive and can wear out the hot end of an extruder very quickly.
It is good for structural prints that need to be strong and lightweight.
3D printing materials usually seek to be rigid and strong. However, strength and rigidity are not always the end goal, and that’s where Flexible Filaments come in. They produce rubber-like, flexible prints. MakerBot’s Flexible Filament becomes flexible when it is put in hot water. It can then be reshaped or molded into a tight-fitting spot before it cools and becomes rigid again.
Flexible filaments work well for producing wearable prints, flexible joints, phone covers, and toys.
Graphene is a form of carbon that conducts electricity. Combined with PLA it allows printing of electrical circuits without the need for adding wires. Care is required when printing as the layers of print do not stick together as well as normal PLA. They are also brittle, so if they are bent the conductive circuit is broken and they can no longer conduct electricity. Usually, these circuits are produced by printing a PLA case around the electrically conductive parts, protecting and strengthening them.
Conductive filaments are great for printing things like touch buttons, wearable electronics or electrically conductive styluses.
Cobalt Chromium is used in high-performance 3D printing applications. Sometimes called a “superalloy”, it is known for its strength and also its temperature and corrosion resistance. The 3D printing technology required for its use is Direct Metal Laser Sintering aka Selective Laser Melting (SLM).
It is usually used in components for the aerospace industry, such as jet engines or turbines but also works for components with fine features such as with medical applications.
Inconel is another superalloy, composed primarily of nickel and chrome. It is produced to withstand the most extreme environments and has a high-temperature resistance. Because of its strength, it is difficult to machine, therefore Direct Metal Laser Sintering is the preferred method of shaping it.
Due to its resistance to high pressures, it is used for manufacturing airplane black boxes or even rocket engine parts.
Common everyday copy paper has a place in 3D printing. Using Selective Deposition Lamination (SDL) parts made this way have a feel like wood and are fully colored. Paper 3D prints lack durability and the detail found with PolyJet Resins or gypsum.
It is typically used for architectural and conceptual models.
Stereolithography (SLA) resins were developed to simulate the properties of “traditional” 3D printing materials. There are SLA materials that have the durability of ABS or the bio-compatibility of PLA. Some have similar properties of wax or ceramics.
Resins work well for functional and concept models; they can be used to produce large parts in a short time with a high degree of detail. High-temperature resins are a cost-effective way of producing injection molds for the small-scale production of prototypes.
Similar to SLA resins, PolyJet resins simulate properties of “traditional” 3D printing materials. The biggest difference between them is the ability of PolyJet resins to combine up to three 3D printing materials to create new custom materials for a part, with the optimal blend of durability, heat resistance, strength, transparency, etc., along with the full range of colors.
Parts printed with PolyJet resins not only produce a visual approximation of a finished product, they also simulate its touch and feel.
They are great for producing color prototypes of consumer products for testing with consumer groups. Other applications include conceptual models, art products, jewelry, medical manufacturing, and tooling.
Alumide is nylon combined with aluminum particles. It is much like nylon in its durability and physical properties, the difference being the shiny, durable, and porous surface finish. Parts printed with Alumide are tough, accurate in size, and suited for long-term use.
It uses Selective Laser Sintering (SLS) technology for DIY projects, functional prototypes, and manufacturing.
Polyetheretherketone uses FDM or SLS technology for the production of high-performance parts. Plastics of this type are highly resistant to stress, temperature, and chemicals and they can be exposed to X-ray and gamma radiation. They are easy to machine and fabricate but require a 3D printer capable of reaching 400 degrees C.
PEEK 3D printing materials are used in the most demanding applications in the automotive, aerospace, chemical, and medical industries including the production of medical instruments and semiconductor components.
Wax 3D prints are used with SLA or PolyJet resins as an important stage of the production process rather than as an end product. Complex structures that need supports while being printed use waxes that can be melted off the final product.
They are often used to make high-resolution molds for creating customizable jewelry at a low cost. Wax 3D prints are also used in the dental medicine industry for casting various dental appliances.
As you can see, the array of 3D printing materials today is mind-boggling. Tasks formerly performed only by artisans are now automated and can be performed by anyone with the proper training in 3D modeling and printing, revolutionizing the way we make things.