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Stellite 6 vs 12 vs 21

Selecting cobalt-based hardfacing for wear, impact, galling, cavitation and elevated temperature.

Stellite 6 — balanced general purpose

A widely used cobalt alloy with a useful balance of wear, galling, corrosion, cavitation and moderate-impact resistance.

Stellite 12 — wear-focused

Higher carbide content provides greater abrasive/sliding wear resistance than Stellite 6, with a trade-off in impact tolerance and machinability.

Stellite 21 — toughness-oriented

A lower-carbide, tougher matrix makes it relevant where impact, cavitation and crack resistance matter more than maximum hardness.

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