Metal 3D Printing — SLM / DMLS
Industrial metal 3D printing in titanium, stainless steel and aluminium
Full-density metal parts printed layer by layer, heat-treated and machined to spec. For aerospace brackets, medical implants, mold inserts with conformal cooling and topology-optimised structural parts. Honest lead times, honest pricing.
As-printed accuracy (features ≤100 mm)
- 1Upload STEP + PDF drawing with tolerances and standard
- 2DFAM review — supports, orientation, machining allowance
- 3Print, stress relief, support removal, optional HIP
- 4CNC finishing, inspection report, ship
Quick answer
Metal 3D printing (SLM / DMLS) uses a high-power laser to fully melt metal powder layer by layer in an inert-gas chamber. Choose it for parts with internal channels, topology optimisation, single-piece consolidation of assemblies, or low-volume production in stainless steel 316L, titanium Ti6Al4V, aluminium AlSi10Mg, Inconel, cobalt-chrome or maraging steel. Costs are 5–10× polymer equivalents; heat treatment and machining are mandatory, not optional.
Applications
What metal 3D printing is good for
Metal AM is the right answer when geometry, weight or single-piece consolidation is worth the cost — otherwise machining wins.
- Aerospace brackets and structural parts with topology optimisation
- Injection mold and die-casting inserts with conformal cooling channels
- Medical implants and instruments in Ti6Al4V (ELI grade for implants)
- Dental frameworks and prosthetics in cobalt-chrome
- Heat exchangers with internal fin geometries impossible to machine
- Low-volume production of end-use parts (1–100 units) in exotic alloys
- Consolidation of multi-part welded assemblies into single components
- Legacy spare parts and obsolete components (aerospace, defence, industrial)
- Robotics end-effectors and grippers in lightweight AlSi10Mg
Process
How SLM / DMLS works
Four stages plus mandatory post-processing.
File prep and support design
Part is oriented to minimise supports and residual stress. Supports are engineered (not auto-generated) for critical features and easy removal.
Laser melting in inert gas
Argon (or nitrogen for aluminium) chamber. A 200–1,000 W laser fully melts the powder layer by layer. Layer height 20–60 µm depending on alloy.
Stress relief and removal
Stress-relief heat treatment on the build plate is mandatory before separation. Then wire EDM or bandsaw removes the part.
Finishing and inspection
Support removal, optional HIP, CNC machining of functional surfaces, surface finishing (blast, polish, anodise, passivate), CMM inspection where called out.
Specs
Alloys and specifications
Alloys
- Stainless 316L — ~530 MPa UTS, corrosion-resistant. Marine, medical instruments, food, chemical.
- 17-4PH — ~1,050 MPa UTS after H900. Hardenable, higher strength than 316L. Tooling, hydraulics.
- Titanium Ti6Al4V (Grade 5 / ELI Grade 23) — ~950 MPa UTS, 4.4 g/cm³. Aerospace, medical implants.
- Aluminium AlSi10Mg — ~350 MPa UTS after T6, 2.7 g/cm³. Structural, thermal, brackets, heat exchangers.
- Inconel 625 / 718 — ~900–1,200 MPa UTS. High-temperature aerospace, energy, turbines.
- Cobalt-Chrome (CoCrMo) — biocompatible, wear-resistant. Dental, orthopaedic, high-wear parts.
- Maraging Steel (1.2709 / M300) — hardens to 50-58 HRC. Injection mold inserts, tooling.
Key specs
- Build volume (typical)
- 250 × 250 × 325 mm
- Build volume (large format)
- up to 800 × 400 × 500 mm
- Layer height
- 20–60 µm (alloy dependent)
- Min wall thickness
- 0.4 mm (0.8 mm recommended)
- Min feature size
- 0.3 mm
- Dimensional accuracy (as-printed)
- ±0.2 mm (features ≤100 mm)
- Surface finish (as-printed)
- Ra 6–15 µm
- Density after HIP
- >99.9%
Case example
Typical case: topology-optimised aerospace bracket
A tier-1 aerospace supplier had a machined-aluminium bracket weighing 1.8 kg per unit across a 40-part-per-aircraft assembly. Certification allowed a like-for-like topology re-design. The team ran a topology optimisation targeting a 50% mass reduction while holding the original stiffness envelope.
We printed the re-designed bracket in Ti6Al4V (Grade 5), HIP-treated, then CNC-finished the mating faces and bolt holes. Result: final weight 720 g (−60%), €890 per bracket at 40 units, fully certified to AMS 4998. Saves ~43 kg per aircraft — pays for itself in fuel across the operating life.
Decision
When to choose metal 3D printing vs alternatives
- vs CNC machining: choose metal AM for internal channels, lattices, topology-optimised parts and assembly consolidation. Machining wins for simple geometry and volumes above ~500.
- vs casting: choose metal AM for volumes under ~200 where tooling cost is prohibitive, or for geometry casting cannot achieve.
- vs metal MIM (Metal Injection Molding): choose metal AM for larger parts and low volume. MIM wins for small parts at 5,000+ volumes.
- vs SLS or MJF (polymer): choose metal AM only if the load case, temperature or wear demands it — polymer nylons handle a lot more than people expect at 10× lower cost.
- vs FDM in ULTEM/PEEK: choose metal AM when temperature exceeds ~230°C, load exceeds engineering polymer limits or the application requires metal biocompatibility.
- vs welded assembly: choose metal AM to consolidate multi-part assemblies into a single component with no weld inspection, no leak paths and often less weight.
Look at functional parts, short runs or spare parts on demand for use-case guidance, or send the STEP + PDF drawing for a review.
FAQ
Metal 3D printing FAQ
SLM (Selective Laser Melting) and DMLS (Direct Metal Laser Sintering) are the same core process from different vendors. Both use a high-power laser to fully melt metal powder layer by layer in an inert-gas chamber. DMLS is the trademark used by EOS; SLM is the more general term. Some vendors use DMLS to imply partial sintering, but in practice modern industrial machines from EOS, SLM Solutions, Renishaw and Trumpf all fully melt the powder. Mechanical properties after heat treatment are equivalent.
Get a metal 3D printing quote in 24 hours
Send us a STEP + PDF drawing with tolerances and the alloy or standard you need. We review DFAM, propose the right process route and confirm price and lead time.