Stellite 100 is a Deloro-developed cobalt-chromium-tungsten-carbon alloy positioned at the top of the standard Stellite hardness range. Where most Stellite grades are chosen for general wear, corrosion, or galling resistance, Stellite 100 was historically marketed specifically for metal-cutting-tool and extreme-abrasion applications (per its original 1968 ASM Alloy Digest listing, filed under Deloro Stellite Ltd) - it maintains a working edge and resists softening at elevated temperature better than most of its siblings in the family.

It is no longer carried in Kennametal Stellite's current standard alloy catalog, which most current Stellite grades (1, 6, 12, 19, 21, and others) still are, so up-to-date manufacturer composition sheets are not publicly available. This page reflects FM Carbide's existing reference record for the alloy pending independent re-confirmation against a current datasheet.

Stellite 100 is, by its own design brief, the hardest and most abrasion-resistant grade in the standard Stellite lineup - a property that is directly at odds with being easy to machine. Its very high carbon and tungsten content produces an exceptionally dense network of primary carbides, and that carbide fraction is what dominates cutting behavior: the alloy behaves less like a metal being sheared and more like a bonded abrasive being ground away, regardless of the cutting tool material used.

Where the wear-resistant Stellite grades as a group are already more abrasive to cutting tools than the high-temperature structural cobalt alloys (S 816, Stellite 188) covered elsewhere in this library, Stellite 100 sits at the far end of that group - its carbide loading is at or above Stellite 1's, which is itself among the highest-carbon grades in the family. Expect tool life shorter than on any other alloy in this immediate Stellite group at comparable cutting parameters.

Because Stellite 100 was historically valued for holding a cutting edge under heat, it also resists the kind of edge-temperature softening that some machining strategies rely on to ease chip formation. Very conservative speeds, maximum rigidity, robust (not sharp/fragile) edge preparation, and abrasion-resistant carbide grades are essential; grinding is the standard finishing method for hardfaced or cast Stellite 100 surfaces rather than turning or milling to final size.