331 is a heat-resisting austenitic alloy in the same Ni-Cr-Si family as 330, carrying even higher nickel and chromium content — roughly 41% nickel and 20% chromium, plus silicon and a small molybdenum addition — for further improved resistance to scaling, carburization, and thermal-cycling fatigue in demanding furnace-atmosphere service. Where 330 is already a step up from a standard 18-8 stainless in high-temperature capability, 331 pushes the nickel and chromium content higher still, which generally translates to better resistance to hot corrosion and metal-dusting attack in aggressive carburizing or sulfidizing furnace atmospheres, at the cost of even lower machinability and higher material cost.

Carbon in this family is intentionally elevated compared with a general-purpose wrought stainless — a deliberate feature of heat-resisting Ni-Cr-Si alloys used in cast or heavily-loaded fixture form, where carbide-network strengthening improves creep and high-temperature strength rather than being a defect to minimize. A specific, universally-published DIN/EN/Wnr cross-reference for the 331 designation was not found in general steel-standards literature — it appears to be used as a specialty or foundry-type designation within the 330 alloy family rather than a number carried across every international standard. Confirm the exact standard equivalent and composition against mill or foundry certification for critical applications.

No widely published international standard cross-reference was found for this designation. Composition is consistent with a high-alloy, high-carbon heat-resisting Ni-Cr-Si casting/fixture alloy in the 330 family — confirm against mill or foundry certification for critical applications.

331 machines like a demanding high-nickel heat-resisting alloy — at over 40% nickel it sits closer to a nickel-based superalloy than to any stainless steel in cutting behavior. Expect pronounced work hardening under any rubbing or dwelling at the cutting edge, low thermal conductivity that concentrates heat at the tool tip, and gummy, adhesive chip behavior that promotes built-up edge. The elevated silicon, molybdenum, and carbon content add abrasive wear on top of that adhesive tendency, so tool wear tends to be aggressive on both fronts at once.

Treat 331 with the same fundamentals used on nickel superalloys: sharp, positive-rake carbide with a tough substrate, decisive feeds that shear cleanly rather than rub, rigid setups to minimize deflection and chatter, and generous coolant to manage heat and built-up edge. Light finishing passes and dwelling cuts should be avoided, since both burnish rather than cut the surface and lock in a harder skin for the next pass to fight through. Expect cutting speeds well below general stainless steel, shorter tool life, and higher cutting forces than any of the lower-alloy grades in this family.

Values assume favorable cutting conditions: a well-matched insert grade, rigid tool and workpiece clamping, good-quality raw material, short tool overhang. This high-nickel heat-resisting alloy runs well below general stainless steel speeds.

Turning

Parting / Grooving

Milling