The Right Markforged Material: Base and Continuous Fibers

When it comes to 3D printing strong, end-use parts, Markforged stands in a class of its own. Its composite printing technology combines advanced base materials with continuous fiber reinforcement to produce parts that rival metal in strength—while keeping weight and lead times low.

At UPTIVE, we offer a full suite of Markforged materials to help engineers and manufacturers build reliable, functional parts across industries like aerospace, automotive, medical, industrial equipment, and more. Whether you’re prototyping, fixturing, or creating production-ready components, choosing the right material is critical.

Here’s a breakdown of all available Markforged base materials and continuous fibers—along with key characteristics, applications, and tips for choosing the right fit.

Base Materials

These are the primary materials used in Markforged composite 3D printing. They provide the form, base strength, and surface finish for your part.

Onyx

UPTIVE tip: Onyx is often reinforced with continuous fibers to create parts as strong as aluminum—but even alone, it’s ideal for many functional applications.

Onyx FR (Flame Retardant)

What it is:
A flame-retardant version of Onyx, designed to meet UL 94 V-0 standards.

Key characteristics:

• Flame-retardant and self-extinguishing
• High strength and stiffness
• Good chemical resistance

Best for:

• Aerospace and automotive interiors
• Electronics housings
• Any application requiring fire-safe materials

Used in:
Aerospace, transportation, defense, electronics

UPTIVE tip: Combine Onyx FR with carbon fiber reinforcement to produce strong, fire-resistant parts for regulated industries.

Onyx ESD

What it is:
An ESD-safe variant of Onyx, designed for applications where static discharge is a concern.

Key characteristics:

• Electrostatic discharge safe
• Strong and dimensionally stable
• Excellent surface finish

Best for:

• Electronics manufacturing tools
• PCB handling equipment
• Semiconductor industry applications

Used in:
Electronics, medical, robotics, automation

UPTIVE tip: Onyx ESD is ideal for work holding and protective enclosures near sensitive electronics.

CONTINUOUS FIBERS

Markforged’s continuous fiber reinforcement makes it possible to 3D print composite parts with strength comparable to metal. These fibers are embedded within base materials like Onyx during the printing process.

Carbon Fiber

What it is:
The strongest continuous fiber Markforged offers. It’s lightweight, stiff, and ideal for high-performance applications.

Key characteristics:

• 10x stronger than Onyx alone
• Extremely high stiffness-to-weight ratio
• Near-aluminum strength

Best for:

• Structural components
• Lightweight tooling
• Automotive brackets and mounts

Used in:
Aerospace, automotive, industrial machinery

UPTIVE tip: Carbon fiber is your go-to reinforcement when you need parts to carry loads or replace metal.

Kevlar®

What it is:
A tough and impact-resistant fiber ideal for parts that take a beating.

Key characteristics:

• High impact resistance
• Flexible and durable
• Great for absorbing energy

Best for:

• Protective covers
• Fixtures with frequent handling
• Wear-resistant tooling

Used in:
Defense, automation, rugged industrial environments

UPTIVE tip: Kevlar is ideal for jigs or enclosures that need to absorb shock without cracking.

Fiberglass

What it is:
A strong, affordable reinforcement fiber that’s ideal for cost-effective parts with good mechanical strength.

Key characteristics:

• 2.5x stronger than Onyx alone
• More affordable than carbon fiber
• Good for high-load applications

Best for:

• Fixtures
• Mechanical brackets
• Structural supports

Used in:
General manufacturing, industrial tooling

UPTIVE tip: Fiberglass is a great middle-ground reinforcement option when you need strength on a budget.

HSHT Fiberglass (High Strength High Temperature)

What it is:
A high-temperature fiberglass designed for parts that must perform under both load and heat.

Key characteristics:

• Excellent heat resistance (up to 145°C+)
• Strong under thermal stress
• Good mechanical durability

Best for:

• Molds
• Thermal fixtures
• Under-the-hood automotive parts

Used in:
Aerospace, automotive, industrial processing

UPTIVE tip: HSHT fiberglass is ideal for parts exposed to heat and stress—like in molding or engine bay environments.

Which Material is Right for You?

The best material depends on your part’s function, environment, and mechanical needs. At Uptive, we help you weigh your options and optimize your design for manufacturability and performance.

Here are a few starting points:

• Need the strongest part possible? → Onyx + Carbon Fiber
• Building prototypes or visual models? → Precise PLA or Nylon White
• Concerned about heat or flame? → Onyx FR or HSHT Fiberglass
• Working near electronics? → Onyx ESD
• Want a part that can flex or take impact? → Kevlar or Nylon White

Let UPTIVE Help You Get It Right

With in-house Markforged capabilities and years of experience working with engineers and product developers, Uptive makes it easy to select the best material for your part, your timeline, and your budget.

Whether you’re prototyping, testing, or building end-use parts, our team is ready to help you move fast and stay sharp—without compromising performance.

Ready to start your next project? Get a quote or reach out to talk materials with our team.