Standard: ZQ 4725 - 2006
Available sizes: M4 to M8 (4 sizes)
| Size | P | e | r | k_max | k_min | s_max | ds_max | ds_min | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| M4 | 0.8 | 4 | 3.5 | 8.5 | 8.28 | 16 | 5 | 4.58 | 2.5 |
| M5 | 1.25 | 6 | 5 | 13 | 12.73 | 22 | 8 | 6.86 | 4 |
| M6 | 1.75 |
| 10 |
| 7.5 |
| 18 |
| 17.73 |
| 30 |
| 12 |
| 11.43 |
| 6 |
| M8 | 2 | 14 | 10 | 24 | 23.67 | 38 | 16 | 16 | 8 |
Standard corrosion protection for indoor and mild outdoor environments.
Salt spray: 96–200 hours | RoHS compliant (trivalent chromium)
High-performance coating for automotive, marine, and harsh environments.
Salt spray: 720–1500 hours | Recommended for grade 8.8+
Heavy-duty protection for structural and outdoor applications.
Salt spray: 500–1000 hours | Thread tolerance adjustment required
Note for high-strength fasteners (Grade 10.9, 12.9): Electroplating processes require hydrogen embrittlement relief baking (minimum 4 hours at 200°C within 4 hours of plating). Contact our engineering team for grade-specific plating recommendations.
Request detailed technical specifications, material certifications, and availability information for your application requirements. Our engineering team can provide product recommendations, custom specifications, and technical documentation.
© 2026 Ningbo Ruixi Metal Surface Technology Co., Ltd.. All rights reserved.