Duraloy Super 22H is Duraloy Technologies' enhanced proprietary variant of its 22H cast heat-resisting alloy, built on the same 28% chromium - 50% nickel - tungsten cast matrix (DIN 2.4879 family, G-NiCr28W) with an approximate 2% cobalt addition. Duraloy markets Super 22H as a worldwide industry-standard heat-resisting casting alloy, used for demanding applications such as skid rider castings in steel mill reheat furnaces and radiant tubes that see continuous service in the 950-1250 degC (1740-2280 degF) range.

The cobalt addition is documented by third-party welding-consumable suppliers matching this alloy family as the specific distinction between standard 22H and Super 22H; it is understood in the industry to improve high-temperature strength and carburization/creep resistance versus the base 22H composition, though Duraloy's exact proprietary specification and quantified property gains are not published.

Like standard 22H, Super 22H is a cast product, not wrought bar or plate. It solidifies with a carbide-rich austenitic matrix that gives it hot strength and abrasion resistance in furnace and kiln service, at the cost of being noticeably more abrasive to machine than a comparable wrought nickel alloy.

Duraloy Super 22H machines much like standard 22H, with the same cast-alloy considerations dominating over pure alloy chemistry. The as-cast surface skin and the dense chromium-carbide network running through the matrix are highly abrasive to cutting edges, driving flank wear independent of the thermal effects seen in wrought nickel alloys. The small cobalt addition that distinguishes Super 22H from standard 22H raises high-temperature strength slightly further, which in practice means marginally more resistance to plastic deformation of the workpiece surface under cutting forces - a small additional demand on edge sharpness and rigidity rather than a change in the fundamental approach.

Low thermal conductivity concentrates heat at the cutting edge, and the austenitic matrix work-hardens readily under light or interrupted cuts, so a steady chip load that cuts beneath any hardened layer is essential. Castings frequently present interrupted, irregular surfaces from parting lines and riser remnants, which subjects the tool to impact loading in addition to steady wear and favors tougher carbide substrates over the most wear-optimized but brittle grades.

As with standard 22H, plan to machine below the as-cast skin, use rigid and vibration-damped setups, favor tough coated-carbide grades able to withstand interrupted engagement, keep speeds at the low end of the nickel-alloy range, and maintain adequate feed to avoid dwelling in the work-hardened surface layer.