When to pick this combination
EBM CoCrMo is the orthopedic-implant default because the hot build chamber yields a near-wrought lamellar microstructure with low residual stress and supports the trabecular surface lattices that drive osseointegration. Pick this when implant biocompatibility (ASTM F75) and surface-lattice fidelity dominate the requirement set.
- Acetabular cups with trabecular surfaces
- Femoral stems with osseointegration zones
- Patient-specific reconstruction implants
- Dental frameworks
Typical defects and how the model accounts for them
Surface roughness from the powder cake is high (Ra 25–40 μm) and is functionally desirable in the bone-interface zone. Articulating surfaces must be machined and polished separately. Sub-surface porosity is well-controlled by HIP.
Required post-processing
The allowables above assume the full post-processing chain. Skipping any step degrades the row by 15–35 %.
- Cake removal and bead-blast
- HIP: 1200 °C / 100 MPa / 4 h
- Solution anneal: 1220 °C / 1 h / Ar
- Machine articulating surfaces to mirror finish
- Passivate per ASTM F86
Suggested build parameters
Starting recipe; tune against first-article inspection on geometry-sensitive features.
- Layer: 70 μm
- Beam: 3000 W
- Chamber: 730 °C
- Scan: hatch + contour
Frequently asked questions
Does ForgeCast handle the F75 chemistry constraints?
Yes — the wizard pins the C content range (0.20–0.30 wt%) and warns if a supplier-provided lot chemistry drifts outside the F75 envelope.
Sources
- ASTM F75 — Cobalt-28 Chromium-6 Molybdenum Alloy Castings for Surgical Implants
- ASTM F3001 — Standard Specification for AM Ti-6Al-4V ELI
- ASTM F86 — Surface Preparation and Marking of Metallic Surgical Implants