Stellite 45 is a cobalt-chromium-tungsten wear-resistant hardfacing alloy distinguished within the Stellite family by a meaningful nickel addition (roughly 10.5%) alongside its chromium and tungsten content. Most mainstream Stellite hardfacing grades (Stellite 1, 4, 6, 12) hold nickel to a residual, incidental level of 3% or less; a nickel content in the 10% range is unusual for this branch of the family and is more typical of the toughness-oriented, lower-carbon Stellite grades. Combined with a carbon content of around 0.3% - well below Stellite 6's ~1% - this points to Stellite 45 being formulated as a tougher, more ductile alternative within the wear-resistant cobalt-alloy lineup rather than a maximum-hardness abrasion grade.

Stellite 45 is a lesser-documented, specialty designation compared to the mainstream Stellite 1/4/6/12/21 series that Kennametal Stellite currently markets and publishes data sheets for. The composition below is drawn from the specialty machining reference database FM Carbide has used historically for this material; it has not been independently cross-verified against a current manufacturer data sheet, so hardness and tensile strength figures are omitted rather than estimated. If you are sourcing Stellite 45 for a specific application, confirm current composition and mechanical properties directly with your material supplier.

Like other cobalt-base wear alloys, Stellite 45's machinability is governed primarily by its hard carbide phase dispersed through a tough cobalt-chromium matrix, plus the alloy's poor thermal conductivity relative to steel. Heat generated at the cutting edge does not conduct away into the chip efficiently, so it concentrates at the tool-chip interface and accelerates crater wear and edge rounding. Its lower carbon content compared to Stellite 6 (0.3% versus roughly 1%) means a smaller volume fraction of hard carbides, which generally translates to somewhat better machinability and edge life than the higher-carbon Stellite grades, at the cost of a lower as-cast hardness and wear resistance in service.

As with all Stellite grades, the alloy work-hardens readily under cutting forces, so light, hesitant, or interrupted cuts create a hardened skin that is harder to machine than the parent material. Rigid setups, sharp positive geometries, hard PVD/CVD-coated carbide grades suited to superalloys, and consistent chip loads are the standard countermeasures. Geometries proven on austenitic stainless steel are a reasonable starting point, refined with the cobalt-superalloy-specific grades below.