17Cr-4Ni Duplex Stainless

metal

17Cr-4Ni is a martensitic stainless steel characterized by moderate chromium content (17%), elevated cobalt (~8.5%), and significant silicon (~3.6%), which together promote high strength and hardness through precipitation hardening and martensitic transformation. This alloy is primarily used in demanding aerospace, defense, and tooling applications where high strength combined with corrosion resistance is required, and its cobalt addition distinguishes it from standard martensitic stainless steels by enhancing strength and thermal stability. The material competes with 17-4 PH and 15-5 PH variants in applications requiring a balance of machinability, strength, and environmental durability without the full cost of superalloys.

aerospace fasteners and structural componentsprecision tooling and dieshigh-strength corrosion-resistant springsdefense/military applicationspressure vessels and containmentpump and compressor components

Compliance & Regulations

?Conflict Free?RoHS?REACH?TSCA?Prop 65
Units:
siimperial
PropertyValueUnitConditionsSource
Elongation at Break(εf)
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-——
Ultimate Tensile Strength(σUTS)
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ksi——
Yield Strength (0.2% offset)(σy)
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ksi——
Verified Unverified Low confidence (<80%) Link to source

Regulatory Screening

Environmental

Quality & Standards

Industry-Specific

RoHS, REACH, and Prop 65 statuses are validated against official substance lists (ECHA SVHC Candidate List, OEHHA Prop 65, RoHS Annex II). Other regulations are estimated from composition and material classification. All screening is a starting point for due diligence — always verify with your supplier before making compliance decisions.