When to pick this combination
Hastelloy X is the default when service temperature crosses Inconel 718's 650 °C ceiling. It runs comfortably to 900 °C in oxidising service and is the dominant alloy for printed combustor liners and afterburner hardware.
- Service 650–900 °C
- Combustor and exhaust hardware
- Cyclic thermal duty without HIP+aging penalty
- Replacement of wrought N06002 sheet fabrications
Typical defects and how the model accounts for them
Hot cracking at thin-wall to bulk transitions is the dominant defect. ForgeCast flags any abrupt thickness jump > 3× as a cracking-risk feature and recommends fillet radii ≥ 1 mm to redistribute solidification stress.
Required post-processing
The allowables above assume the full post-processing chain. Skipping any step degrades the row by 15–35 %.
- Stress relief: 900 °C / 2 h / Ar
- EDM from plate
- Solution: 1175 °C / 1 h / water quench
- HIP: 1175 °C / 100 MPa / 4 h (optional for fatigue-critical)
- Machine sealing surfaces
- No precipitation age — solid-solution strengthening only
Suggested build parameters
Starting recipe; tune against first-article inspection on geometry-sensitive features.
- Layer: 40 μm
- Laser: 270 W
- Scan: 1000 mm/s
- Hatch: 100 μm
- Build plate: 100 °C
Frequently asked questions
Why no precipitation age?
Hastelloy X derives strength from solid-solution Mo/Cr/W, not γ′ or γ″ precipitates. Aging it would actually embrittle the alloy through carbide precipitation at grain boundaries.
Sources
- AMS 5754 — Hastelloy X sheet, strip, plate
- Haynes International Hastelloy X technical brochure