CoFeK₂P₂

Architectural potential

A cobalt-iron-potassium phosphide sintered at 1100 °C — the most neutral-toned of the powder-pressed metals in this batch and the one closest to a general-purpose hardware body. Two hundred and fifty megapascals of compression is a step below the zirconium variant but still in the cast-iron register, and the fifty-three-per-cent CO₂ cut against structural steel remains intact. Place it where the hardware needs to disappear into the detail rather than announce itself: structural brackets in painted finishes, furniture cleats and shelf brackets, door-frame anchors, stair-stringer clips, balustrade posts in utilitarian fit-out. The neutral colour makes it a drop-in substitute for cast-iron hardware in heritage retrofits where the visual register has to match existing ironwork. Cost at €7.06 per 200 g batch sits mid-range for the family, with a 500 g workshop ceiling that keeps production in the per-piece register — a single stair detail or one set of connector clips rather than a façade run. The caveat is the two-hundred-and-fifty-megapascal figure itself: adequate for secondary structural hardware and robust for most non-seismic fittings, but below the threshold where it could replace hot-rolled steel in primary frames, so first-use projects should keep it in brackets, clips and nodes rather than primary members.

Material character

The slab reads an even cool grey with a barely perceptible warm cast from the iron content — unmistakably the neutral powder-pressed register rather than anything copper-toned. At 2.86 g/cm³ over 85×85×48 mm the piece lifts single-handed with a firm two-finger grip, closer in weight-feel to aluminium billet than to the phosphide-heavy zirconium sibling. Surface matte with the regular fine grain of a sintered pressing; edges as-pressed, squared but not razor-sharp. Rings cleanly but short under a tap — the acoustic signature of a dense powder-consolidated body rather than a solid cast. A step lighter and duller-toned than the copper-bearing sinters in the same family.