Stamping lamination price

The most critical factor is the material grade, typically Silicon Steel (Electrical Steel). You must specify the lamination thickness (commonly 0.2mm, 0.35mm, or 0.5mm), as thinner sheets reduce eddy current losses but increase cost. Additionally, verify the stacking factor, dimensional tolerances (typically within ±0.02mm for high-precision motors), and the burr height, which should ideally be under 0.02mm to prevent short circuits between layers.

Laminations require insulation coatings to prevent energy loss. C5 coating is standard for improved punchability and heat resistance, while C6 coating offers enhanced insulation for large machines. For high-end applications, self-bonding (back-lack) technology is used to eliminate the need for welding or riveting, which improves magnetic flux but carries a significant price premium due to specialized processing.

The choice between progressive die stamping and single-slot punching is the main cost driver. Progressive dies are ideal for high-volume production (100k+ units) as they offer the lowest unit cost despite high initial tooling investment. For prototypes or low volumes, laser cutting or single-slot punching is more economically feasible as it avoids expensive mold costs.

Suppliers should adhere to IEC 60404 for magnetic materials and ISO 9001 for quality management. For automotive applications (EV motors), IATF 16949 certification is mandatory. Ensure the supplier provides a Material Mill Test Certificate (MTC) to verify the silicon content and core loss properties (W/kg) meet your design requirements.

Silicon steel prices are volatile. It is recommended to sign a long-term framework agreement with the supplier or use a price formula linked to a public steel index. On Made-in-China.com, you can find 'Diamond Members' who often have more stable supply chains and can offer price validity periods of 15-30 days to protect your budget.

The primary risks are oxidation (rust) and physical deformation. Ensure the contract specifies VCI (Volatile Corrosion Inhibitor) packaging and vacuum sealing. Because these products are extremely heavy, use fumigated wooden crates with reinforced steel strapping. Always request Sea Freight Insurance to cover potential damage during transit.

Clearly define that the mold ownership belongs to the buyer once the tooling fee is paid. Negotiate a guaranteed mold life (e.g., 1 million strokes) and ensure the supplier provides free routine maintenance. Requesting a mold trial report (T1-T3) and physical samples before final approval is a standard industry safeguard.

For custom stamping, use a 30% deposit / 70% balance against BL structure. For the initial tooling, consider using Escrow services or Trade Assurance through reputable platforms like Made-in-China.com to ensure the funds are only released after the initial sample inspection (FAI) is approved.