Markforged Composite 3D Printing Materials Guide

Markforged Materials

Markforged have an extensive range of composite 3D printing materials that boast extreme abrasion resistance, heat deflection temperatures, impact resistance and strength. In fact, printing with some of these materials yields parts with a higher strength-to-weight ratio than 6061-T6 aluminium.

In this article, we will discuss these composite materials with information about their potential applications.


Compatible with: Onyx One, Onyx Pro, Mark Two, X3, X5, X7. 

Onyx filament is part nylon, part chopped carbon fibre. It is a proprietary Markforged material that offers greater stiffness and better dimensional stability than engineering grade nylon, with twice the strength of traditional engineering-grade thermoplastics, such as ABS, PLA and even tough resins.

This material is compatible with all of the Markforged Industrial Series and Markforged Desktop Series. With it, you can print parts that are up to 40 per cent stiffer than ABS. Because it is a micro-carbon reinforced nylon, onyx also has different thermal properties to most other plastics. For instance, it has minimal thermal deformation, which means less chance of warping on the print bed for consistent, repeatable small-line production.

Onyx prints with a unique texture and appearance courtesy of its chopped carbon fibre content. Parts have a deep matte black finish. They don’t need sanding or finishing. They can be used fresh from the print bed.

Fibreglass CFF

Compatible with: Onyx Pro, Mark Two, X5, X7. 

Fibreglass CFF is 100 per cent engineering-grade fibreglass. It is printed alongside Markforged onyx to fill parts with continuous strands of fibreglass reinforcement for strength and durability. Fibreglass CFF has the highest strength-to-cost ratio of all Markforged materials, making it a superb choice for prototyping.

This material is supported by the Markforged Onyx Pro and Mark Two of the Desktop Series, and the Markforged X5 and X7 of the Industrial Series. With a tensile strength of 590 MPa and a flexural strength of 210 MPa, Fibreglass CFF is extremely strong and printing with it allows you to manufacture parts that are extremely durable. Onyx parts reinforced with this material are 5-times stronger than parts printed with onyx filament alone.

Fibreglass CFF is the lowest-cost composite filament Markforged makes, but it is arguably the most versatile. Use it for prototyping and to manufacture durable, high-quality end-use parts.

HSHT Fibreglass CFF

Compatible with: Mark Two, X7. 

HSHT Fibreglass is a high-temperature version of Fibreglass CFF. It is twice as strong as standard fibreglass filament and has a 30 per cent higher heat deflection temperature. This makes it a more suitable material for high-temperature applications. For example, it can be used to manufacture engine covers for performance cars.

This material is supported by the Markforged Mark Two of the Desktop Series and the X7 of the Industrial Series. It is an advanced composite material designed for high-temperature applications. It has a 150°C heat deflection temperature, so it won’t deform at temperatures up to 150°C. Crucially, this material is also twice as strong as regular fibreglass with a flexural strength of 420 MPa, and a flexural strain at break percentage of 2.2 versus 1.1.

We recommend HSHT Fibreglass for automotive, aerospace and robotics applications where a high heat deflection temperature is needed. However, this material is also suitable for making stronger parts than regular fibreglass allows.

Carbon Fibre CFF

Compatible with: Mark Two, X7. 

Carbon Fibre CFF has the highest strength-to-weight ratio of all Markforged materials. It has a tensile strength of 700 MPa and a flexural strength of 470 MPa; greater than HSHT Fibreglass by 100 MPa and 50 MPa respectively. It also has a compressive strength of 320 MPa, which is more than twice the compressive strength of regular fibreglass.

With carbon fibre, you can 3D print the strongest possible parts. This material is supported by the Markforged Mark Two and X7. It is the most expensive Markforged filament, but it is by far the strongest. It is ideally suited to applications requiring the greatest possible stiffness and strength. Carbon fibre also has the unique characteristic of weighing 40 per cent less than aluminium without losing mechanical properties.

No other material comes close to matching the strength-to-density ratio of carbon fibre. It really is a super material.

Kevlar CFF

Compatible with: Mark Two, X7. 

Kevlar CFF has the best abrasion resistance and the best impact resistance of all Markforged materials. It is also Markforged’s most flexible material. Onyx parts reinforced with continuous strands of Kevlar are extremely resistant to abrasion with outstanding stiffness and strength. This material is favoured where durability under repetitive straining and flexing is needed.

This material is supported by the Markforged Mark Two and X7. It is cheaper than carbon fibre, but more expensive than HSHT fibreglass. In addition to being extremely abrasion and impact resistant, Kevlar CFF is also strong, with a 610 MPa tensile strength which is the second highest in the Markforged filament range. In any case, onyx parts reinforced with this material are significantly more durable than parts printed with ABS.

Kevlar is stronger than ABS, durable under repetitive straining and flexing, and it is extremely abrasion and impact resistant. Choose this material for applications where you need extremely durable parts.