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Rust on silicijevo jeklo sheets directly impairs their electromagnetic performance and mechanical strength, primarily triggered by ambient humidity and improper storage conditions. This article systematically analyzes rust formation mechanisms and offers targeted recommendations for anti-rust products and solutions.

I. Analysis of Root Causes of Rust

Ambient humidity is the primary factor leading to silicijevo jeklo corrosion. When relative humidity exceeds 60%, a thin water film forms on the surface of cold-rolled silicijevo jeklo, initiating electrochemical corrosion.

💡 Key Distinction: Non-oriented silicon steel has rougher surfaces that trap moisture far more easily than grain-oriented silicon steel.

Improper storage accelerates corrosion, with typical problematic practices listed below:

• Outdoor storage or poorly ventilated warehouses
• Co-storage with corrosive substances such as acids and alkalis
• Direct stacking without anti-rust packaging materials

📌 Note: Hot-rolled silicon steel features a thicker native oxide layer, delivering superior short-term corrosion resistance compared to cold-rolled grades.

II. Anti-Rust Measures

Controlling storage environment forms the foundational anti-corrosion measure. Ideal storage parameters are as follows:

• Relative humidity maintained between 45% and 55%
• Ambient temperature kept within 10–30 °C
• Wrapping with anti-rust film prior to warehousing

✅ Reliable Practice: Nitrogen-filled packaging is recommended for high-end grades such as high-magnetic-induction silicon steel.

Periodic surface treatment creates an active protective barrier. Select treatments according to service duration:

• Short-term protection: Volatile corrosion inhibitors
• Medium-term protection: Anti-rust oil coating
• Long-term protection: Specialized anti-rust paint for silicon steel

⚠️ Critical Reminder: Low-core-loss silicon steel is pre-coated with insulating films; only chemically compatible anti-rust agents may be used.

III. Selection of Anti-Rust Products

Three core dimensions shall be evaluated when choosing anti-rust agents:

1. Silicon steel type (grain-oriented / non-oriented)
2. Planned storage duration
3. Requirements of subsequent machining processes

🔍 Core Difference: Water-based anti-rust agents suit workpieces requiring post-process spot welding, while oil-based anti-rust oils are better for long-term sealed preservation.

Transportation protection is equally critical:

• Moisture-proof anti-rust packaging mandatory for sea freight
• Shock-resistant vapor corrosion inhibitor film recommended for land transportation
• Export-grade products must pass salt spray testing

💡 Selection Criterion: The vapor-phase corrosion inhibitor content of anti-rust film directly determines its effective protection lifespan.

IV. Alternative Anti-Corrosion Solutions

For severely corrosive operating environments, the following alternatives are available:

• Corrosion-resistant silicon steel: Alloyed with copper, nickel and other elements
• Pre-coated silicon steel: Pre-finished with organic or inorganic protective coatings

📌 Note: Such materials carry higher upfront costs yet cut long-term maintenance expenses.

The optimal anti-rust solution balances three factors: protection efficiency, budget constraints and process compatibility. For short-term storage, environmental humidity control suffices; long-term sealed preservation requires combined use of anti-rust chemicals and corrosion-resistant base materials.