Introduction

With additive manufacturing (AM) now recognized as a capable production process for end-use parts, the demand for high-performance polymers is growing. These materials perform better than engineering thermoplastics like POM and PC, and far better than commodity plastics like PLA. 

Among the most popular materials in the high-performance category is PEEK, a semi-crystalline thermoplastic polymer with excellent strength and chemical resistance. However, while PEEK delivers exceptional material properties, it is difficult to print due to its high melting point, viscosity, and susceptibility to shrinkage and warping. There’s another significant obstacle to PEEK 3D printing: its cost.

This article looks at the total cost of printing with high-performance polymers, considering material costs, hardware costs, and other expenses (annealing, material storage, etc.).

The cost of high-performance polymers

High-performance polymers like PEEK, ULTEM (PEI), PEKK, and PPS are often over x20 more expensive than common thermoplastics like PLA (approx. $15/kg) and ABS (approx. $20/kg). This is down to their desirable material properties like strength and temperature resistance, as well as their being manufactured in smaller quantities than common thermoplastics.

Given that it also costs more to buy materials in 3D printable form (like filament or powder) as opposed to generic forms like pellets, the price of high-performance 3D printing materials can appear steep. That said, a select few 3D printers are able to 3D print PEEK pellets.

Note: It is possible to extrude filament in-house from PEEK pellets, though only high-end extruders — typically priced at $10,000 or more — will reach the required temperatures.

Materials like ULTEM (PEI) offer a slightly cheaper alternative to PEEK, putting high-performance 3D printing within the reach of small and medium-sized companies.

PEEK

PEEK (polyether ether ketone) is a semi-crystalline thermoplastic polymer that is part of the PAEK (polyaryletherketone) family. With very high strength, good chemical resistance, low flammability, and low moisture absorption, PEEK is suitable for demanding industries like aerospace and oil & gas. Its biocompatibility also makes it befitting for medical and dental implants.

Prices for PEEK filament start at around $450/kg — higher than ULTEM and than many metal powders for powder bed fusion (PBF) technologies. An example of PEEK filament is ThermaXPEEK from 3DXTech, which costs $595/kg.

In the PBF area, EOS formerly marketed a PEEK powder for SLS called HP3 but now uses PEKK as its principal high-performance polymer powder.

ULTEM (PEI)

ULTEM or PEI (polyetherimide) is an amorphous thermoplastic similar to PEEK in its material characteristics. PEI is easier to print than PEEK but has lower impact strength, tensile strength, and temperature resistance.

It is possible to buy ULTEM filament at lower prices than PEEK, reflecting its slightly inferior material properties. This high-performance polymer has multiple formulations, namely ULTEM 1010 and ULTEM 9085. ULTEM 1010 provides higher tensile strength, while ULTEM 9085 is more lightweight.

ULTEM also boasts several certifications (e.g., ISO 10993, USP Class VI biocompatibility, and NSF 51), making it easier to adopt than a more or less emerging material like PEEK.

Prices for ULTEM 3D printing filament start at around $250/kg. Sabic’s ULTEM 9085 filament, one popular variety, costs $350/kg.

PEKK

PEKK (polyetherketoneketone) is a semi-crystalline thermoplastic. Like PEEK, it is part of the PAEK family, but has a lower melting point and weaker crystal structure. One advantage of PEKK is that its melting point and crystallization rate are tunable, so its various formulations can offer different thermal and mechanical properties.

There’s a large number of PEKK filaments available, with prices broadly similar to PEEK, if not higher. 3DXTech’s ThermaX PEKK filaments, for example, cost $695/kg, while those from Kimya cost between $830 and $945. Note that PEKK’s greater printability means compatibility with lower-cost hardware, compared to PEEK which requires more expensive systems.

In SLS (Selective Laser Sintering), the HT-23 powder from EOS is a carbon fiber–reinforced PEKK suitable for aerospace and other high-performance applications. The material is targeted at industrial customers, with costs prohibitive for smaller companies.

High-performance Polymer 3D Printers: Pricing

High-performance plastics are available in filament form, but not all FFF 3D printers are equipped to print them. Suitable printers need a high-temperature extruder (343°C or higher), a high-temperature print bed (120°C or higher), and an enclosed, high-temperature build chamber (143°C or higher). 

PEEK has a melting point of 343°C, which limits its use to high-temperature 3D printers. ULTEM is slightly easier to print. Some formulations of PEKK, meanwhile, can be processed by entry-level professional-grade systems.

Material Extrusion

A 3D printer capable of printing PEKK can cost less than $10,000, but ULTEM and PEEK require more demanding high-temperature 3D printers starting at around $30,000.

Large-scale PEEK printing requires an outlay of over $100,000. This is partly because machines in this category are larger, but also because they require a greater degree of environmental temperature control, as larger parts are more susceptible to warping.

Powder Bed Fusion

Some SLS systems can process EOS HT-23, a reinforced PEKK powder. Such machines typically cost hundreds of thousands of dollars.

Other costs incurred by high-performance polymer 3D printing

In addition to hardware and consumables costs, printing with high-performance materials like PEEK, ULTEM, and PEKK can run up additional expenses, such as:

• Annealing: 3D printed PEEK parts may require annealing to de-stress the material and improve mechanical performance. This requires an oven or furnace, which can cost several thousand dollars.
• Storage: High-performance plastics are used for critical applications and must be stored properly to guarantee performance. Storage and in some cases dehumidifying solutions (such as a filament drying unit) should be used.
• Power: High-temperature 3D printers with multiple heat zones use more power than other systems and will incur higher electricity costs.

Is it worth it?

High-performance polymers offer greater strength, chemical resistance, and heat resistance than standard or engineering polymers. For many critical applications, they are worth the expenditure. When considered as a genuine alternative to 3D printed metal — as in many cases they are — they can provide excellent value.