What are the most common types of 3D printing materials?

The short answer

The six materials that cover most parts

Everything else is a variation on these. The table below pairs each one with the property that usually decides the choice, because price and strength are rarely the deciding factor on their own.

What each material is actually for

PLA is the default starting point: it prints cleanly on any machine, holds sharp detail, sands and paints well, and costs the least. Its glass transition sits around 50 to 60 degrees Celsius, so a part left in a hot vehicle or near a heat source will creep under load. Treat PLA as a proof-of-concept material rather than a final one.

PETG is where functional printing should start. It is stronger than PLA with better temperature resistance, tolerates mild chemical exposure without crazing, and is slightly flexible, which lets it absorb impact rather than crack. Layer adhesion is better than ABS without the warping, and it needs no enclosure. For brackets, clips, enclosures and general mechanical parts it is the sensible default when PLA is not strong enough.

ABS and ASA are the heat-resistant pair. ABS tolerates higher impact and temperature but warps and gives off fumes, so it wants an enclosed, ventilated machine. ASA is the UV-stabilised version: it holds its properties after months of sunlight where standard ABS yellows and embrittles, which makes it the choice for anything that lives outdoors. Both sand and vapour-smooth well, which matters for cosmetic parts.

TPU is a sidestep rather than an upgrade - it is chosen when the requirement is flexibility, not strength. It stretches beyond 200 percent elongation in the softer grades, which suits gaskets, seals, grips, strain reliefs and vibration dampers. It prints slowly, and a direct-drive extruder makes the flexible path much shorter and more reliable.

Nylon PA12 is the engineering tier. It resists fatigue and wear far better than PETG, which is what makes it the material for gears, living hinges, snap tabs and load-bearing brackets. The catch is moisture: nylon is hygroscopic, so it must be dried before printing and stored dry, or the part comes out with voids and reduced stiffness. Surface finish on FDM nylon is also rougher than PETG or PLA. Printing nylon as SLS powder raises the service temperature to roughly 150 to 170 degrees and removes the need for supports entirely, at a higher cost per part.

Above these materials sit the composites and metals. Carbon fibre and glass filled nylon reach 70 to 110 MPa and add stiffness rather than toughness, which makes them the choice for frames and jigs where deflection matters; they need a hardened nozzle. Metal printing such as 316L via laser powder bed sits around 540 MPa - roughly ten times PLA - and is a different process with a different cost structure and post-processing route, not a filament upgrade.

How hot a part can work

Temperature is the requirement that most often surprises people, because a material that is strong at room temperature can lose most of its usable stiffness well below the temperature of boiling water.

What each material costs

Price per kilogram is a poor guide on its own, because a spool that fails three times costs more than the material saved. The useful way to read the chart below is to buy the cheapest material that satisfies the temperature and load case, and step up only when a specific requirement forces it.

Choosing by the part, not by the printer

Where each material fails

• PLA in a warm environment. Softening starts around 50 to 60 degrees; a part under load will creep rather than fail cleanly, so the failure appears as a distorted geometry.
• ABS without an enclosure. Differential cooling warps the part and splits layers, so the printed properties come in below the datasheet.
• Nylon with wet filament. Absorbed moisture turns to steam in the nozzle, causing bubbles, voids and a visibly rough surface with reduced stiffness.
• TPU on a long bowden path. Flexible filament buckles before it reaches the nozzle, which shows up as inconsistent extrusion rather than a clean failure.
• Composites as a toughness fix. Chopped fibre increases stiffness and reduces flexibility, so a part designed to bend will crack instead.

Printed prototypes and production parts at SOMI Custom Parts

We print SLA, SLS, FDM, MJF and SLM parts for prototypes, jigs and low-volume production, and we will say when the geometry or the load case means a moulded or machined part is the cheaper answer over the volume you are planning. Send a model and a quantity: see FDM 3D printing, SLS 3D printing, or open a project through our inquiry form.