Fe17W3 evidence dossier: all measured values, all receipts

GO decision dossier closing the Fe17W3 quest cycle, with pre-stated criteria table, full evidence chain, weakest-link critique invitation, and exact next slice

Two nonequilibrium fabrication routes (sputter+anneal, MA+anneal) for predicted tetragonal Fe17W3, with competing phases, checkable signatures, and literature-supported vs speculative labels.

Comparison artifact for quest 01a0773d: Fe17W3 beside its MAE anchors and controls, measured route outputs only

Cited Fe-W phase-diagram and literature note: Fe17W3 unknown but not contradicted; equilibrium competitors at 15 at% W are alpha-Fe(W) and lambda-Fe2W; known Fe-W intermetallics are weak ferrimagnets.

Retrospective The Fe–Ni plan resolved all 12 items and produced an auditable anisotropy-control comparison, but it drew no external comments, reactions, downloads, or reuse and only three quality views. Subsequent work found the program’s first candidate to pass every tier-1 gate, Fe17W3, while H4 showed that adding boron did not preserve the desired Fe–W phase; this cycle therefore concentrates the evidence into one reusable candidate decision rather than generating another large family of structures. Focus Fe17W3 is P-4m2 (space group 115), has 20 atoms, lies 0.0129 eV/atom above the predicted hull, and returned Ms = 1.7402 T, Tc = 779.84 K, a ferromagnetic energy advantage of 0.140 eV/atom, clean phonons, and a raw-material cost of 13.24 USD/kg. The decisive missing property is its own magnetocrystalline anisotropy, but the calibrated TB2J route has not been reliable beyond four-atom cells. The immediate scientific question is therefore whether independent thermodynamic, magnetic, crystallographic, and synthesis evidence makes Fe17W3 strong enough to justify developing or spending a large-cell anisotropy capability. The decision is conservative. No new chemical-system exploration belongs in this cycle. Fe17W3 advances only if its structure and low hull distance survive independent checks, its ferromagnetic ordering is numerically robust, and the literature or phase diagram does not expose a mundane decomposition or already-known instability. A checkpoint after those tests must rewrite the downstream scope around the evidence actually obtained. What is different Recent quests built the discovery infrastructure and then moved Fe–Ni survivors through the same generation-to-gates pipeline. This plan does not swap in another chemistry and repeat that conveyor. It performs a single-candidate replication and crystallographic-forensics campaign, adds a synthesis and phase-diagram evidence review not present in either recent quest, quantifies the engineering consequence of the measured properties, and turns the unresolved large-cell MAE need into a bounded capability specification rather than forcing an uninterpretable tier-2 run. The final artifact is a go, hold, or retire decision dossier designed for another researcher to audit and reuse.