Freemelt ONE

The Freemelt ONE is an EBM 3D printer from Freemelt with a 100 x 100 x 100 mm build volume.

Specifications

Electron Gun: Diode electron gun with laser-heated cathode; 0–6 kW power; 30–60 kV acceleration voltage.

Scanner: Electromagnetic deflection coils; scan speed up to 4 km/s; spot size adjustable from 1 to 100 (smallest to largest).

Build Volume: Cylindrical Ø100 × H100 mm: designed for small powder quantities (cups, not buckets).

Chamber/Vacuum: 70-litre vacuum chamber with high-capacity pumps; working pressure ≤ 1×10⁻⁴ hPa; fast pump-down cycle.

Process Format: Open Build File (OBF): fully open beam-path programming; no proprietary lock-in.

Layer Thickness: 50–200 µm; typical 80–100 µm for metals.

Calibration

Spot Size: Set focal distance for minimum spot in the melt plane: verify with electron imaging before production run.

Vacuum: Confirm ≤ 1×10⁻⁴ hPa before powder loading; check O-rings weekly under intensive use.

OBF Preheat Strategy: Optimise preheat scan pattern for new alloy using Freemelt-provided template OBF files.

Recoater Layer: Visual/optical check of each powder layer: the small volume means even a small amount of moist powder causes failure.

Common defects

Smoke Event: Insufficient preheating/charge buildup: rework OBF preheat, increase beam current.

LOF Porosity: Low energy density for new alloy: reduce scan speed, increase beam current.

Solidification Cracking: Add controlled soak in OBF after last layer.

Orange-peel / Unstable Surface: Check powder flowability and PSD; eliminate satellite fines.

What it is used for

Novel Alloys (Nb, W, TiAl, reactive metals): The only way to study these with full beam-path control.

DoE Parameter Development: Small powder quantities and fast cycles are ideal for Design of Experiments.

Academic Training: OBF lets students program EB-PBF from scratch.

Pre-production Parameterisation for eMELT-iM: Developed parameters transfer directly.