3D Printing Materials & Technologies Guide
From your first prototype to a NASA rocket engine — everything you need to know about additive manufacturing materials, technologies, and certifications.
Materials
Every 3D printing material falls into one of five categories. The material determines what technology is used, what properties the part has, and what it costs.
Metal 3D printing melts fine metal powder with a laser, layer by layer, producing fully dense parts with mechanical properties equal to machined metal.
- 316L Stainless Steel — corrosion resistant, biocompatible, most common metal AM material
- Titanium Ti64 — strongest lightweight metal, 45% lighter than steel, used in aerospace and implants
- Inconel 625/718 — nickel superalloy, retains strength at 980°C, used in jet engines and rockets
- Aluminum AlSi10Mg — lightweight, good thermal conductivity, automotive and aerospace
- Cobalt Chrome — extremely hard and wear resistant, dental crowns and joint replacements
- Pure Copper — highest electrical and thermal conductivity, rocket cooling channels
The most widely used materials in 3D printing. Plastics range from soft and flexible to rigid and strong, processed by melting filament (FDM) or fusing powder (SLS/MJF).
- Nylon PA-12 — tough, slightly flexible, chemical resistant, most popular SLS/MJF material
- TPU — rubber-like, stretches up to 600%, used for shoe soles, grips, gaskets
- ABS / ABS-M30 — classic engineering plastic, sandable and paintable, good for enclosures
- ASA — UV and weather resistant ABS, ideal for outdoor applications
- Polycarbonate — very tough, optically clear available, high impact resistance
- PETG — easy to print, food-safe grades available, good chemical resistance
Liquid polymers cured by UV or visible light. Resins offer the finest surface finish and highest detail of any 3D printing category. Used in SLA, DLP, and PolyJet processes.
- Somos WaterShed XC — near-colorless, water resistant, simulates ABS
- Accura Series — rigid, flexible, and tough variants simulating engineering plastics
- Vero PolyJet — full color spectrum, multi-material, 16 micron layer resolution
- EPU/RPU Carbon DLS — production-grade, isotropic, used in Nike shoe midsoles
- Agilus30 — rubber-like, 27A-95A Shore hardness, for soft-touch surfaces
- Biocompatible MED610/620 — USP Class VI, for surgical guides and dental devices
Fiber-reinforced materials delivering metal-like stiffness at a fraction of the weight. Carbon fiber and fiberglass are embedded in plastic matrices.
- Carbon Fiber / Nylon 12 — 3x stiffer than plain nylon, lighter than aluminum
- Carbon Fiber / PEEK — highest performance composite, approaches aluminum strength
- Fiberglass / Nylon — electrically insulating, lower cost than carbon fiber
- PPA-CF — carbon filled high-temp nylon for under-hood automotive
- PPS-CF — exceptional chemical resistance, used in pumps and valves
High-performance polymers engineered for extreme conditions — high temperatures, harsh chemicals, medical sterilization, and aerospace certification.
- PEEK — benchmark high-performance plastic, 250°C continuous, resists all chemicals
- Ultem 9085 — FAR 25.853 certified for aircraft interiors, flame/smoke/toxicity rated
- Ultem 1010 — highest temp FDM material, steam sterilizable, USP Class VI
- Antero/PEKK — ESD-safe variant for aerospace electronics, low outgassing
- PPSF/PPSU — most chemically resistant FDM material, repeated autoclave compatible
- ABS ESD / Diran — electrostatic discharge safe for electronics manufacturing
Technologies
The technology determines how a part is built — which materials can be used, what surface finish is achieved, and what the part costs.
Which Process for My Part?
Every process leaves its fingerprint on the part. Here is what to honestly expect — no surprises when the box arrives.
About those lines. FDM parts will show layer lines — thin ridges stacked up the sides of the print, like a topographic map. That is not a defect and the shop did nothing wrong; it is how the process works. Every process has its own version of this: resin has support nubs, SLS feels grainy, metal comes out rough. If you need a glass-smooth finish, say so up front — the shop can sand, smooth, or paint it, but that is extra work with extra cost.
FDM — melted plastic filament
Finish: visible layer lines. Sturdy, honest, a little ridged.
Strength: good — strongest pulling along the layers, weaker pulling them apart.
Detail / cost: chunkier details; the cheapest way to print big.
Pick it when: large parts, low cost, functional prototypes and brackets.
SLA — liquid resin, cured by light
Finish: smooth — the closest to injection-molded. Small nubs where supports were clipped off.
Strength: stiff but can be brittle; tougher engineering resins exist — ask.
Detail / cost: excellent fine detail; mid-range cost.
Pick it when: visual models, detailed small parts, smooth surface matters.
SLS — nylon powder, fused by laser
Finish: grainy matte, a little like fine sandpaper. Takes dye well.
Strength: tough functional nylon; no supports needed, so wild geometries print fine.
Detail / cost: good detail; mid-to-high cost.
Pick it when: working parts, complex shapes, small batches of end-use pieces.
MJF — nylon powder, fused by ink + heat
Finish: grainy matte like SLS, slightly crisper detail.
Strength: tough nylon, similar to SLS.
Detail / cost: sharp detail; often the best price at volume.
Pick it when: SLS-type parts where you want quantity pricing.
DMLS / SLM — metal powder, melted by laser
Finish: rough as-printed, like a casting. Precision surfaces get CNC-machined afterward.
Strength: real, fully dense metal — titanium, stainless, inconel.
Detail / cost: good detail; the most expensive process here.
Pick it when: metal parts too complex to machine, or with internal channels.
PolyJet — jetted resin, full color
Finish: the smoothest plastic print — and full color in a single print.
Strength: brittle. These are display pieces, not working parts.
Detail / cost: finest detail of any plastic process; high cost.
Pick it when: looks-like prototypes, medical models, anything where appearance is the job.
Rule of thumb: resin for how it looks, nylon for how it works, FDM for how much it costs, metal for when plastic won't do. Still unsure? Put the job on the Request Board describing what the part has to do — the shops will steer you right.
Certifications
Certifications tell you a bureau meets specific quality and compliance standards. For aerospace, defense, and medical work — certifications are not optional.
The baseline quality management system standard. Means the bureau has documented processes, quality controls, and continuous improvement systems. Required by most serious buyers.
Find certified bureaus →The aerospace quality standard — built on ISO 9001 with additional requirements for risk management, configuration control, and first article inspection. Required for flight hardware.
Find certified bureaus →Medical device quality management standard. Required for any part that goes in or on the human body. Covers design controls, traceability, and sterile manufacturing.
Find certified bureaus →International Traffic in Arms Regulations. Required for defense articles and services. Means the bureau controls who can access their facility and data. Essential for military work.
Find certified bureaus →Cybersecurity Maturity Model Certification. Required for DoD contractors. Ensures the bureau protects controlled unclassified information (CUI) digitally.
Find certified bureaus →National Aerospace and Defense Contractors Accreditation Program. The gold standard for aerospace special processes. Required by Boeing, Lockheed, GE Aviation, and NASA suppliers.
Find certified bureaus →The facility is registered with the FDA. Required for medical device manufacturing. Means the FDA can inspect the facility and the bureau follows FDA regulations.
Find certified bureaus →National Institute of Standards and Technology cybersecurity framework. Required for contractors handling Controlled Unclassified Information for the US government.
Find certified bureaus →How to Choose the Right Bureau
A simple framework for matching your project to the right service bureau.
Start with your material
Do you need a metal, plastic, resin, or composite part? The material narrows your technology options immediately. If you need titanium, you need DMLS. If you need flexible rubber-like parts, you need TPU with SLS or FDM.
Consider your volume
1–10 parts: any bureau works. 100–1,000 parts: look for MJF or SLS bureaus with production capability. 1,000+ parts: find bureaus that specialize in production runs and have multiple machines.
Check certifications
Aerospace parts need AS9100. Medical implants need ISO 13485. Defense work needs ITAR. Never skip this step — using an uncertified bureau for certified work can invalidate your entire supply chain.
Match lead time to your need
Prototypes: look for bureaus offering 24–48 hour turnaround. Production: plan for 5–15 business days. Rush orders cost 2–3x more. Build lead time into your project schedule.
Ask about post-processing
A raw 3D printed part often needs finishing — sanding, painting, dyeing, vapor smoothing, CNC machining, or heat treatment. Find a bureau that offers what you need in-house to save time and cost.
Verify quality processes
Ask about their first article inspection, dimensional reporting, and material certifications. For critical parts, require a Certificate of Conformance (CoC) with every order.