Uranus B28 is Aperam/Industeel's trade name for the high-nickel superaustenitic alloy widely known as Alloy 28 or Sanicro 28, UNS N08028, EN 1.4563. It's the highest-nickel grade in FM Carbide's Uranus lineup, running roughly 27% chromium and 30-34% nickel with a moderate 3-4% molybdenum addition and 0.6-1.4% copper — a very different alloying strategy from the 6-Mo superaustenitic grades (Uranus B25/B26) also carried on this site.

Where B25 and B26 lean on high molybdenum and nitrogen to maximize PREN (pitting resistance equivalent) against chloride attack, Uranus B28's high nickel and copper content is aimed at a different threat entirely: resistance to hot, concentrated sulfuric and phosphoric acid, plus stress-corrosion cracking resistance that the 6-Mo grades don't specifically target. Its PREN, by the standard chloride-pitting formula, runs lower than the 6-Mo grades — that's expected, because chloride pitting isn't the corrosion mode B28 was designed to solve. Typical applications include sulfuric and phosphoric acid production and handling equipment, pickling lines, and nuclear fuel reprocessing hardware.

Uranus B28 carries the highest nickel content of any alloy in FM Carbide's Uranus lineup, and that shows up directly in how it cuts: it is the gummiest, most work-hardening-prone grade of the group. Fully austenitic with no ferrite phase to speak of, the very high nickel fraction keeps the matrix soft and extremely ductile — which means the material wants to smear and drag under the tool rather than shear cleanly, and any hesitation or rubbing at the edge produces a hardened skin almost immediately.

Sharp, positive-rake inserts with an aggressive stainless-rated chipbreaker are non-negotiable on this alloy; a dull or worn edge degrades tool life far faster here than on 316 or even the 6-Mo superaustenitic grades. Feed rates need to stay firm to keep the edge biting rather than rubbing, and coolant delivery is critical given the alloy's low thermal conductivity. Machine and workholding rigidity matter as much here as on any material on this site — deflection or chatter on Uranus B28 shows up immediately as work-hardened surface that ruins the next pass.