Carbon Steel 3D Printing Reality & Alternatives

Karl Gillihan

🏗️ CARBON STEEL

Carbon Steel 3D Printing: Why 1018, 1045, and A36 Rarely Get Printed

Here is the blunt answer most directories won't give you: plain carbon steels like 1018, 1045, and A36 are almost never 3D printed, and you should usually machine or fabricate them instead. Additive metal works best with alloys tuned for the melt pool, and the AM steel ecosystem skipped past mild steel to low-alloy tool and maraging grades. This page explains what gets printed when someone says 'steel,' and when to walk away from AM entirely.

ISO 9001AS9100

Why Plain Carbon Steel Is the Wrong Material for AM

Grades like 1018, 1045, and A36 are cheap, ubiquitous, and supremely easy to machine, weld, and form from bar or plate. That is exactly why nobody printed them: there is no economic or geometric reason to pay additive prices for a material whose entire value proposition is being cheap and workable in conventional form. Powder for true 1018 or A36 is barely a commercial product, and when these compositions are melted in LPBF, the high cooling rate forms hard, brittle martensite that needs immediate stress relief or it cracks. When a vendor says they 'print carbon/low-alloy steel,' they almost always mean a designed-for-AM grade: 4140-like low-alloy steel powders, 20MnCr5 case-hardening steel, or maraging steel (18Ni-300). These print to high density and respond to heat treatment predictably. 4140 itself is sometimes printed for tooling and oil-and-gas hardware because its chromium-molybdenum chemistry hardens well and tolerates the thermal cycling better than plain carbon grades.

The Honest Alternatives Buyers Actually Use

If you need a part in 1018 or A36, the right processes are machining from bar/plate, laser or waterjet cutting plus weldment fabrication, or casting for complex shapes at volume. These deliver true wrought or cast properties at a fraction of AM cost, with full weldability intact. A36 in particular is a structural plate grade — printing it makes no sense when it exists to be cut and welded into frames and brackets. If the part's value is genuinely in complex internal geometry or consolidation that can't be machined, the move is to substitute an AM-friendly alloy of similar strength: maraging steel or 4140-type powder for high-strength structural needs, 17-4PH stainless if corrosion matters, or a low-alloy AM steel for general use. You change the material spec to fit the process, not the other way around. Confirm the substitution is acceptable to your engineering and qualification requirements before committing.

When 4140-Type Low-Alloy AM Does Make Sense

4140 (and its AM-tuned cousins) is the one grade in this family that sees real additive use. Printed and then quench-and-tempered, AM 4140-type steel reaches roughly 950-1200 MPa ultimate with good toughness, suiting downhole tools, custom tooling, and heavy-equipment components with complex cores. As-built density above 99.5% is achievable, but these steels are crack-prone during the build, so heated build plates (often 200°C+) and immediate stress relief are essential to avoid quench cracking from the layer-by-layer thermal shock. Expect as-built roughness around Ra 6-15 µm and to machine all critical surfaces afterward. Carburizing or nitriding can be applied for wear surfaces. Even here, the supplier base is narrower than for stainless or titanium, and you should confirm the shop has validated parameters and a heat-treat recipe for the specific powder, not just generic '4140.'

Frequently Asked Questions

Practically, no — and you shouldn't want to. There is essentially no commercial powder bed market for plain 1018 or A36 because these grades exist to be cheap and easy to machine, weld, and fabricate. Melting them in LPBF produces hard, crack-prone martensite that requires immediate stress relief, and you'd pay $150-400+ per small part for a material that costs pennies per pound as bar stock. If you have a drawing calling out 1018 or A36, the correct sourcing is CNC machining from bar/plate, or laser/waterjet cutting plus welding for fabricated structures. Reserve additive manufacturing for geometry that conventional methods cannot produce, and in that case substitute an AM-designed alloy (maraging steel, 4140-type, or 17-4PH) of comparable strength after confirming the substitution meets your engineering requirements.

The mature AM steels are: maraging steel 18Ni-300 (prints to ~99.8% density, ages to 1800-2000 MPa ultimate, ideal for tooling and high-strength parts); 17-4PH and 316L stainless (the most common, well-characterized); H13 and other tool steels for conformal-cooled molds; and low-alloy 4140-type powders for general high-strength work. These were chosen because their chemistries tolerate rapid solidification and respond predictably to post-print heat treatment. Plain carbon grades like 1018, 1045, and A36 are not in this list. If your design needs a printed steel, pick from the qualified AM grades and match strength/hardness rather than insisting on a conventional carbon grade. A supplier on ManufacturingBase can advise which AM steel matches your mechanical target.

After proper heat treatment, AM 4140-type steel reaches comparable strength — roughly 950-1200 MPa ultimate quenched and tempered — but there are caveats. The as-built microstructure differs from wrought, and fatigue performance depends heavily on closing internal porosity, so fatigue-critical parts should be HIP'd. AM 4140 is also genuinely difficult to print: it cracks during the build without a heated plate (typically 200°C or higher) and prompt stress relief, so supplier process control matters enormously. For a simple shaft or block, machining wrought 4140 bar is cheaper and gives guaranteed properties. AM 4140 earns its place only when complex internal geometry or consolidation justifies it. Always require the supplier to certify the post-print heat-treat condition and hardness, and consider HIP for any cyclically loaded component.

Because the entire economic logic of carbon steel runs opposite to additive manufacturing. Carbon steel is the cheapest structural metal precisely because it's mass-produced as bar, plate, and sheet and is trivially machined, welded, and stamped. Additive manufacturing is a low-volume, geometry-driven, premium process — its cost floor (machine time, powder handling, post-processing) is far above what carbon steel parts are worth in conventional form. You'd be spending titanium-process money to make a mild-steel part. There's also a metallurgical reason: plain carbon grades crack readily in the melt pool and add powder-atomization and crack-prevention costs with no payoff. The market simply never developed because no rational buyer would pay it. For carbon steel parts, conventional manufacturing wins every time on cost; use AM only by substituting a purpose-built alloy.

Last updated: July 2026

Find Carbon Steel 3D Printing / Additive Manufacturing Suppliers

Search verified shops that handle Carbon Steel 3d printing / additive manufacturing.

Search Manufacturers →Get Your Shop Listed (Free)

No logins. No email gates. Just results.