Magni Series Coating for Fasteners: What It Is and Why It Matters

What Is Magni Series Coating?

Magni coating is a high-performance, water-based zinc-aluminum flake coating system engineered for superior corrosion protection on metal fasteners and components. Developed by Magni International, the Magni series has become a benchmark surface treatment in the automotive, construction, and industrial fastener industries worldwide.

Unlike traditional electroplated zinc coatings, Magni uses a multi-layer system: a zinc-aluminum-rich basecoat provides cathodic corrosion protection to the substrate (steel, iron, aluminum), while a topcoat containing lubricating agents, pigments, and polymer resins delivers additional benefits including lubrication, acid and alkali resistance, and a clean, uniform appearance.

How Magni Coating Works

The Magni anticorrosion system is applied in two functional layers:

• Basecoat: A zinc and aluminum-rich layer that bonds to the metal substrate and provides cathodic protection — sacrificing itself to protect the base metal from rust and oxidation.
• Topcoat: Formulated with lubricating ingredients, pigments, and polymer resin to provide consistent torque-tension performance, chemical resistance, and aesthetic finish.

This dual-layer architecture allows Magni-coated fasteners to achieve 1,000+ hours of salt spray resistance (per ISO 9227 / ASTM B117) in a coating thickness of just 8–12 µm — far outperforming standard zinc electroplating at equivalent thickness.

Key Advantages of Magni Coatings on Fasteners

• Exceptional corrosion resistance: 720–1,500+ hours neutral salt spray (NSS) depending on the specific Magni grade and substrate.
• No hydrogen embrittlement risk: The water-based, non-electrolytic process eliminates the hydrogen embrittlement risk associated with electroplating — critical for high-strength bolts (Grade 10.9, 12.9).
• Consistent torque-tension control: Integrated lubricants ensure repeatable clamp force during assembly, reducing the risk of under- or over-tightening.
• RoHS & ELV compliant: Magni coatings are free of hexavalent chromium (Cr6+), cadmium, and other restricted substances — fully compliant with EU RoHS and ELV directives.
• Thin, uniform film: Typical coating thickness of 8–15 µm preserves thread tolerances on precision fasteners.
• Excellent chemical resistance: Resistant to acids, alkalis, fuels, and brake fluids — suitable for demanding under-hood and chassis environments.

Magni Series Grades: OEM Specifications

Different Magni grades are qualified to specific OEM standards. The table below summarizes the most common automotive OEM approvals:

Beyond automotive, Magni coatings are also widely specified in wind energy, heavy machinery, rail, and construction fastener applications.

Magni vs. Traditional Zinc Plating: A Quick Comparison

Which Fasteners Are Suitable for Magni Coating?

Magni coatings are compatible with a wide range of fastener types and standards, including:

• Hex bolts and socket head cap screws (DIN 931, DIN 912, ISO 4762)
• Flange bolts and wheel bolts
• Studs, nuts, and washers
• Self-drilling and self-tapping screws
• High-strength structural bolts (Grade 8.8, 10.9, 12.9)

The process is particularly recommended for high-strength fasteners where hydrogen embrittlement from electroplating is a concern.

Fullerkreg Fasteners & Magni Coating

At Fullerkreg Fasteners, we supply DIN/ISO standard fasteners with Magni series surface treatment to meet the exacting requirements of automotive OEMs, Tier 1 suppliers, and industrial customers worldwide. Whether you need Magni 565 for GM/BMW specifications or Magni 515 for Ford-qualified applications, our team can advise on the right grade, substrate, and thread tolerance for your project.

Contact us for bulk pricing, technical datasheets, and sample requests.