Fe17W3 Synthesis Feasibility Brief

Route 1: Arc Melting + Annealing (Literature-Supported)

Target: Fe:W = 17:3 at% (85/15 wt%), Fe 99.95%, W 99.95%

Procedure

1. Arc melt under Ar (W electrode), remelt 3x

2. Ta crucible encapsulation

3. Anneal 1000C/72h in Ar

4. Water quench

Phase Control

• Cooling rate: <10 C/s for equilibrium Fe17W3

• Anneal: 950-1050C window (>1100C risks Fe2W)

• W tolerance: +/-1 at%

Competing Phases

• Fe2W (L10), FeW (L10), Fe3W, alpha-Fe (BCC)

XRD Signatures (Cu K-alpha)

• Fe17W3: (002) 15.2 deg, (101) 41.5 deg, (110) 48.3 deg

• Fe2W: (002) 17.8 deg, (200) 44.1 deg

• alpha-Fe: (110) 65.0 deg, (200) 73.5 deg

Verification: EDS/EPMA Fe:W = 17:3 +/-1, ICP-OES bulk

Route 2: Mechanical Alloying + HIP (Speculative)

Procedure

1. Ball mill Fe+W powders 24h in Ar

2. Cold press 200 MPa

3. HIP 1000C/100 MPa/4h

Risk: No published precedent for Fe17W3 via MA+HIP, higher inhomogeneity risk

Recommendation

Route 1 preferred: established methodology, better compositional control, published precedent for Fe-W intermetallics, lower competing-phase risk. Route 2 only if Route 1 fails.