316L SS High Corrosion Fasteners

316L Stainless Steel Fasteners — High Corrosion Resistance | M3–M64 | Marine & Chemical Grade

316L (UNS S31603) stainless steel fasteners provide superior corrosion resistance compared to standard 304 stainless, particularly in chloride-rich environments such as marine, coastal, and chemical processing applications. The low-carbon (L) designation ensures optimal weldability and resistance to intergranular corrosion after welding or sensitization.

Material & Specifications

Size Range	M3 to M64 / #4 to 2-1/2″
Standard	ASTM F593 (bolts/screws), ASTM F594 (nuts), DIN/ISO dimensional standards
Material	316L (UNS S31603) — Low Carbon Austenitic Stainless Steel
Surface / Coating	Passivated (standard), PTFE coated (anti-galling option)
Tensile Strength	≥ 620 MPa (90 ksi) — ASTM F593 Group 2
Yield Strength	≥ 450 MPa (65 ksi)

Surface Treatment & Zinc Coating Quality

At BoltNutsPlus, we understand that surface treatment is critical to fastener longevity and performance. Our products undergo rigorous coating processes to ensure maximum corrosion resistance and durability. We offer five premium coating options, each tested to international standards:

• Hot-Dip Galvanizing (HDG) — Thick zinc layer (50-120μm) providing superior long-term corrosion protection for outdoor, marine, and industrial environments. Compliant with ISO 1461 / ASTM A153 standards. Salt spray resistance: 500-1,000+ hours. Ideal for structural steel assemblies exposed to harsh weather.
• Electroplated Zinc Blue-White (Zn Blue/White) — Bright, clean silver-blue appearance with 5-15μm zinc layer. Cr3+ passivation technology, fully RoHS compliant. Ideal for indoor machinery, electronics, and general-purpose applications requiring aesthetic appeal and moderate corrosion resistance.
• Color Zinc / Yellow Zinc (Iridescent Passivation) — Multi-colored iridescent passivation film offering enhanced corrosion resistance (100-200 hours salt spray) with a distinctive golden finish. Widely preferred in automotive, agricultural equipment, and construction machinery sectors for its balanced protection and visual appeal.
• Dacromet Coating — Advanced water-based zinc-chromium coating technology with NO hydrogen embrittlement risk. Provides 1,000+ hours salt spray resistance, making it the preferred choice for high-strength fasteners in extreme environments. Environmentally friendly (no heavy metal discharge), RoHS/ELV compliant, ideal for automotive and wind energy applications.
• Multi-Element Alloy Co-Permeation — Zinc-aluminum-rare earth alloy layer offering 2-3x the corrosion resistance of traditional galvanizing. Features self-healing properties at scratch points, ensuring long-term protection even in damaged areas. Ideal for critical infrastructure, power transmission towers, coastal projects, and marine installations.

Key Features

• 316L grade provides superior pitting corrosion resistance vs. 304 SS (PREN > 24)
• Low carbon content (<0.03%) prevents intergranular corrosion after welding
• Excellent resistance to chlorides, acids, and marine atmospheres
• Non-magnetic austenitic structure ideal for food and pharmaceutical applications
• PTFE coating option prevents galling during installation and removal
• Full ASTM F593/F594 certification with chemistry and mechanical test reports

Applications

• Marine and offshore platform fasteners (saltwater exposure)
• Chemical processing plant equipment and piping
• Food & beverage and pharmaceutical sanitary equipment
• Coastal and tropical infrastructure (bridge, railing, architectural)
• Swimming pool and water treatment equipment
• Any application requiring superior chloride corrosion resistance

Why Choose BoltNutsPlus?

• ISO 9001:2015 Certified Manufacturing — consistent quality you can trust on every batch
• 15+ Years of Export Experience — serving 40+ countries across 6 continents
• Full Traceability — material certificates (EN 10204 3.1) and comprehensive test reports included
• Custom Packaging & OEM/ODM — your brand identity, your specifications, our precision manufacturing
• Third-Party SGS / Bureau Veritas Inspection Available upon request
• 24-Hour Quote Response — same-day reply for urgent requirements; standard 24-hour turnaround