Stainless Steel Self-clinching Fastener Passivation & Rust Prevention Specification, Salt Spray Anti-rust Selection Guide For Sheet Metal Clinch Parts

Stainless Steel Self-clinching Fastener Passivation & Rust Prevention Specification, Salt Spray Anti-rust Selection Guide For Sheet Metal Clinch Parts

Stainless steel clinch fasteners are not completely rust-proof. Cold working processes including heading, thread rolling and cold pressing destroy the original surface passivation film, causing lattice disorder and residual iron ions. In humid and coastal environments, clinch positions generate pitting flash rust. Most sheet metal factories misjudge it as inferior material, while the real cause is unqualified surface treatment. Standardized passivation is the core procedure to eliminate clinch part rusting.

1. Anti-rust Performance Comparison Of Three Clinch Part Surface Treatments

2. Scenario-based Selection Rule For SUS304 & SUS316 Clinch Parts

1. SUS304 standard passivation clinch parts: Suitable for dry inland areas, indoor energy storage and regular industrial sheet metal; 2. SUS304 enhanced sealing passivation: For riverside, lakeside and slightly humid outdoor equipment; 3. SUS316 standard passivation: For coastal mild salt spray equipment with better corrosion resistance than 304; 4. SUS316 enhanced passivation: Dedicated for coastline communication cabinets and high-corrosion working conditions.

3. Troubleshooting & Solutions For Clinch Part Rusting

1. Short-term flash rust on new parts: Residual cold-work iron debris without passivation, re-passivation solves the problem; 2. Local rust after clinching: Pressing destroys partial passivation film, spray stainless steel anti-rust agent for sealing; 3. Batch salt spray failure: Failed passivation solution or insufficient treatment time, adopt enhanced passivation process; 4. Diffused rust at splicing position: Galvanic corrosion of dissimilar metals, use same-material clinch parts plus insulation isolation.