Stellite 23 is a cobalt-chromium-tungsten wear-resistant alloy in the broader Stellite family, positioned as a moderate-carbide grade: a nickel and iron addition alongside chromium and tungsten give it more toughness than the highest-carbon numbered grades (such as Stellite 1, 3, or 20), while its carbide fraction is still well above that of a low-carbon, solid-solution cobalt superalloy like Stellite 25/L-605.

Transparency note: unlike Stellite 3, 20, 21, 25, and 31, which appear in Kennametal's current published Stellite alloy catalog with manufacturer-verified nominal compositions, Stellite 23 does not currently appear on Kennametal's official numbered-grade list. The composition figures below are the reference-grade values found consistently in independent machining-data references (including the prior version of this page), but no AMS, ASTM, or UNS designation could be confirmed for this specific grade, and no manufacturer datasheet was located to verify it against a certified specification. Treat these figures as general reference data rather than a mill-certified spec, and confirm against heat-specific certification for critical applications.

With chromium in the mid-20s percent and only moderate tungsten and carbon, Stellite 23 falls between the highly abrasion-resistant, high-carbide grades (Stellite 1/3/20) and the tougher, lower-carbide cast grades (Stellite 21/30/31) in this library, making it suited to wear applications where a balance of abrasion resistance and toughness is needed rather than maximum hardness alone.

Stellite 23's moderate carbon (0.4%) and tungsten (5%) content place it below the most carbide-dense Stellite grades in overall abrasiveness, but it still carries the core machining challenges common to every cobalt-base alloy: low thermal conductivity that concentrates cutting heat at the tool edge rather than the chip, retained hardness at elevated temperature with little thermal softening benefit at higher speeds, and a strong tendency to work-harden under light, rubbing, or inconsistent cuts.

Because this alloy is typically supplied and used in cast or hardfaced form rather than as homogeneous wrought bar, expect a carbide-bearing microstructure similar in character to other cast Stellite grades, with associated risk of localized flank-wear spikes when the tool encounters carbide-rich regions. Casting porosity and surface skin hardness (if hardfaced or as-cast) should also be accounted for on the first pass.

Sharp, ground carbide edges with adequate positive rake, rigid low-deflection setups, steady chip loads to avoid work hardening, and generous coolant flow are the standard countermeasures. Given the unverified certification status of this grade noted above, it is good practice to confirm actual hardness and carbide content on incoming material before committing to aggressive cutting parameters.